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Divestitures (Details) - USD ($) $ in Millions		12 Months Ended
Divestitures (Details) - USD ($) $ in Millions	Sep. 29, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Oct. 31, 2025
Business Combination [Line Items]
Gain (Loss) on Disposition of Business		$ 0	$ 0	$ 129
Other Operating Segment \| Certain South Mansfield Upstream Interests
Business Combination [Line Items]
Disposal Group, Consideration					$ 398
Transmission, Power & Gulf [Member] \| Certain Gulf Coast Liquids Pipelines
Business Combination [Line Items]
Disposal Group, Consideration	$ 348
Gain (Loss) on Disposition of Business	$ 129

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Regulatory Assets and Liabilities

12 Months Ended

Dec. 31, 2025

Regulated Operations [Abstract]

Regulatory Assets and Liabilities [Table Text Block]

Note 10 – Regulatory Assets and Liabilities

The components of regulatory assets and liabilities include the effects of deferred taxes on equity funds used during construction, AROs, shipper imbalance activity, fuel and power cost differentials, depreciation, negative salvage, pension and other postretirement benefits, trackers, and rate allowances for deferred income taxes at historically higher federal and state income tax rates.

Williams


	December 31,
	2025		2024
	(Millions)
Current assets reported within Other current assets and deferred charges	$	130	$	84
Noncurrent assets reported within Regulatory assets, deferred charges, and other	568		582
Total regulatory assets	$	698	$	666


Current liabilities reported within Other current liabilities	$	117	$	85
Noncurrent liabilities reported within Regulatory liabilities, deferred income, and other	1,202		1,300
Total regulatory liabilities	$	1,319	$	1,385

Transco


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	70	$	47

ARO	51		16
Deferred cash out	—		6
ARO - Eminence	5		5
Total current regulatory assets	126		74
Long-term regulatory assets:
ARO	195		243
Grossed-up deferred taxes on equity AFUDC	28		29
ARO - Eminence	10		15
Slug catcher	6		6

Other	29		27
Total long-term regulatory assets	268		320
Total regulatory assets	$	394	$	394

Current regulatory liabilities:
Electric power cost	$	59	$	26
Deferred taxes - liability	18		31
Postretirement benefits other than pension	5		—
Pension	5		—
Deferred cash out	5		—
Other	1		1
Total current regulatory liabilities	93		58
Long-term regulatory liabilities:
Negative salvage	592		632
Deferred taxes - liability	246		252
Postretirement benefits other than pension	22		31
Pension	22		30
Sentinel meter station depreciation	7		7
Other	25		24
Total long-term regulatory liabilities	914		976
Total regulatory liabilities	$	1,007	$	1,034

The significant regulatory assets and liabilities include:

Fuel recovery: This amount represents the value of the cumulative volumetric difference between the gas retained from customers and the gas consumed in operations. These amounts are not included in the rate base, but they are expected to be recovered in subsequent annual fuel tracker filings.

ARO: This regulatory asset balance includes the uncollected ARO depreciation expense and accretion expense and amounts are not included in rate base. The regulatory asset is being recovered through rates, and is being

amortized to expense consistent with the amounts collected in rates (see AROs in Note 9 – Property, Plant, and Equipment).

ARO- Eminence: This regulatory asset balance is associated with the Eminence Storage Field retirement costs. The regulatory asset is being recovered through rates and is being amortized to expense consistent with the amounts collected in rates.

Grossed-up deferred taxes on equity AFUDC: This regulatory asset balance is established to offset the deferred tax for the equity component of the allowance for funds used during the construction of long-lived assets. Taxes on capitalized funds used during construction and the offsetting deferred income taxes are included in the rate base and are recovered over the depreciable lives of the long-lived assets to which they relate.

Slug catcher: This amount represents certain costs associated with the replacement of a component of a slug catcher which was included in the Docket No. RP24-1035 rate case settlement. A regulatory asset has been established to recognize the recovery of Transco’s investment in the slug catcher as it is collected through Transco’s depreciation rates and is being amortized at the prescribed depreciation rate for onshore transmission facilities.

Electric power cost: This amount represents the value of the difference between the electric power costs recovered from our customers and the electric power costs incurred in operations. These amounts are not included in the rate base, but they are expected to be recovered in subsequent annual electric power tracker filings.

Deferred taxes - liability: This amount represents the excess deferred income taxes (EDIT) created by the reduction in the federal corporate income tax rate under the Tax Cuts and Jobs Act of 2017 (TCJA), along with the impact of the weighted marginal state income tax rate. A regulatory liability has been recorded for these excess deferred taxes. The timing of the refund of the regulatory liability to rate payers is stated in the Docket No. RP24-1035 rate case settlement.

Postretirement benefits other than pension: Transco previously recovered the actuarially determined cost of postretirement benefits through rates that were set through periodic general rate filings. Any differences between the annual actuarially determined cost and the amounts recovered in rates were recorded as regulatory assets or liabilities to be collected or refunded through future rate adjustments. Effective with Transco’s Docket No. RP24-1035 rate case settlement, Transco will not recover any postretirement benefit costs incurred after February 28, 2025, and will no longer record a regulatory asset or liability. The postretirement benefits regulatory liability balance as of February 28, 2025, is currently being amortized over a six-year period (see Note 7 – Employee Benefit Plans).

Pension: Williams previously made annual cash contributions to the pension plans, based on actuarial estimates. Transco previously recovered the actuarially determined pension cash contributions through rates that were set through periodic general rate filings. Effective with Transco’s Docket No. RP24‑1035 rate case settlement, Transco will no longer recover pension cash contributions through rates or record related pension regulatory liabilities. The pension regulatory liability balance as of February 28, 2025, is currently being amortized over a six-year period (see Note 7 – Employee Benefit Plans).

Deferred cash out: This amount represents the deferral of gains or losses on the purchases and sales of gas imbalances with shippers. These assets and liabilities amounts will be recovered or refunded, respectively, under terms provided for in Transco’s FERC tariff.

Negative salvage: Transco’s rates include a component designed to recover certain future retirement costs for which it is not required to record an ARO. Transco records a regulatory liability representing the cumulative residual amount of recoveries through rates, net of expenditures associated with these retirement costs.

Sentinel meter station depreciation: This amount reflects the incremental depreciation being recorded related to the meter station modifications made for three of the Sentinel shippers. These modifications will be recovered through a surcharge over a defined period of time as stated in the Sentinel FERC order. The incremental

depreciation represents the difference between the FERC granted depreciation rate for such facilities in the last rate case as compared to the depreciation rates in the Sentinel order which are based on the contractual terms in the surcharge agreements. The incremental depreciation will be recorded through the end of the contractual term and then will be amortized.

NWP


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	—	$	4
Levelized depreciation	3		2
Total current regulatory assets	3		6
Long-term regulatory assets:
Levelized depreciation	5		7
Grossed-up deferred taxes on equity AFUDC	3		4
Washington State Carbon and Greenhouse Gas Tax	72		38
Total long-term regulatory assets	80		49
Total regulatory assets	$	83	$	55

Current regulatory liabilities:

Deferred taxes - liability	$	20	$	20

Fuel recovery	—		—
Total current regulatory liabilities	20		20
Long-term regulatory liabilities:
Deferred taxes - liability	146		160
Postretirement benefits other than pension	44		43
Negative salvage - net	35		30

Total long-term regulatory liabilities	225		233
Total regulatory liabilities	$	245	$	253

The significant regulatory assets and liabilities include:

Levelized depreciation: Levelized depreciation allows contract revenue streams to remain constant over the primary contract terms by recognizing lower than book depreciation in the early years and higher than book depreciation in later years. The depreciation component of the levelized incremental rates will equal the accumulated book depreciation by the end of the primary contract terms. The difference between levelized depreciation and straight-line book depreciation is recorded as a FERC approved regulatory asset or liability and is eliminated over the levelization period.

capitalized funds used during construction and the offsetting deferred income taxes are included in the rate base and are recovered over the depreciable lives of the long-lived assets to which they relate.

Washington State Carbon and Greenhouse Tax: This amount represents the cost of emission allowances and the associated accumulated interest as a result of the passage of the state of Washington Climate Commitment Act that took effect January 1, 2023. NWP’s Settlement allows it to recover the costs of purchasing allowances under the program in NWP’s next rate case.

Deferred taxes - liability: This amount represents the EDIT created by the reduction in the federal corporate income tax rate under TCJA, the decrease in the weighted marginal state income tax rate, and a state income tax adjustment associated with changes in ownership. The timing of the refund of the regulatory liability to rate payers is stated in the Docket No. RP22-1155 rate case settlement. Additionally, as of December 31, 2025, Northwest has $6 million of rate based deferred taxes established as a result of a decrease to the effective state income tax rate. This item will be subject to future discussions and negotiation with our customers in our next rate case.

Postretirement benefits other than pension: NWP seeks to recover the actuarially determined cost of postretirement benefits through rates that are set through periodic general rate filings. Any differences between the annual actuarially determined cost and amounts currently being recovered in rates are recorded as regulatory assets or liabilities and collected or refunded through future rate adjustments. These amounts are not included in the rate base, and NWP is not currently recovering postretirement benefit costs in its rates (see Note 7 – Employee Benefit Plans).

Negative salvage, net of ARO asset: This regulatory liability balance reflects the amount that NWP has recovered in rates related to future retirement costs offset by depreciation of the ARO asset and accretion expense of the ARO liability due to the passage of time. AROs are expected to be fully recovered through the net negative salvage component of depreciation included in rates (see AROs in Note 9 – Property, Plant, and Equipment).

Statement of Net Income - Transco - USD ($) $ in Millions	12 Months Ended
Statement of Net Income - Transco - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues [Abstract]
Revenues	$ 11,950	$ 10,503	$ 10,907
Costs and Expenses [Abstract]
Depreciation, depletion, and amortization	2,347	2,219	2,071
General and Administrative Expense	721	708	665
Other Operating Income (Expense), Net	(7)	(60)	(40)
Total costs and expenses	7,754	7,164	6,596
Operating income (loss)	4,196	3,339	4,311
Interest expense	(1,442)	(1,364)	(1,236)
Other Nonoperating Income (Expense)	69	108	99
Net income (loss)	3,625	2,986	4,405
Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	3,263	2,964	2,866
Costs and Expenses [Abstract]
Cost of natural gas sales	126	118	137
Utilities Operating Expense, Maintenance and Operations	509	510	517
Depreciation, depletion, and amortization	574	545	519
General and Administrative Expense	223	216	215
Taxes, Miscellaneous	114	111	105
Other Operating Income (Expense), Net	27	(35)	(38)
Total costs and expenses	1,573	1,465	1,455
Operating income (loss)	1,690	1,499	1,411
Interest expense	(332)	(324)	(324)
Interest Income, Other	37	58	87
Public Utilities, Allowance for Funds Used During Construction, Additions	35	88	77
Other Nonoperating Income (Expense)	(4)	(8)	(4)
Net income (loss)	1,426	1,313	1,247
Natural Gas, US Regulated \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	2,874	2,619	2,506
Natural Gas, Storage \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	228	200	186
Natural Gas, Gathering, Transportation, Marketing and Processing \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	126	118	137
Product and Service, Other \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenues [Abstract]
Revenues	$ 35	$ 27	$ 37

Segment Disclosures (Tables)

12 Months Ended

Dec. 31, 2025

Segment Reporting [Abstract]

Reconciliation of revenue from segment to consolidated [Table Text Block]

The following tables present revenues, Modified EBITDA, significant expenses, and certain segment assets measures:


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services (1)		Total
	(Millions)










































































2025
Segment revenues:
Service revenues
External	$	4,731	$	1,980	$	1,621	$	—	$	8,332
Internal	95		15		230		—		340
Total service revenues	4,826		1,995		1,851		—		8,672
Total service revenues – commodity consideration	104		2		86		—		192
Product sales
External	156		49		142		2,776		3,123
Internal	356		122		764		(670)		572
Total product sales	512		171		906		2,106		3,695
Net gain (loss) from commodity derivatives
Realized	1		—		4		(69)		(64)
Unrealized	—		—		—		138		138
Total net gain (loss) from commodity derivatives (2)	1		—		4		69		74
Total revenues of reportable segments	$	5,443	$	2,168	$	2,847	$	2,175	$	12,633
Reconciliation of revenues:
Revenues from upstream operations, corporate, and other business activities									632
Net unrealized gain (loss) from commodity derivatives for upstream operations									10
Eliminations									(1,325)
Total consolidated revenues									$	11,950
Segment costs and expenses and Proportional Modified EBITDA of equity-method investments:
Product costs and net realized processing commodity expenses	(549)		(149)		(876)		(1,811)
Net unrealized gain (loss) from commodity derivatives within Net processing commodity expenses	—		—		—		2
Operating and administrative expenses (3)	(1,142)		(449)		(605)		(93)
Recoverable power, transportation, and storage costs (4)	(247)		(172)		(62)		—
Other segment income (expenses) - net (5)	68		(10)		4		2
Impairment or write-off of certain assets (6)	—		—		(212)		—

Proportional Modified EBITDA of equity-method investments	147		640		142		36
Total Modified EBITDA of reportable segments	$	3,720	$	2,028	$	1,238	$	311	$	7,297
Reconciliation of Modified EBITDA:
Contributions from upstream operations, corporate, and other business activities									376
Depreciation, depletion, and amortization expenses									(2,347)
Equity earnings (losses)									760
Other investing income (loss) - net									42
Interest expense									(1,442)
Accretion expense associated with AROs for nonregulated operations									(96)
Proportional Modified EBITDA of equity-method investments									(965)
Income (loss) before income taxes									$	3,625

Equity-method investments by reportable segment	$	512	$	3,236	$	460	$	292	$	4,500
Other equity-method investments									18
Total equity-method investments									$	4,518

Segment assets	$	26,515	$	12,533	$	12,398	$	317	$	51,763
Total current assets									3,244
Regulatory assets, deferred charges, and other									2,011
Assets of upstream operations, corporate, and other business activities									1,555
Total assets									$	58,573

Additions to long-lived segment assets	$	3,845	$	209	$	1,067	$	1	$	5,122
Additions to long-lived assets of upstream operations, corporate, and other business activities									302
Total additions to long-lived assets									$	5,424


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services (1)		Total
	(Millions)
2024
Segment revenues:
Service revenues
External	$	4,157	$	1,900	$	1,558	$	—	$	7,615
Internal	89		13		160		—		262
Total service revenues	4,246		1,913		1,718		—		7,877
Total service revenues – commodity consideration	54		2		78		—		134
Product sales
External	144		24		178		2,500		2,846
Internal	184		86		691		(448)		513
Total product sales	328		110		869		2,052		3,359
Net gain (loss) from commodity derivatives
Realized	—		—		4		72		76
Unrealized	—		—		—		(335)		(335)
Total net gain (loss) from commodity derivatives (2)	—		—		4		(263)		(259)
Total revenues of reportable segments	$	4,628	$	2,025	$	2,669	$	1,789	$	11,111
Reconciliation of revenues:
Revenues from upstream operations, corporate, and other business activities									470
Net unrealized gain (loss) from commodity derivatives for upstream operations									(26)
Eliminations									(1,052)
Total consolidated revenues									$	10,503
Segment costs and expenses and Proportional Modified EBITDA of equity-method investments:
Product costs and net realized processing commodity expenses	(329)		(88)		(844)		(1,799)
Net unrealized gain (loss) from commodity derivatives within Net processing commodity expenses	—		—		—		(6)
Operating and administrative expenses (3)	(1,104)		(441)		(591)		(108)
Recoverable power, transportation, and storage costs (4)	(250)		(143)		(49)		—
Other segment income (expenses) - net (5)	155		3		(5)		—

Proportional Modified EBITDA of equity-method investments	173		602		132		—
Total Modified EBITDA of reportable segments	$	3,273	$	1,958	$	1,312	$	(124)	$	6,419
Reconciliation of Modified EBITDA:
Contributions from upstream operations, corporate, and other business activities									237

Depreciation, depletion, and amortization expenses									(2,219)
Equity earnings (losses)									560
Other investing income (loss) - net									343
Interest expense									(1,364)
Accretion expense associated with AROs for nonregulated operations									(81)
Proportional Modified EBITDA of equity-method investments									(909)
Income (loss) before income taxes									$	2,986

Equity-method investments by reportable segment	$	272	$	3,346	$	476	$	—	$	4,094
Other equity-method investments									13
Total equity-method investments									$	4,107

Segment assets	$	23,149	$	12,918	$	12,144	$	46	$	48,257
Total current assets									2,661
Regulatory assets, deferred charges, and other									1,830
Assets of upstream operations, corporate, and other business activities									1,784
Total assets									$	54,532

Additions to long-lived segment assets	$	4,399	$	210	$	529	$	2	$	5,140








Additions to long-lived assets of upstream operations, corporate, and other business activities									458
Total additions to long-lived assets									$	5,598


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services (1)		Total
	(Millions)
2023
Segment revenues:
Service revenues
External	$	3,766	$	1,868	$	1,376	$	1	$	7,011
Internal	92		28		126		—		246
Total service revenues	3,858		1,896		1,502		1		7,257
Total service revenues – commodity consideration	38		5		103		—		146
Product sales
External	146		34		80		2,382		2,642
Internal	106		98		361		(322)		243
Total product sales	252		132		441		2,060		2,885
Net gain (loss) from commodity derivatives
Realized	2		—		89		115		206
Unrealized	—		—		—		702		702
Total net gain (loss) from commodity derivatives (2)	2		—		89		817		908
Total revenues of reportable segments	$	4,150	$	2,033	$	2,135	$	2,878	$	11,196
Reconciliation of revenues:
Revenues from upstream operations, corporate, and other business activities									505
Net unrealized gain (loss) from commodity derivatives for upstream operations									1
Eliminations									(795)
Total consolidated revenues									$	10,907
Segment costs and expenses and Proportional Modified EBITDA of equity-method investments:
Product costs and net realized processing commodity expenses	(259)		(125)		(517)		(1,786)
Net unrealized gain (loss) from commodity derivatives within Net processing commodity expenses	—		—		—		(43)
Operating and administrative expenses (3)	(1,034)		(424)		(502)		(98)
Recoverable power, transportation, and storage costs (4)	(241)		(132)		(37)		—
Other segment income (expenses) - net (5)	118		(10)		7		(1)
Impairment or write-off of certain assets	—		—		(10)		—
Gain on sale of business (7)	129		—		—		—
Proportional Modified EBITDA of equity-method investments	205		574		162		—
Total Modified EBITDA of reportable segments	$	3,068	$	1,916	$	1,238	$	950	$	7,172
Reconciliation of Modified EBITDA:
Contributions from upstream operations, corporate, and other business activities									307
Unallocated Net gain from Energy Transfer litigation judgment (8)									534
Depreciation, depletion, and amortization expenses									(2,071)
Equity earnings (losses)									589
Other investing income (loss) - net									108
Interest expense									(1,236)
Accretion expense associated with AROs for nonregulated operations									(59)
Proportional Modified EBITDA of equity-method investments									(939)
Income (loss) before income taxes									$	4,405

Equity-method investments by reportable segment	$	652	$	3,477	$	477	$	—	$	4,606
Other equity-method investments									8
Total equity-method investments									$	4,614

Segment assets	$	19,705	$	13,319	$	12,188	$	77	$	45,289
Total current assets									4,513
Regulatory assets, deferred charges, and other									1,573
Assets of upstream operations, corporate, and other business activities									1,252
Total assets									$	52,627

Additions to long-lived segment assets	$	2,501	$	340	$	1,186	$	7	$	4,034
Additions to long-lived assets of upstream operations, corporate, and other business activities									279
Total additions to long-lived assets									$	4,313

_______________________

(1) As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities.

(2) Williams records transactions that qualify as commodity derivatives at fair value with changes in fair value recognized in earnings in the period of change and characterized as unrealized gains or losses. Gains and losses from commodity derivatives held for energy trading purposes are presented on a net basis in revenue.

(3) Segment operating and administrative expenses primarily include payroll, maintenance and operating costs and taxes, and general and administrative expenses, including acquisition and transition-related expenses. It also includes project execution, information technology, finance and accounting, real estate and aviation, central engineering services, safety and operational discipline, supply chain and digital transformation, corporate strategic development, human resources, legal and government affairs, and executive and audit support services costs which are centrally managed and allocated to segments.

(4) Recoverable power, transportation and storage costs are charges incurred which are reimbursable pursuant to FERC stipulations or customer contracts.

(5) Other segment income (expenses) primarily includes equity AFUDC and regulatory credits and charges related to Williams’ regulated operations.

(6) Impairment or write-off of certain assets primarily includes a $25 million write-off of certain compression assets within the West segment in September 2025 and a $176 million impairment of certain gas gathering assets within the West segment in December 2025 (Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk).

(7) Gain on sale of business reflects a gain recognized on the sale of certain liquids pipelines in the Gulf Coast region in September 2023 (Note 3 – Acquisitions and Divestitures).

(8) Net gain from Energy Transfer litigation judgment resulted from a favorable ruling in November 2023 (Note 1 – Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies).

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2025
Auditor [Line Items]
Auditor Name	Ernst & Young LLP
Auditor Location	Tulsa, Oklahoma
Auditor Firm ID	42
Transcontinental Gas Pipe Line Company, LLC [Member]
Auditor [Line Items]
Auditor Name	Ernst & Young LLP
Auditor Location	Houston, Texas
Auditor Firm ID	42
Northwest Pipeline LLC [Member]
Auditor [Line Items]
Auditor Name	Ernst & Young LLP
Auditor Location	Houston, Texas
Auditor Firm ID	42

Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Accrued Liabilities [Line Items]
Other current liabilities	$ 1,639	$ 1,360
Williams Companies Inc [Member]
Accrued Liabilities [Line Items]
Interest on debt	342	350
Employee costs	283	285
Reserve for rate refunds	179	0
Contract liabilities (Note 5)	165	170
Asset Retirement Obligation, Current	103	91
Operating lease liabilities (Note 14)	32	26
Other, including accrued loss contingencies	$ 418	$ 353
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Transcontinental Gas Pipe Line Company, LLC [Member]
Accrued Liabilities [Line Items]
Interest on debt	$ 53	$ 76
Reserve for rate refunds	179	0
Contract liabilities (Note 5)	11	10
Regulatory Liability, Current	93	58
Asset Retirement Obligation, Current	41	22
Operating lease liabilities (Note 14)	9	6
Customer Deposits	68	45
Taxes Other than Income Taxes, Current	28	27
Other, including accrued loss contingencies	36	23
Other current liabilities	$ 143	$ 105
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Northwest Pipeline LLC [Member]
Accrued Liabilities [Line Items]
Interest on debt	$ 6	$ 6
Regulatory Liability, Current	20	20
Operating lease liabilities (Note 14)	0	1
Taxes Other than Income Taxes, Current	9	8
Transportation and gas exchange payables	5	10
Other, including accrued loss contingencies	12	10
Other current liabilities	$ 32	$ 34
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Other Current Liabilities \| Williams Companies Inc [Member]
Accrued Liabilities [Line Items]
Regulatory Liability, Current	$ 117	$ 85

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Item 1C. Cybersecurity Management for Williams, Transco, and NWP recognizes the increasing volume and sophistication of cyber threats and takes its responsibility to protect the information and systems under its purview seriously. Management’s cybersecurity processes aim to provide a comprehensive approach to assess, identify, and manage material risks arising from these cybersecurity threats. Comprehensive Cybersecurity Program: Management has implemented a comprehensive cybersecurity risk management program (Cybersecurity Program) that is aligned with the National Institute for Standards and Technology Cybersecurity Framework. The Cybersecurity Program provides a risk-based approach to cybersecurity, and security controls are tailored so that cost-effective controls can be applied commensurate with the risk and sensitivity of specific information systems, control systems, and enterprise data. The Cybersecurity Program incorporates best practices and industry standards from multiple sources and is designed to comply with applicable regulations. The Cybersecurity Program includes, but is not limited to, the following elements: risk assessment, policies and procedures, contract management, training and awareness, auditing, compliance monitoring and testing, table-top exercises, and incident response. Integration with Overall Risk Management: Management’s cybersecurity processes have been integrated into the overall risk management system and processes. Management considers cybersecurity threat risks alongside other company risks as part of its overall risk assessment process. Cybersecurity risk professionals collaborate with subject matter specialists, as necessary, to gather insights for identifying and assessing material cybersecurity threat risks, their severity, and potential mitigations. Engagement of Third Parties: Management often engages with specialized third-party assessors, consultants, auditors, and other experts to review, validate, and enhance its cybersecurity practices. Third-party independent assessments provide an external perspective on management’s cybersecurity posture, allowing it to leverage best practices from the industry and ensure its defenses remain robust. All third parties engaged for such processes are subjected to rigorous scrutiny to ensure the third parties meet management’s security standards. Oversight of Third-party Service Providers: Management acknowledges the potential risks associated with the use of third-party service providers. Therefore, management has established processes to oversee and identify material cybersecurity risks that may be associated with third-party service providers with whom it engages. This includes conducting thorough, risk-based due diligence before onboarding, performing security assessments, and confirming adherence to management’s cybersecurity requirements. Management also maintains active communication channels with these providers to stay informed about any potential security incidents or concerns. Disclosure of Risks: Management describes how risks from cybersecurity threats could materially affect its business strategy, results of operations, or financial condition, as part of its risk factor disclosures at Part I, Item 1A. Risk Factors of this Annual Report on Form 10-K. To date, Williams has not experienced any cybersecurity threats or incidents that have resulted in a material adverse effect on our business strategy, results of operations, or financial condition. However, management continues to monitor and assess risks that could have a material impact in the future. Management is committed to continually enhancing its cybersecurity processes and practices to address the dynamic nature of the threats it faces and to ensure the security and integrity of its systems and data. Cybersecurity Governance Cybersecurity is an important part of the risk management processes and an area of focus for the Board of Directors and management. Each member of Williams’ organization, which includes Transco and NWP, from facility operators to board members, has a responsibility to safeguard the organization’s cybersecurity. The Chief Information Security Officer (CISO) collaborates with internal stakeholders to develop, implement and maintain the Cybersecurity Program, ensuring that the program addresses the evolving cybersecurity risk landscape. The CISO also engages with executive leadership to ensure that cybersecurity remains integrated with Williams’ overall risk management and strategic objectives. The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity. Management has implemented processes and controls designed to prevent, detect, mitigate, and remediate cybersecurity incidents, ensuring ongoing protection of the company’s systems and data. Additionally, management has protocols by which cybersecurity incidents that meet established reporting thresholds are escalated internally and, where appropriate, are reported to the Board, as well as ongoing updates regarding any such incident until it has been addressed. Williams’ CIO, who joined the company in February 2025, brings over 20 years of experience in information technology and leadership within the energy industry. He has extensive expertise in digital transformation, cloud strategies, enterprise artificial intelligence initiatives, and cybersecurity, as well as managing large-scale system implementations and integrations. He holds an Executive Master of Business Administration from the University of Texas at San Antonio, a Master of Computer Science and Engineering from the University of Texas at Arlington, and a Bachelor of Information Science and Engineering from Bangalore University. Williams’ CISO joined the company in November 2025, bringing significant experience in cybersecurity and operational technology leadership within the energy industry. He holds a Bachelor of Science in Management Information Systems from Kansas State University and is a Certified Information Systems Security Professional. His expertise spans operational technology security, infrastructure management, and cybersecurity operations. At Williams, he is responsible for the company’s cybersecurity strategy and execution, ensuring robust protection of systems and data in a dynamic threat environment.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	Integration with Overall Risk Management: Management’s cybersecurity processes have been integrated into the overall risk management system and processes. Management considers cybersecurity threat risks alongside other company risks as part of its overall risk assessment process. Cybersecurity risk professionals collaborate with subject matter specialists, as necessary, to gather insights for identifying and assessing material cybersecurity threat risks, their severity, and potential mitigations.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Text Block]	Disclosure of Risks: Management describes how risks from cybersecurity threats could materially affect its business strategy, results of operations, or financial condition, as part of its risk factor disclosures at Part I, Item 1A. Risk Factors of this Annual Report on Form 10-K. To date, Williams has not experienced any cybersecurity threats or incidents that have resulted in a material adverse effect on our business strategy, results of operations, or financial condition. However, management continues to monitor and assess risks that could have a material impact in the future. Management is committed to continually enhancing its cybersecurity processes and practices to address the dynamic nature of the threats it faces and to ensure the security and integrity of its systems and data.
Cybersecurity Risk Board of Directors Oversight [Text Block]	Cybersecurity Governance Cybersecurity is an important part of the risk management processes and an area of focus for the Board of Directors and management. Each member of Williams’ organization, which includes Transco and NWP, from facility operators to board members, has a responsibility to safeguard the organization’s cybersecurity. The Chief Information Security Officer (CISO) collaborates with internal stakeholders to develop, implement and maintain the Cybersecurity Program, ensuring that the program addresses the evolving cybersecurity risk landscape. The CISO also engages with executive leadership to ensure that cybersecurity remains integrated with Williams’ overall risk management and strategic objectives. The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity. Management has implemented processes and controls designed to prevent, detect, mitigate, and remediate cybersecurity incidents, ensuring ongoing protection of the company’s systems and data. Additionally, management has protocols by which cybersecurity incidents that meet established reporting thresholds are escalated internally and, where appropriate, are reported to the Board, as well as ongoing updates regarding any such incident until it has been addressed. Williams’ CIO, who joined the company in February 2025, brings over 20 years of experience in information technology and leadership within the energy industry. He has extensive expertise in digital transformation, cloud strategies, enterprise artificial intelligence initiatives, and cybersecurity, as well as managing large-scale system implementations and integrations. He holds an Executive Master of Business Administration from the University of Texas at San Antonio, a Master of Computer Science and Engineering from the University of Texas at Arlington, and a Bachelor of Information Science and Engineering from Bangalore University. Williams’ CISO joined the company in November 2025, bringing significant experience in cybersecurity and operational technology leadership within the energy industry. He holds a Bachelor of Science in Management Information Systems from Kansas State University and is a Certified Information Systems Security Professional. His expertise spans operational technology security, infrastructure management, and cybersecurity operations. At Williams, he is responsible for the company’s cybersecurity strategy and execution, ensuring robust protection of systems and data in a dynamic threat environment.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity. Management has implemented processes and controls designed to prevent, detect, mitigate, and remediate cybersecurity incidents, ensuring ongoing protection of the company’s systems and data. Additionally, management has protocols by which cybersecurity incidents that meet established reporting thresholds are escalated internally and, where appropriate, are reported to the Board, as well as ongoing updates regarding any such incident until it has been addressed.
Cybersecurity Risk Role of Management [Text Block]	Cybersecurity is an important part of the risk management processes and an area of focus for the Board of Directors and management. Each member of Williams’ organization, which includes Transco and NWP, from facility operators to board members, has a responsibility to safeguard the organization’s cybersecurity. The Chief Information Security Officer (CISO) collaborates with internal stakeholders to develop, implement and maintain the Cybersecurity Program, ensuring that the program addresses the evolving cybersecurity risk landscape. The CISO also engages with executive leadership to ensure that cybersecurity remains integrated with Williams’ overall risk management and strategic objectives.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	The Chief Information Security Officer (CISO) collaborates with internal stakeholders to develop, implement and maintain the Cybersecurity Program, ensuring that the program addresses the evolving cybersecurity risk landscape. The CISO also engages with executive leadership to ensure that cybersecurity remains integrated with Williams’ overall risk management and strategic objectives. The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Williams’ CIO, who joined the company in February 2025, brings over 20 years of experience in information technology and leadership within the energy industry. He has extensive expertise in digital transformation, cloud strategies, enterprise artificial intelligence initiatives, and cybersecurity, as well as managing large-scale system implementations and integrations. He holds an Executive Master of Business Administration from the University of Texas at San Antonio, a Master of Computer Science and Engineering from the University of Texas at Arlington, and a Bachelor of Information Science and Engineering from Bangalore University. Williams’ CISO joined the company in November 2025, bringing significant experience in cybersecurity and operational technology leadership within the energy industry. He holds a Bachelor of Science in Management Information Systems from Kansas State University and is a Certified Information Systems Security Professional. His expertise spans operational technology security, infrastructure management, and cybersecurity operations. At Williams, he is responsible for the company’s cybersecurity strategy and execution, ensuring robust protection of systems and data in a dynamic threat environment.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	The Board of Directors oversees cybersecurity-related policy and strategy. As part of this oversight, the CISO provides a cybersecurity dashboard that is reviewed by the Board annually, which includes key performance indicators for cybersecurity process maturity, operational performance, and enterprise performance toward TSA compliance. Additionally, the Audit Committee, comprised of independent directors, reviews the implementation and effectiveness of cybersecurity risk management protocol as part of the company’s accounting and internal control policies. As part of this oversight, the Chief Information Officer (CIO) presents to the Audit Committee bi-annually, as well as periodically in conjunction with any internal audits related to cybersecurity. Management has implemented processes and controls designed to prevent, detect, mitigate, and remediate cybersecurity incidents, ensuring ongoing protection of the company’s systems and data. Additionally, management has protocols by which cybersecurity incidents that meet established reporting thresholds are escalated internally and, where appropriate, are reported to the Board, as well as ongoing updates regarding any such incident until it has been addressed.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Commodity Derivatives (Tables)

12 Months Ended

Dec. 31, 2025

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivative Instruments

At December 31, 2025, the notional volume of the net long (short) positions for Williams’ commodity derivative contracts were as follows:

Commodity

Unit of Measure

Net Long (Short) Position

Index Risk

Natural Gas

MMBtu

1,110,264,783

Central Hub Risk - Henry Hub

Natural Gas

MMBtu

(10,941,340)

Basis Risk

Natural Gas

MMBtu

502,600,784

Central Hub Risk - Mont Belvieu

Natural Gas Liquids

Barrels

(456,000)

Basis Risk

Natural Gas Liquids

Barrels

50,000

Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location

The fair value of commodity derivatives, which are not designated as hedging instruments for accounting purposes, is reflected as follows:


	December 31, 2025				December 31, 2024
Commodity Derivatives Categories	Assets		(Liabilities)		Assets		(Liabilities)
	(Millions)





Current	$	494	$	(535)	$	508	$	(635)
Noncurrent	228		(380)		218		(435)
Total commodity derivatives	722		(915)		726		(1,070)
Counterparty and collateral netting offset	(386)		575		(382)		670
Amounts recognized in Williams’ Consolidated Balance Sheet	$	336	$	(340)	$	344	$	(400)

The pre-tax impacts of Williams’ commodity derivatives, which are not designated as hedging instruments for accounting purposes, are reflected as follows:


	Year Ended December 31,

	2025		2024		2023
	(Millions)
Net gain (loss) from commodity derivatives within Total revenues:

Realized	$	(28)	$	111	$	253
Unrealized	148		(361)		703
	$	120	$	(250)	$	956

Net gain (loss) from commodity derivatives within Net processing commodity expenses:
Realized	$	(3)	$	(8)	$	(4)
Unrealized	2		(6)		(43)
	$	(1)	$	(14)	$	(47)
Total net gain (loss) from commodity derivatives	$	119	$	(264)	$	909

Property, Plant, and Equipment (Details ARO) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Unusual or Infrequent Item [Line Items]
Asset Retirement Obligation, Liabilities Incurred	$ 23	$ 474
Regulatory Assets	698	666
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	2,639	2,084
Liabilities incurred, including acquisitions	23	474
Liabilities settled	(110)	(68)
Accretion	133	118
Revisions	(57)	31
Balance at end of year	2,587	2,639
South Mansfield Upstream Interests And Gas Gathering Assets In Mid Continent Region
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Liabilities settled	(41)	0
Transcontinental Gas Pipe Line Company, LLC [Member]
Unusual or Infrequent Item [Line Items]
Asset Retirement Obligations, Noncurrent	573	593
Asset Retirement Obligation, Liabilities Incurred	9	0
Regulatory Assets	394	394
Regulatory Liabilities, Noncurrent	914	976
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	615	619
Liabilities incurred, including acquisitions	9	0
Liabilities settled	(44)	(32)
Accretion	29	29
Revisions	5	(1)
Balance at end of year	614	615
Transcontinental Gas Pipe Line Company, LLC [Member] \| Removal Costs
Unusual or Infrequent Item [Line Items]
Regulatory Liabilities, Noncurrent	592	632
Northwest Pipeline LLC [Member]
Unusual or Infrequent Item [Line Items]
Asset Retirement Obligations, Noncurrent	152	144
Regulatory Assets	83	55
Regulatory Liabilities, Noncurrent	225	233
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of year	144	136
Accretion	8	8
Balance at end of year	152	144
Northwest Pipeline LLC [Member] \| Removal Costs
Unusual or Infrequent Item [Line Items]
Regulatory Liabilities, Noncurrent	35	30
Northwest Pipeline LLC [Member] \| Asset Retirement Obligation Costs [Member]
Unusual or Infrequent Item [Line Items]
Regulatory Assets	132	124
Regulatory liabilities, deferred income, and other [Member]
Unusual or Infrequent Item [Line Items]
Asset Retirement Obligations, Noncurrent	2,490	2,550
Regulatory Liabilities, Noncurrent	$ 1,202	$ 1,300

Related Party Transactions - Williams (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Revenues	$ 11,950	$ 10,503	$ 10,907
Receivables, Net, Current	2,084	1,863
Accounts payable	2,224	1,613
Investee
Related Party Transaction [Line Items]
Revenues	20	2	5
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	180	266	776
Receivables, Net, Current	4	1
Accounts payable	14	19
OperatingFeesAndCostsBilledToThirdParty	73	52	64
Director
Related Party Transaction [Line Items]
Revenues	97	59	90
Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	$ 44	$ 40	$ 25

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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+ Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Commodity Derivatives - Contingent Features (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Additional Collateral, Aggregate Fair Value	$ 30
Collateral Already Posted, Aggregate Fair Value	$ 189	$ 288

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Revenue by Category (Details) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

$ 14,899

$ 12,632

$ 11,996

Revenue Not from Contract with Customer, Other

^[1]

3,454

2,348

4,537

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

(6,403)

(4,477)

(5,626)

Total revenues

11,950

10,503

10,907

Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

3,721

3,419

3,274

NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

4,372

3,970

3,533

NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

192

134

146

Total revenues

192

134

146

Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

155

140

115

Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

8,440

7,663

7,068

Total revenues

8,348

7,628

7,026

Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

6,459

4,969

4,928

Total revenues

3,290

2,991

2,779

Operating Segments [Member] | Transmission, Power & Gulf [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

5,404

4,589

4,097

Revenue Not from Contract with Customer, Other

^[1]

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

Total revenues

5,443

4,628

4,150

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

3,804

3,500

3,334

Operating Segments [Member] | Transmission, Power & Gulf [Member] | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

933

661

443

Operating Segments [Member] | Transmission, Power & Gulf [Member] | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

104

Total revenues

104

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

4,892

4,261

3,845

Total revenues

4,826

4,246

3,858

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

512

328

252

Total revenues

512

328

252

Operating Segments [Member] | Northeast G & P [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

2,122

1,982

2,006

Revenue Not from Contract with Customer, Other

^[1]

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

Total revenues

2,168

2,025

2,033

Operating Segments [Member] | Northeast G & P [Member] | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Northeast G & P [Member] | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

1,850

1,778

1,782

Operating Segments [Member] | Northeast G & P [Member] | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Total revenues

Operating Segments [Member] | Northeast G & P [Member] | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Northeast G & P [Member] | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

1,951

1,872

1,874

Total revenues

1,995

1,913

1,896

Operating Segments [Member] | Northeast G & P [Member] | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

171

110

132

Total revenues

171

110

132

Operating Segments [Member] | West [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

2,840

2,661

2,034

Revenue Not from Contract with Customer, Other

^[1]

101

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

Total revenues

2,847

2,669

2,135

Operating Segments [Member] | West [Member] | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | West [Member] | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

1,824

1,693

1,478

Operating Segments [Member] | West [Member] | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

103

Total revenues

103

Operating Segments [Member] | West [Member] | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | West [Member] | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

1,934

1,792

1,593

Total revenues

1,851

1,718

1,502

Operating Segments [Member] | West [Member] | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

906

869

441

Total revenues

906

869

441

Operating Segments [Member] | Gas & NGL Marketing Services

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

6,047

4,530

4,616

Revenue Not from Contract with Customer, Other

^[1]

3,303

2,236

4,294

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

(7,175)

(4,977)

(6,032)

Total revenues

^[3]

2,175

1,789

2,878

Operating Segments [Member] | Gas & NGL Marketing Services | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Gas & NGL Marketing Services | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Gas & NGL Marketing Services | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Total revenues

^[3]

Operating Segments [Member] | Gas & NGL Marketing Services | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Operating Segments [Member] | Gas & NGL Marketing Services | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Total revenues

^[3]

Operating Segments [Member] | Gas & NGL Marketing Services | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

6,047

4,530

4,615

Total revenues

^[3]

2,106

2,052

2,060

Corporate, Non-Segment | Other Operating Segment

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

581

420

442

Revenue Not from Contract with Customer, Other

^[1]

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

Total revenues

642

444

506

Corporate, Non-Segment | Other Operating Segment | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Corporate, Non-Segment | Other Operating Segment | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Corporate, Non-Segment | Other Operating Segment | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Corporate, Non-Segment | Other Operating Segment | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Corporate, Non-Segment | Other Operating Segment | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Corporate, Non-Segment | Other Operating Segment | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

580

420

442

Intersegment Eliminations [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

(2,095)

(1,550)

(1,199)

Revenue Not from Contract with Customer, Other

^[1]

(2)

Revenues Adjustments For Certain Risk Management Activities Costs

^[2]

772

500

406

Total revenues

(1,325)

(1,052)

(795)

Intersegment Eliminations [Member] | Regulated Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

(83)

(81)

(60)

Intersegment Eliminations [Member] | NonRegulated Service Monetary Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

(235)

(162)

(170)

Intersegment Eliminations [Member] | NonRegulated Service Commodity Consideration [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

Intersegment Eliminations [Member] | Other Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

(20)

(19)

(15)

Intersegment Eliminations [Member] | Service [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

(338)

(262)

(245)

Intersegment Eliminations [Member] | Product [Member]

Disaggregation of Revenue [Line Items]

Revenue from Contract with Customer, Excluding Assessed Tax

$ (1,757)

$ (1,288)

$ (954)

[1]	Revenues not derived from contracts with customers primarily consist of physical product sales related to commodity derivative contracts, realized and unrealized gains and losses associated with Williams’ commodity derivative contracts, which are reported in Net gain (loss) from commodity derivatives in the Consolidated Statement of Income, management fees received for certain services provided to operated equity-method investments, and leasing revenues associated with the Williams headquarters building.
[2]	Other adjustments reflect certain costs of Gas & NGL Marketing Services’ risk management activities. As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities in the Consolidated Statement of Income.
[3]	As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities.

Statement of Changes in Member's Equity - Transco - USD ($) $ in Millions	Total	Transcontinental Gas Pipe Line Company, LLC [Member]	Member's Capital Transcontinental Gas Pipe Line Company, LLC [Member]	Retained Earnings Transcontinental Gas Pipe Line Company, LLC [Member]
Balance at beginning of period at Dec. 31, 2022			$ 5,088	$ 3,022
Net income	$ 3,179			1,247
Cash distributions to parent		$ 1,220		(1,220)
Balance at end of period at Dec. 31, 2023		8,137	5,088	3,049
Net income	2,225			1,313
Cash distributions to parent		1,145		(1,145)
Balance at end of period at Dec. 31, 2024		8,305	5,088	3,217
Net income	$ 2,618			1,426
Cash distributions to parent		1,340		(1,340)
Balance at end of period at Dec. 31, 2025		$ 8,391	$ 5,088	$ 3,303

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Provision (Benefit) for Income Taxes Reconciliations to Recorded Tax Provision (Benefit) Table (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Effective Income Tax Rate Reconciliation [Abstract]
Tax Jurisdiction of Domicile [Extensible Enumeration]	UNITED STATES	UNITED STATES	UNITED STATES
Provision (benefit) at statutory rate	$ 761	$ 627	$ 925
Increases Decreases In Taxes Resulting From [Abstract]
State and local income tax, net of federal income tax effect	130	35	104
Nontaxable or nondeductible items	(34)	(23)	(23)
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	0	1	(1)
Less: Provision (benefit) for income taxes	$ 857	$ 640	$ 1,005
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	3.60%	1.20%	2.40%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent	(0.90%)	(0.80%)	(0.50%)
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	0.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Percent	23.70%	21.40%	22.90%

Balance Sheet - NWP - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Assets, Current [Abstract]
Cash and cash equivalents	$ 63	$ 60
Inventory, Net	314	279
Other current assets and deferred charges	256	191
Current assets	3,244	2,661
Property, Plant and Equipment, Net	41,996	38,692
Other Assets, Noncurrent	2,011	1,830
Total assets	58,573	54,532
Liabilities, Current [Abstract]
Accounts payable	2,224	1,613
Other current liabilities	1,639	1,360
Total current liabilities	6,106	5,312
Contingent liabilities and commitments
Members' Equity [Abstract]
Retained Earnings (Accumulated Deficit)	(12,237)	(12,396)
Total liabilities and equity	58,573	54,532
Northwest Pipeline LLC [Member]
Assets, Current [Abstract]
Cash and cash equivalents	0	0
Accounts and Other Receivables, Net, Current	1	2
Inventory, Net	9	9
Regulatory Assets, Current	3	6
Other current assets and deferred charges	8	6
Current assets	280	62
Property, Plant and Equipment, Net	2,270	2,129
Regulatory Assets, Noncurrent	80	49
Other Assets, Noncurrent	30	29
Total assets	2,660	2,269
Liabilities, Current [Abstract]
Accounts Payable, Trade, Current	39	48
Regulatory Liability, Current	20	20
Other current liabilities	32	34
Long-Term Debt, Current Maturities	0	85
Total current liabilities	103	225
Long-Term Debt, Excluding Current Maturities	748	497
Regulatory Liabilities, Noncurrent	225	233
Asset Retirement Obligations, Noncurrent	152	144
Other Liabilities, Noncurrent	5	7
Contingent liabilities and commitments
Members' Equity [Abstract]
Members' Capital	1,305	1,074
Retained Earnings (Accumulated Deficit)	122	89
Total Members' Equity	1,427	1,163
Total liabilities and equity	2,660	2,269
Northwest Pipeline LLC [Member] \| Related Party
Assets, Current [Abstract]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current	218	0
Liabilities, Current [Abstract]
Accounts payable	12	12
Northwest Pipeline LLC [Member] \| Nonrelated Party
Assets, Current [Abstract]
Accounts Receivable, after Allowance for Credit Loss, Current	41	39
Northwest Pipeline LLC [Member] \| Affiliated Entity
Liabilities, Current [Abstract]
Accounts payable	$ 0	$ 26

Consolidated Statement of Cash Flows - Williams - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
OPERATING ACTIVITIES:
Net income (loss)	$ 2,768	$ 2,346	$ 3,303
Adjustments to reconcile to net cash provided (used) by operating activities:
Depreciation, depletion, and amortization	2,347	2,219	2,071
Provision (benefit) for deferred income taxes	744	506	951
Equity (earnings) losses	(760)	(560)	(589)
Distributions from equity-method investees (Note 8)	800	789	796
Other Asset Impairment Charges	212	0	10
Net unrealized (gain) loss from commodity derivative instruments	(150)	367	(660)
Gain on sale of business (Note 3)	0	0	(129)
Gain on disposition of equity-method investments (Note 8)	0	(149)	0
Gain on remeasurement of equity-method investments (Note 3)	0	(127)	(30)
Inventory write-downs	8	10	30
Amortization of stock-based awards	93	99	77
Cash provided (used) by changes in current assets and liabilities:
Accounts receivable	(219)	(169)	1,089
Inventories	(45)	(9)	13
Other current assets and deferred charges	(71)	9	60
Accounts payable	115	139	(1,009)
Other current liabilities	170	35	(19)
Changes in current and noncurrent commodity derivative assets and liabilities	99	(286)	200
Other, including changes in noncurrent assets and liabilities	(213)	(245)	(226)
Net cash provided (used) by operating activities	5,898	4,974	5,938
FINANCING ACTIVITIES:
Proceeds from (payments of) commercial paper – net	245	(269)	372
Proceeds from long-term debt	4,940	3,594	2,755
Payments of long-term debt	(2,827)	(2,946)	(634)
Payments for debt issuance costs	(45)	(32)	(23)
Proceeds from issuance of common stock	9	10	6
Purchases of treasury stock	0	0	(130)
Common dividends paid	(2,442)	(2,316)	(2,179)
Dividends and distributions paid to noncontrolling interests	(259)	(242)	(213)
Contributions from noncontrolling interests	36	36	18
Other – net	(63)	(36)	(21)
Net cash provided (used) by financing activities	(406)	(2,201)	(49)
INVESTING ACTIVITIES:
Capital expenditures (1)	(4,893)	(2,573)	(2,516)
Dispositions – net	(106)	(105)	(51)
Proceeds from sale of business (Note 3)	0	0	346
Purchases of businesses, net of cash acquired (Note 3)	(1)	(2,244)	(1,568)
Proceeds from dispositions of equity-method investments (Note 8)	0	161	0
Purchases of and contributions to equity-method investments (Note 8)	(511)	(114)	(141)
Other – net	22	12	39
Net cash provided (used) by investing activities	(5,489)	(4,863)	(3,891)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	3	(2,090)	1,998
Cash and cash equivalents at beginning of year	60	2,150	152
Cash and cash equivalents at end of year	63	60	2,150
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
(1) Increases to property, plant, and equipment	(5,375)	(2,581)	(2,564)
Changes in related accounts payable and accrued liabilities	482	8	48
Capital expenditures	$ (4,893)	$ (2,573)	$ (2,516)

Revenue Recognition

12 Months Ended

Dec. 31, 2025

Revenue Recognition [Abstract]

Revenue Recognition [Text Block]

Note 5 – Revenue Recognition

Revenue by Category

The following tables present Williams’ revenue disaggregated by major service line:


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services		Other		Eliminations		Total
	(Millions)






























2025
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,804	$	—	$	—	$	—	$	—	$	(83)	$	3,721
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	933		1,850		1,824		—		—		(235)		4,372
Commodity consideration	104		2		86		—		—		—		192
Other	51		99		24		—		1		(20)		155
Total service revenues	4,892		1,951		1,934		—		1		(338)		8,440
Product sales	512		171		906		6,047		580		(1,757)		6,459
Total revenues from contracts with customers	5,404		2,122		2,840		6,047		581		(2,095)		14,899
Other revenues (1)	39		46		7		3,303		61		(2)		3,454
Other adjustments (2)	—		—		—		(7,175)		—		772		(6,403)
Total revenues	$	5,443	$	2,168	$	2,847	$	2,175	$	642	$	(1,325)	$	11,950

2024
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,500	$	—	$	—	$	—	$	—	$	(81)	$	3,419
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	661		1,778		1,693		—		—		(162)		3,970
Commodity consideration	54		2		78		—		—		—		134
Other	46		92		21		—		—		(19)		140
Total service revenues	4,261		1,872		1,792		—		—		(262)		7,663
Product sales	328		110		869		4,530		420		(1,288)		4,969
Total revenues from contracts with customers	4,589		1,982		2,661		4,530		420		(1,550)		12,632
Other revenues (1)	39		43		8		2,236		24		(2)		2,348
Other adjustments (2)	—		—		—		(4,977)		—		500		(4,477)
Total revenues	$	4,628	$	2,025	$	2,669	$	1,789	$	444	$	(1,052)	$	10,503


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services		Other		Eliminations		Total
	(Millions)
2023
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,334	$	—	$	—	$	—	$	—	$	(60)	$	3,274
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	443		1,782		1,478		—		—		(170)		3,533
Commodity consideration	38		5		103		—		—		—		146
Other	30		87		12		1		—		(15)		115
Total service revenues	3,845		1,874		1,593		1		—		(245)		7,068
Product sales	252		132		441		4,615		442		(954)		4,928
Total revenues from contracts with customers	4,097		2,006		2,034		4,616		442		(1,199)		11,996
Other revenues (1)	53		27		101		4,294		64		(2)		4,537
Other adjustments (2)	—		—		—		(6,032)		—		406		(5,626)
Total revenues	$	4,150	$	2,033	$	2,135	$	2,878	$	506	$	(795)	$	10,907

______________

(1)Revenues not derived from contracts with customers primarily consist of physical product sales related to commodity derivative contracts, realized and unrealized gains and losses associated with Williams’ commodity derivative contracts, which are reported in Net gain (loss) from commodity derivatives in the Consolidated Statement of Income, management fees received for certain services provided to operated equity-method investments, and leasing revenues associated with the Williams headquarters building.

(2)Other adjustments reflect certain costs of Gas & NGL Marketing Services’ risk management activities. As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities in the Consolidated Statement of Income.

For Transco and NWP, revenue disaggregation by major service line includes Natural gas transportation, Natural gas storage, Natural gas product sales, and Other, which are separately presented in their Statements of Net Income.

Contract Assets

The following table presents a reconciliation of contract assets:













	Year Ended December 31,
	Williams				Transco				NWP
	2025		2024		2025		2024		2025		2024
	(Millions)
Balance at beginning of year	$	98	$	36	$	10	$	—	$	21	$	17
Revenue recognized in excess of amounts invoiced	86		170		5		10		6		6
Contract assets acquired	—		36		—		—		—		—
Minimum volume commitments invoiced	(58)		(144)		—		—		—		—
Amortization of contract assets	(17)		—		(2)		—		(3)		(2)
Balance at end of year	$	109	$	98	$	13	$	10	$	24	$	21

Contract Liabilities

The following table presents a reconciliation of contract liabilities:














	Year Ended December 31,
	Williams				Transco				NWP
	2025		2024		2025		2024		2025		2024
	(Millions)
Balance at beginning of year	$	1,046	$	1,081	$	173	$	184	$	—	$	2
Payments received and deferred	198		183		—		—		—		—
Liabilities acquired and other additions	23		53		—		—		—		—
Significant financing component	7		8		—		—		—		—
Liabilities reclassified as held for sale	(19)		—		—		—		—		—
Recognized in revenue	(307)		(279)		(10)		(11)		—		(2)
Balance at end of year	$	948	$	1,046	$	163	$	173	$	—	$	—

Remaining Performance Obligations

Remaining performance obligations primarily include reservation charges on contracted capacity for Williams’ gas pipeline firm transportation contracts with customers, storage capacity contracts, long-term contracts containing MVC associated with midstream businesses, and fixed payments associated with offshore gathering and transportation. For Williams’ interstate natural gas pipeline businesses, including Transco and NWP, remaining performance obligations generally reflect the expected rates for such services for the life of the related contracts; however, these rates may change based on future tariffs approved by the FERC.

Remaining performance obligations exclude variable consideration, including contracts with variable consideration for which it has elected the practical expedient for consideration recognized in revenue as billed. Certain of its contracts contain evergreen and other renewal provisions for periods beyond the initial term of the contract. The remaining performance obligation amounts as of December 31, 2025, do not consider potential future performance obligations for which the renewal has not been exercised and exclude contracts with customers for which the underlying facilities have not received FERC authorization to be placed into service. Consideration received prior to December 31, 2025, that will be recognized in future periods is also excluded from its remaining performance obligations and is instead reflected in contract liabilities.

The following tables present the amount of the contract liabilities balance expected to be recognized as revenue when performance obligations are satisfied and the transaction price allocated to the remaining performance obligations under certain contracts as of December 31, 2025.


	Contract Liabilities
	Williams		Transco		NWP
	(Millions)
2026 (one year)	$	169	$	10	$	—
2027 (one year)	145		10		—
2028 (one year)	120		11		—
2029 (one year)	91		11		—
2030 (one year)	68		10		—
Thereafter	355		111		—
Total	$	948	$	163	$	—


	Remaining Performance Obligations
	Williams		Transco		NWP
	(Millions)
2026 (one year)	$	4,589	$	2,990	$	399
2027 (one year)	4,265		2,772		386
2028 (one year)	3,865		2,576		367
2029 (one year)	2,970		1,846		348
2030 (one year)	2,703		1,759		342
Thereafter	13,779		9,990		1,919
Total	$	32,171	$	21,933	$	3,761

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

Regulatory Assets and Liabilities - Transco (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	$ 698	$ 666
Regulatory Liability [Line Items]
Regulatory Liabilities	1,319	1,385
Transcontinental Gas Pipe Line Company, LLC [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	126	74
Regulatory Assets, Noncurrent	268	320
Regulatory Assets	394	394
Regulatory Liability [Line Items]
Regulatory Liability, Current	93	58
Regulatory Liabilities, Noncurrent	914	976
Regulatory Liabilities	1,007	1,034
Transcontinental Gas Pipe Line Company, LLC [Member] \| Deferred Income Tax Charge
Regulatory Liability [Line Items]
Regulatory Liability, Current	18	31
Regulatory Liabilities, Noncurrent	246	252
Transcontinental Gas Pipe Line Company, LLC [Member] \| Postretirement Benefit Costs
Regulatory Liability [Line Items]
Regulatory Liability, Current	5	0
Regulatory Liabilities, Noncurrent	22	31
Transcontinental Gas Pipe Line Company, LLC [Member] \| Electric Power Cost
Regulatory Liability [Line Items]
Regulatory Liability, Current	59	26
Transcontinental Gas Pipe Line Company, LLC [Member] \| Pension Costs
Regulatory Liability [Line Items]
Regulatory Liability, Current	5	0
Regulatory Liabilities, Noncurrent	22	30
Transcontinental Gas Pipe Line Company, LLC [Member] \| Other Regulatory Assets (Liabilities)
Regulatory Liability [Line Items]
Regulatory Liability, Current	1	1
Regulatory Liabilities, Noncurrent	25	24
Transcontinental Gas Pipe Line Company, LLC [Member] \| Removal Costs
Regulatory Liability [Line Items]
Regulatory Liabilities, Noncurrent	592	632
Transcontinental Gas Pipe Line Company, LLC [Member] \| Sentinel Meter Station Depreciation
Regulatory Liability [Line Items]
Regulatory Liabilities, Noncurrent	7	7
Transcontinental Gas Pipe Line Company, LLC [Member] \| Fuel Cost
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	70	47
Transcontinental Gas Pipe Line Company, LLC [Member] \| Asset Retirement Obligation Costs [Member]
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	51	16
Regulatory Assets, Noncurrent	195	243
Transcontinental Gas Pipe Line Company, LLC [Member] \| Deferred Cash Out
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	0	6
Transcontinental Gas Pipe Line Company, LLC [Member] \| Asset Retirement Costs - Eminence
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Current	5	5
Regulatory Assets, Noncurrent	10	15
Transcontinental Gas Pipe Line Company, LLC [Member] \| Deferred Taxes On Equity Funds Used During Construction
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Noncurrent	28	29
Transcontinental Gas Pipe Line Company, LLC [Member] \| Slug Catcher
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Noncurrent	6	6
Transcontinental Gas Pipe Line Company, LLC [Member] \| Other Regulatory Assets (Liabilities)
Regulatory Assets and Liabilities [Line Items]
Regulatory Assets, Noncurrent	$ 29	$ 27

Other Current Liabilities (Tables)

12 Months Ended

Dec. 31, 2025

Accrued Liabilities, Current [Abstract]

Other Current Liabilities [Table Text Block]

Williams


	December 31,
	2025		2024
	(Millions)
Interest on debt	$	342	$	350
Employee costs	283		285
Reserve for rate refunds (Note 18)	179		—
Contract liabilities (Note 5)	165		170

Regulatory liabilities (Note 10)	117		85
Asset retirement obligations (Note 9)	103		91
Operating lease liabilities (Note 14)	32		26

Other, including accrued loss contingencies	418		353
	$	1,639	$	1,360

Transco


	December 31,
	2025		2024
	(Millions)

Customer deposits	$	68	$	45
Taxes, other than income taxes	28		27
Contract liabilities	11		10
Other	36		23

	$	143	$	105

NWP


	December 31,
	2025		2024
	(Millions)
Taxes, other than income taxes	$	9	$	8
Interest on debt	6		6
Transportation and gas exchange payables	5		10
Other	12		10

	$	32	$	34

Schedule II - Valuation and Qualifying Accounts

12 Months Ended

Dec. 31, 2025

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

Schedule II - Valuation and Qualifying Accounts [Text Block]

The Williams Companies, Inc.

Schedule II — Valuation and Qualifying Accounts


			Additions
	Beginning Balance		Charged (Credited) To Costs and Expenses		Other		Deductions		Ending Balance
	(Millions)
2025
Deferred tax asset valuation allowance (1)	$	91	$	(8)	$	—	$	—	$	83
2024
Deferred tax asset valuation allowance (1)	183		(92)		—		—		91
2023
Deferred tax asset valuation allowance (1)	200		(17)		—		—		183

__________

(1) Deducted from related assets.

Acquisitions (Details) - USD ($)
$ in Millions

1 Months Ended

2 Months Ended

3 Months Ended

5 Months Ended

11 Months Ended

12 Months Ended

Nov. 01, 2024

Aug. 01, 2024

Jan. 03, 2024

Nov. 30, 2023

Feb. 14, 2023

Dec. 31, 2023

Dec. 31, 2024

Jun. 30, 2025

Dec. 31, 2023

Dec. 31, 2024

Dec. 31, 2023

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Dec. 31, 2022

Business Combination [Line Items]

Payments to Acquire Businesses, Net of Cash Acquired

$ 1

$ 2,244

$ 1,568

Revenues

11,950

10,503

10,907

Gain on remeasurement of equity-method investments

127

Goodwill

$ 463

$ 466

$ 463

$ 466

$ 463

466

$ 466

463

Net income

2,618

2,225

3,179

Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

10,621

11,617

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

2,228

3,273

Transmission, Power & Gulf [Member]

Business Combination [Line Items]

Goodwill

400

West [Member]

Business Combination [Line Items]

Goodwill

$ 63

Crowheart Acquisition

Business Combination [Line Items]

Business Combination Achieved In Stages Preacquisition Working Interest In Acquiree Percentage

75.00%

Business Combination, Consideration Transferred

$ 307

Crowheart Acquisition | Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

^[1]

$ 74

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

^[1]

Crowheart Acquisition | Minimum [Member]

Business Combination [Line Items]

Business Combination Step Acquisition Working Interest In Acquiree After Acquisition Percentage

90.00%

Crowheart Acquisition | Other Operating Segment

Business Combination [Line Items]

Revenues

Modified EBITDA Earnings Loss

$ 7

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment

$ (56)

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities

$ (56)

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

$ 94

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

345

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

456

Business Combination, Recognized Liability Assumed, Other Liability, Current

(45)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(59)

Business Combination, Recognized Liability Assumed, Liability

(104)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

352

Crowheart Acquisition | Other Operating Segment | General and Administrative Expense

Business Combination [Line Items]

Business Combination Acquisition Related Costs Cumulative

Discovery Acquisition

Business Combination [Line Items]

Business Combination, Consideration Transferred

$ 170

Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Fair Value

381

Gain on remeasurement of equity-method investments

$ 127

127

Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Remeasurement, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration]

Other investing income (loss) - net

Discovery Acquisition | Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

^[1]

129

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

(5)

^[1]

$ (1)

Discovery Acquisition | Transmission, Power & Gulf [Member]

Business Combination [Line Items]

Revenues

144

Modified EBITDA Earnings Loss

$ 42

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

$ 22

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

941

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

1,021

Business Combination, Recognized Liability Assumed, Other Liability, Current

(40)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(296)

Business Combination, Recognized Liability Assumed, Liability

(336)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

$ 685

Discovery Acquisition | Transmission, Power & Gulf [Member] | Discovery Producer Services LLC [Member]

Business Combination [Line Items]

Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Percentage

60.00%

Business Combination, Voting Equity Interest Acquired, Percentage

40.00%

Discovery Acquisition | Transmission, Power & Gulf [Member] | General and Administrative Expense

Business Combination [Line Items]

Business Combination Acquisition Related Costs Cumulative

Gulf Coast Storage Acquisition

Business Combination [Line Items]

Business Combination, Consideration Transferred

$ 1,950

Business Combination, Voting Equity Interest Acquired, Percentage

100.00%

Business Combination, Consideration Transferred, Liabilities Incurred

$ 100

100

Gulf Coast Storage Acquisition | Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

$ 202

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

Gulf Coast Storage Acquisition | Transmission, Power & Gulf [Member]

Business Combination [Line Items]

Revenues

228

Modified EBITDA Earnings Loss

$ 160

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

2,035

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

2,101

Business Combination, Recognized Liability Assumed, Other Liability, Current

(11)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(107)

Business Combination, Recognized Liability Assumed, Liability

(118)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

$ 1,983

Gulf Coast Storage Acquisition | Transmission, Power & Gulf [Member] | General and Administrative Expense

Business Combination [Line Items]

Business Combination Acquisition Related Costs Cumulative

Business Combination, Acquisition-Related Cost, Expense

Cureton Acquisition

Business Combination [Line Items]

Business Combination, Consideration Transferred

$ 546

Business Combination, Voting Equity Interest Acquired, Percentage

100.00%

Acquired Finite-lived Intangible Assets, Weighted Average Useful Life

20 years

Percentage Of Finite Lived Intangible Assets Impacted By Our Intent Or Ability To Renew Or Extend Arrangement

24.00%

Acquired Finite-lived Intangible Asset, Weighted-Average Period before Renewal or Extension

10 years

Cureton Acquisition | West [Member]

Business Combination [Line Items]

Revenues

$ 35

Modified EBITDA Earnings Loss

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

$ 6

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

433

Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived

117

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

578

Business Combination, Recognized Liability Assumed, Other Liability, Current

(29)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(14)

Business Combination, Recognized Liability Assumed, Liability

(43)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

535

Goodwill

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill

546

Cureton Acquisition | West [Member] | General and Administrative Expense

Business Combination [Line Items]

Business Combination Acquisition Related Costs Cumulative

Business Combination, Acquisition-Related Cost, Expense

RMM Acquisition

Business Combination [Line Items]

Business Combination, Consideration Transferred

704

Extinguishment of Debt, Amount

$ 651

Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Fair Value

$ 406

Gain on remeasurement of equity-method investments

$ 30

$ 0

Acquired Finite-lived Intangible Assets, Weighted Average Useful Life

20 years

Percentage Of Finite Lived Intangible Assets Impacted By Our Intent Or Ability To Renew Or Extend Arrangement

18.00%

Acquired Finite-lived Intangible Asset, Weighted-Average Period before Renewal or Extension

10 years

RMM Acquisition | West [Member]

Business Combination [Line Items]

Revenues

Modified EBITDA Earnings Loss

$ 12

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

$ 28

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Investments

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

1,041

Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

1,168

Business Combination, Recognized Liability Assumed, Other Liability, Current

(44)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(103)

Business Combination, Recognized Liability Assumed, Liability

(147)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

1,021

Goodwill

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill

1,076

Business Combination, Goodwill, Expected Tax Deductible, Amount

$ 55

RMM Acquisition | West [Member] | Rocky Mountain Midstream Holdings LLC [Member]

Business Combination [Line Items]

Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Percentage

50.00%

Business Combination, Voting Equity Interest Acquired, Percentage

50.00%

DJ Basin Acquisitions | Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

^[1]

270

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

^[1]

MountainWest Acquisition

Business Combination [Line Items]

Business Combination, Consideration Transferred

$ 1,080

Business Combination, Voting Equity Interest Acquired, Percentage

100.00%

Business Combination, Consideration Transferred, Liabilities Incurred

$ 430

Payments to Acquire Businesses, Net of Cash Acquired

1,024

MountainWest Acquisition | Pro Forma [Member]

Business Combination [Line Items]

Business Combination, Pro Forma Information, Pro Forma Revenue

^[1]

Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax

^[1]

MountainWest Acquisition | Transmission, Power & Gulf [Member]

Business Combination [Line Items]

Revenues

$ 225

Modified EBITDA Earnings Loss

122

Business Combination, Transition Related Costs

$ 27

Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent

Business Combination, Recognized Asset Acquired, Receivable, Current

Business Combination, Recognized Asset Acquired, Other Asset, Current

Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Investments

Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment

1,019

Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent

Business Combination, Recognized Asset Acquired, Asset

1,154

Business Combination, Recognized Liability Assumed, Other Liability, Current

(47)

Business Combination, Recognized Liability Assumed, Long-Term Debt, Noncurrent

(365)

Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent

(95)

Business Combination, Recognized Liability Assumed, Liability

(507)

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)

647

Goodwill

400

Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill

1,047

Business Combination, Goodwill, Expected Tax Deductible, Amount

$ 400

MountainWest Acquisition | Transmission, Power & Gulf [Member] | General and Administrative Expense

Business Combination [Line Items]

Business Combination Acquisition Related Costs Cumulative

$ 18

Business Combination, Acquisition-Related Cost, Expense

$ 16

[1]	Excludes results from operations acquired in the acquisition for the period beginning on the acquisition date, as these results are included in the amounts as reported.

Consolidated Statement of Comprehensive Income (Loss) (Parenthetical) - Williams - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash flow hedging activities:
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax	$ (1)	$ (2)	$ (8)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	1	1	1
Pension and other postretirement benefits:
Other Comprehensive Income (Loss), Defined Benefit Plan, Net Actuarial Gain (Loss) Arising During Period, Tax	(9)	(24)	0
Other Comprehensive Income Loss, Reclassification Pension And Other Postretirement Benefit Plans Net Gain Loss Included In Net Periodic Benefit Cost (Credit), Tax	$ 2	$ 1	$ 0

Cash Payments For Interest (Net of Amounts Capitalized) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Williams Companies Inc [Member]
Debt Instrument [Line Items]
Cash payments for interest (net of amounts capitalized)	$ 1,404	$ 1,293	$ 1,152
Transcontinental Gas Pipe Line Company, LLC [Member]
Debt Instrument [Line Items]
Cash payments for interest (net of amounts capitalized)	336	302	307
Northwest Pipeline LLC [Member]
Debt Instrument [Line Items]
Cash payments for interest (net of amounts capitalized)	$ 24	$ 24	$ 26

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
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-Section 50
-Paragraph 8A
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section S50
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-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 7: http://www.xbrl.org/2003/role/exampleRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/exampleRef
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Reference 10: http://www.xbrl.org/2003/role/exampleRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Commodity Derivatives - Financial Statement Presentation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Current, Statement of Financial Position [Extensible Enumeration]	Derivative assets	Derivative assets
Derivative Liability, Current, Statement of Financial Position [Extensible Enumeration]	Derivative Liability, Current	Derivative Liability, Current
Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Liability	$ (386)	$ (382)
Derivative Liability, Fair Value, Gross Asset	575	670
Derivative Asset	336	344
Derivative Liability	(340)	(400)
Gain (Loss) on Derivative Instruments, Net, Pretax	119	(264)	$ 909
Energy Related Derivative \| Gain (Loss) on Derivative Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	120	(250)	956
Energy Related Derivative \| Cost of Sales
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(1)	(14)	(47)
Not Designated as Hedging Instrument [Member] \| Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Asset	722	726
Derivative Liability, Fair Value, Gross Liability	(915)	(1,070)
Not Designated as Hedging Instrument [Member] \| Energy Related Derivative \| Gain (Loss) on Derivative Instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Realized	(28)	111	253
Unrealized	148	(361)	703
Not Designated as Hedging Instrument [Member] \| Energy Related Derivative \| Cost of Sales
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Realized	(3)	(8)	(4)
Unrealized	2	(6)	$ (43)
Derivative assets [Member] \| Not Designated as Hedging Instrument [Member] \| Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Asset	494	508
Regulatory assets, deferred charges, and other [Member] \| Not Designated as Hedging Instrument [Member] \| Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Asset, Fair Value, Gross Asset	228	218
Derivative Liabilities [Member] \| Not Designated as Hedging Instrument [Member] \| Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Fair Value, Gross Liability	(535)	(635)
Regulatory liabilities, deferred income, and other [Member] \| Not Designated as Hedging Instrument [Member] \| Energy Related Derivative
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ (380)	$ (435)

Leases

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Leases [Text Block]

Note 14 – Leases

Williams, Transco, and NWP are lessees through noncancellable lease agreements for property and equipment consisting primarily of buildings, land, vehicles, and equipment used in both its operations and administrative functions.

Williams


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	39	$	39	$	38
Variable lease cost	33		31		31
Sublease income	—		—		(1)
Total lease cost	$	72	$	70	$	68
Cash paid for operating lease liabilities	$	40	$	37	$	37


	December 31,
	2025		2024
	(Dollars in Millions)
Other Information:
Right-of-use assets (included in Regulatory assets, deferred charges, and other)	$	170	$	154
Operating lease liabilities:
Current (included in Other current liabilities)	$	32	$	26
Noncurrent (included in Regulatory liabilities, deferred income, and other)	$	151	$	142
Weighted-average remaining lease term – operating leases (years)	10		11
Weighted-average discount rate – operating leases	4.99%		4.90%

At December 31, 2025, the following table represents operating lease maturities, including renewal provisions Williams has assessed as being reasonably certain of exercise, for each of the years ended December 31:


	(Millions)
2026	$	40
2027	36
2028	28
2029	25
2030	21
Thereafter	87
Total future lease payments	237
Less: Amount representing interest	54
Total obligations under operating leases	$	183

Williams is the lessor to certain lease agreements for office space in its headquarters building, which are insignificant to its financial statements.

Transco


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	11	$	9	$	9
Variable lease cost	7		7		7
Total lease cost	$	18	$	16	$	16
Cash paid for operating lease liabilities	$	12	$	9	$	10

			December 31,
			2025		2024
			(Dollars in Millions)
Other Information:
Right-of-use assets (included in Deferred charges and other in Transco’s Balance Sheet)			$	64	$	48
Operating lease liabilities:
Current (included in Other current liabilities in Transco’s Balance Sheet)			$	9	$	6
Noncurrent (included in Deferred income and other in Transco’s Balance Sheet)			$	63	$	51
Weighted-average remaining lease term – operating leases (years)			12		13
Weighted-average discount rate – operating leases			4.84%		4.77%

As of December 31, 2025, the following table represents operating lease maturities, including renewal provisions that Transco has assessed as being reasonably certain of exercise, for each of the years ended December 31:


	(Millions)
2026	$	12
2027	13
2028	12
2029	13
2030	12
Thereafter	36
Total future lease payments	98
Less: Amount representing interest	26
Total obligations under operating leases	$	72

NWP


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	1	$	3		$	1
Variable lease cost	—		1			1
Total lease cost	$	1	$	4		$	2
Cash paid for operating lease liabilities	$	1	$	2		$	1

			December 31,
			2025			2024
			(Dollars in Millions)
Other Information:
Right-of-use assets (included in Deferred charges and other in NWP’s Balance Sheet)			$	4		$	5
Operating lease liabilities:
Current (included in Other current liabilities in NWP’s Balance Sheet)			$	—		$	1
Noncurrent (included in Deferred income and other in NWP’s Balance Sheet)			$	4		$	5
Weighted-average remaining lease term – operating leases (years)			18			19
Weighted-average discount rate – operating leases			4.66%			4.90%

As of December 31, 2025, the following table represents operating lease maturities, including renewal provisions that NWP has assessed as being reasonably certain of exercise, for each of the years ended December 31:


	(Millions)
2026	$	—
2027	1
2028	—
2029	1
2030	—
Thereafter	4
Total future lease payments	6
Less: Amount representing interest	2
Total obligations under operating leases	$	4

Fair Value Measurements - ARO Trust (Details) - Transcontinental Gas Pipe Line Company, LLC [Member] - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	$ 223	$ 200
Debt Securities, Trading, and Equity Securities, FV-NI	356	297
External Trust
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transco's annual funding commitment for ARO	51
Cash management funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	34	27
Debt Securities, Trading, and Equity Securities, FV-NI	34	27
Private Equity Funds, US
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	53	53
Debt Securities, Trading, and Equity Securities, FV-NI	169	146
Private Equity Funds, Non-US
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	32	32
Debt Securities, Trading, and Equity Securities, FV-NI	51	40
Municipal Bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	104	88
Debt Securities, Trading, and Equity Securities, FV-NI	$ 102	$ 84

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2025
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Long-Term Debt Maturities (Details) $ in Millions	Dec. 31, 2025 USD ($)
Debt Instrument [Line Items]
2026	$ 1,345
2027	1,994
2028	1,696
2029	1,600
2030	2,504
Transcontinental Gas Pipe Line Company, LLC [Member]
Debt Instrument [Line Items]
2026	246
2027	42
2028	446
2029	50
2030	754
Northwest Pipeline LLC [Member]
Debt Instrument [Line Items]
2027	500
2028	$ 250

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

EBP Asset rollforward and B.S. classification (Details 1) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Amounts included in regulatory liabilities associated with Transco and Northwest Pipeline:
Net regulatory liabilities	$ 99	$ 139
Pension Benefits [Member]
Change in plan assets:
Fair value of plan assets at beginning of year	1,183	1,167
Actual return on plan assets	123	88
Employer contributions	5	4
Plan participants’ contributions	0	0
Benefits paid	(89)	(73)
Settlements	(5)	(3)
Net increase (decrease) in fair value of plan assets	34	16
Fair value of plan assets at end of year	1,217	1,183
Funded status — overfunded (underfunded)	268	246
Amounts recognized in the Consolidated Balance Sheet:
Noncurrent assets	290	270
Current liabilities	(3)	(4)
Noncurrent liabilities	(19)	(20)
Funded status - overfunded (underfunded)	268	246
Accumulated benefit obligation	942	929
Plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	22	23
Plans with an accumulated benefit obligation in excess of plan assets:
Accumulated benefit obligation	20	22
Fair value of plan assets	0	0
Amounts recognized in Accumulated other comprehensive income (loss):
Net actuarial gain (loss)	78	49
Other Postretirement Benefits [Member]
Change in plan assets:
Fair value of plan assets at beginning of year	272	262
Actual return on plan assets	21	16
Employer contributions	4	3
Plan participants’ contributions	1	2
Benefits paid	(12)	(11)
Settlements	0	0
Net increase (decrease) in fair value of plan assets	14	10
Fair value of plan assets at end of year	286	272
Funded status — overfunded (underfunded)	158	140
Amounts recognized in the Consolidated Balance Sheet:
Noncurrent assets	161	143
Current liabilities	(3)	(3)
Noncurrent liabilities	0	0
Funded status - overfunded (underfunded)	158	140
Amounts recognized in Accumulated other comprehensive income (loss):
Net actuarial gain (loss)	$ 57	$ 20

Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2025

Revenue Recognition [Abstract]

Disaggregation of Revenue [Table Text Block]

The following tables present Williams’ revenue disaggregated by major service line:


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services		Other		Eliminations		Total
	(Millions)






























2025
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,804	$	—	$	—	$	—	$	—	$	(83)	$	3,721
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	933		1,850		1,824		—		—		(235)		4,372
Commodity consideration	104		2		86		—		—		—		192
Other	51		99		24		—		1		(20)		155
Total service revenues	4,892		1,951		1,934		—		1		(338)		8,440
Product sales	512		171		906		6,047		580		(1,757)		6,459
Total revenues from contracts with customers	5,404		2,122		2,840		6,047		581		(2,095)		14,899
Other revenues (1)	39		46		7		3,303		61		(2)		3,454
Other adjustments (2)	—		—		—		(7,175)		—		772		(6,403)
Total revenues	$	5,443	$	2,168	$	2,847	$	2,175	$	642	$	(1,325)	$	11,950

2024
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,500	$	—	$	—	$	—	$	—	$	(81)	$	3,419
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	661		1,778		1,693		—		—		(162)		3,970
Commodity consideration	54		2		78		—		—		—		134
Other	46		92		21		—		—		(19)		140
Total service revenues	4,261		1,872		1,792		—		—		(262)		7,663
Product sales	328		110		869		4,530		420		(1,288)		4,969
Total revenues from contracts with customers	4,589		1,982		2,661		4,530		420		(1,550)		12,632
Other revenues (1)	39		43		8		2,236		24		(2)		2,348
Other adjustments (2)	—		—		—		(4,977)		—		500		(4,477)
Total revenues	$	4,628	$	2,025	$	2,669	$	1,789	$	444	$	(1,052)	$	10,503


	Transmission, Power & Gulf		Northeast G&P		West		Gas & NGL Marketing Services		Other		Eliminations		Total
	(Millions)
2023
Revenues from contracts with customers:
Service revenues:
Regulated interstate natural gas transportation and storage	$	3,334	$	—	$	—	$	—	$	—	$	(60)	$	3,274
Gathering, processing, transportation, fractionation, and storage:
Monetary consideration	443		1,782		1,478		—		—		(170)		3,533
Commodity consideration	38		5		103		—		—		—		146
Other	30		87		12		1		—		(15)		115
Total service revenues	3,845		1,874		1,593		1		—		(245)		7,068
Product sales	252		132		441		4,615		442		(954)		4,928
Total revenues from contracts with customers	4,097		2,006		2,034		4,616		442		(1,199)		11,996
Other revenues (1)	53		27		101		4,294		64		(2)		4,537
Other adjustments (2)	—		—		—		(6,032)		—		406		(5,626)
Total revenues	$	4,150	$	2,033	$	2,135	$	2,878	$	506	$	(795)	$	10,907

______________

Contract with Customer, Asset and Liability [Table Text Block]

The following table presents a reconciliation of contract assets:













	Year Ended December 31,
	Williams				Transco				NWP
	2025		2024		2025		2024		2025		2024
	(Millions)
Balance at beginning of year	$	98	$	36	$	10	$	—	$	21	$	17
Revenue recognized in excess of amounts invoiced	86		170		5		10		6		6
Contract assets acquired	—		36		—		—		—		—
Minimum volume commitments invoiced	(58)		(144)		—		—		—		—
Amortization of contract assets	(17)		—		(2)		—		(3)		(2)
Balance at end of year	$	109	$	98	$	13	$	10	$	24	$	21

Contract Liabilities

The following table presents a reconciliation of contract liabilities:














	Year Ended December 31,
	Williams				Transco				NWP
	2025		2024		2025		2024		2025		2024
	(Millions)
Balance at beginning of year	$	1,046	$	1,081	$	173	$	184	$	—	$	2
Payments received and deferred	198		183		—		—		—		—
Liabilities acquired and other additions	23		53		—		—		—		—
Significant financing component	7		8		—		—		—		—
Liabilities reclassified as held for sale	(19)		—		—		—		—		—
Recognized in revenue	(307)		(279)		(10)		(11)		—		(2)
Balance at end of year	$	948	$	1,046	$	163	$	173	$	—	$	—

Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]


	Contract Liabilities
	Williams		Transco		NWP
	(Millions)
2026 (one year)	$	169	$	10	$	—
2027 (one year)	145		10		—
2028 (one year)	120		11		—
2029 (one year)	91		11		—
2030 (one year)	68		10		—
Thereafter	355		111		—
Total	$	948	$	163	$	—


	Remaining Performance Obligations
	Williams		Transco		NWP
	(Millions)
2026 (one year)	$	4,589	$	2,990	$	399
2027 (one year)	4,265		2,772		386
2028 (one year)	3,865		2,576		367
2029 (one year)	2,970		1,846		348
2030 (one year)	2,703		1,759		342
Thereafter	13,779		9,990		1,919
Total	$	32,171	$	21,933	$	3,761

Contingencies and Commitments (Details) $ in Millions	1 Months Ended	12 Months Ended
Contingencies and Commitments (Details) $ in Millions	Feb. 28, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		$ 42
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]		Other Liabilities and Deferred Revenue, Noncurrent, Other current liabilities
Other current liabilities		$ 1,639	$ 1,360
Unrecorded Unconditional Purchase Obligation Percent Of Production		0.10
Transcontinental Gas Pipe Line Company, LLC [Member]
Loss Contingencies [Line Items]
Regulatory Assets, Current		$ 126	74
Other current liabilities		143	105
Interest Income, Other		37	58	$ 87
Transcontinental Gas Pipe Line Company, LLC [Member] \| Environmental Restoration Costs
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		$ 10
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]		Other current liabilities, Other Liabilities, Noncurrent
Transcontinental Gas Pipe Line Company, LLC [Member] \| Potentially Responsible Party At Various Superfund And State Waste Disposal Sites \| Maximum [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies, Gross		$ 1
Northwest Pipeline LLC [Member]
Loss Contingencies [Line Items]
Regulatory Assets, Current		3	6
Other current liabilities		32	34
Northwest Pipeline LLC [Member] \| Environmental Restoration Costs
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		$ 1
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]		Other current liabilities, Other Liabilities, Noncurrent
Northwest Pipeline LLC [Member] \| Washington State Climate Commitment Act
Loss Contingencies [Line Items]
Regulatory Assets, Current		$ 72	38
Other current liabilities		6	3
Interest Income, Other		4	2
Capital Addition Purchase Commitments [Member]
Loss Contingencies [Line Items]
Commitments for construction and acquisition of property, plant, and equipment		4,300
Capital Addition Purchase Commitments [Member] \| Transcontinental Gas Pipe Line Company, LLC [Member]
Loss Contingencies [Line Items]
Commitments for construction and acquisition of property, plant, and equipment		414
Capital Addition Purchase Commitments [Member] \| Northwest Pipeline LLC [Member]
Loss Contingencies [Line Items]
Commitments for construction and acquisition of property, plant, and equipment		57
Gas & NGL Marketing Services
Loss Contingencies [Line Items]
Other Commitment		974
Payments to Suppliers		301	$ 293	$ 244
Gas Pipeline [Member]
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		11
Unrecorded Estimated Recoveries For Environmental Loss Contingencies		3
Natural Gas Underground Storage Facilities [Member]
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		9
Former Operations [Member]
Loss Contingencies [Line Items]
Accrued environmental loss liabilities		$ 22
Construction Project \| Transcontinental Gas Pipe Line Company, LLC [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount Awarded to Other Party	$ 110
Loss Contingency Expected Recovery Percentage	29.00%

Provision (Benefit) for Income Taxes Tax Provison (Benefit) Table (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Current :
Federal	$ 99	$ 125	$ 3
State	14	9	21
Total	113	134	24
Deferred:
Federal	597	472	872
State	147	34	109
Total	744	506	981
Less: Provision (benefit) for income taxes	$ 857	$ 640	$ 1,005

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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+ Details

Consolidated Statement of Changes in Equity - Williams - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Capital in Excess of Par Value	Retained Deficit	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total Stockholders' Equity	Noncontrolling Interests
Beginning balance at Dec. 31, 2022	$ 14,045	$ 35	$ 1,253	$ 24,542	$ (13,271)	$ (24)	$ (1,050)	$ 11,485	$ 2,560
Net income (loss)	3,303	0	0	0	3,179	0	0	3,179	124
Other comprehensive income (loss)	25	0	0	0	0	25	0	25	0
Dividends, Common Stock, Cash	(2,179)	0	0	0	(2,179)	0	0	(2,179)	0
Stock-based compensation and related common stock issuances, net of tax	38	0	3	35	0	0	0	38	0
Dividends and distributions to noncontrolling interests	(213)	0	0	0	0	0	0	0	(213)
Contributions from noncontrolling interests	18	0	0	0	0	0	0	0	18
Purchases of treasury stock	(130)	0	0	0	0	0	(130)	(130)	0
Other	(16)	0	0	1	(16)	(1)	0	(16)	0
Net increase (decrease) in equity	846	0	3	36	984	24	(130)	917	(71)
Ending balance at Dec. 31, 2023	14,891	35	1,256	24,578	(12,287)	0	(1,180)	12,402	2,489
Net income (loss)	2,346	0	0	0	2,225	0	0	2,225	121
Other comprehensive income (loss)	76	0	0	0	0	76	0	76	0
Dividends, Common Stock, Cash	(2,316)	0	0	0	(2,316)	0	0	(2,316)	0
Stock-based compensation and related common stock issuances, net of tax	67	0	2	65	0	0	0	67	0
Dividends and distributions to noncontrolling interests	(242)	0	0	0	0	0	0	0	(242)
Contributions from noncontrolling interests	36	0	0	0	0	0	0	0	36
Purchases of treasury stock	0
Other	(18)	0	0	0	(18)	0	0	(18)	0
Net increase (decrease) in equity	(51)	0	2	65	(109)	76	0	34	(85)
Ending balance at Dec. 31, 2024	14,840	35	1,258	24,643	(12,396)	76	(1,180)	12,436	2,404
Net income (loss)	2,768	0	0	0	2,618	0	0	2,618	150
Other comprehensive income (loss)	22	0	0	0	0	22	0	22	0
Dividends, Common Stock, Cash	(2,442)	0	0	0	(2,442)	0	0	(2,442)	0
Stock-based compensation and related common stock issuances, net of tax	35	0	3	32	0	0	0	35	0
Dividends and distributions to noncontrolling interests	(259)	0	0	0	0	0	0	0	(259)
Noncontrolling interest resulting from acquisition	25	0	0	0	0	0	0	0	25
Changes in ownership of consolidated subsidiaries, net (Note 2)	(40)	0	0	126	0	0	0	126	(166)
Contributions from noncontrolling interests	36	0	0	0	0	0	0	0	36
Purchases of treasury stock	0
Other	10	0	0	0	(17)	29	0	12	(2)
Net increase (decrease) in equity	155	0	3	158	159	51	0	371	(216)
Ending balance at Dec. 31, 2025	$ 14,995	$ 35	$ 1,261	$ 24,801	$ (12,237)	$ 127	$ (1,180)	$ 12,807	$ 2,188

Goodwill and Other Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill [Table Text Block]

Changes in the carrying amount of goodwill, included in Intangible assets – net in Williams’ Consolidated Balance Sheet, by reportable segment for the years indicated are as follows:


	Transmission, Power & Gulf		West		Total
	(Millions)
December 31, 2023	$	400	$	63	$	463
Cureton Acquisition (Note 3)	—		5		5
RMM Acquisition (Note 3)	—		(2)		(2)
December 31, 2024	400		66		466
December 31, 2025	$	400	$	66	$	466

Schedule of Finite-Lived Intangible Assets [Table Text Block]

The gross carrying amount and accumulated amortization of other intangible assets, included in Intangible assets – net in Williams’ Consolidated Balance Sheet, at December 31 are as follows:


	2025				2024
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
	(Millions)
Customer relationships	$	10,113	$	(3,832)	$	10,239	$	(3,523)
Transportation and storage capacity contracts	267		(254)		267		(244)
Other	6		(3)		6		(2)
Other intangible assets	$	10,386	$	(4,089)	$	10,512	$	(3,769)

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

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+ Details

Statement of Cash Flows - NWP - USD ($) $ in Millions	12 Months Ended
Statement of Cash Flows - NWP - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
Net income	$ 2,768	$ 2,346	$ 3,303
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Depreciation, depletion, and amortization	2,347	2,219	2,071
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Increase (Decrease) in Inventories	(45)	(9)	13
Increase (Decrease) in Other Current Assets	(71)	9	60
Other current liabilities	170	35	(19)
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item	(213)	(245)	(226)
Net cash provided (used) by operating activities	5,898	4,974	5,938
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
Proceeds from Issuance of Long-term Debt	4,940	3,594	2,755
Repayments of Long-term Debt	(2,827)	(2,946)	(634)
Net cash provided (used) by financing activities	(406)	(2,201)	(49)
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
Capital expenditures (1)	(4,893)	(2,573)	(2,516)
Net cash provided (used) by investing activities	(5,489)	(4,863)	(3,891)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	3	(2,090)	1,998
Cash and cash equivalents at beginning of year	60	2,150	152
Cash and cash equivalents at end of year	63	60	2,150
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Property, Plant and Equipment, Additions	(5,375)	(2,581)	(2,564)
Capital expenditures	(4,893)	(2,573)	(2,516)
Northwest Pipeline LLC [Member]
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
Net income	181	180	180
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Depreciation, depletion, and amortization	117	111	111
Increase (Decrease) in Allowance for Equity Funds Used During Construction	(7)	(8)	(3)
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Increase (Decrease) in Accounts Receivable, Related Parties	0	1	0
Increase (Decrease) in Accounts and Other Receivables	(1)	(1)	0
Increase (Decrease) in Inventories	0	(1)	1
Increase (Decrease) in Other Current Assets	(2)	(2)	1
Increase (Decrease) in Accounts Payable, Trade	(1)	(3)	4
Increase (Decrease) in Accounts Payable, Related Parties	0	(1)	1
IncreaseDecreaseInOtherRegulatoryLiabilities	0	1	(126)
Other current liabilities	3	(3)	3
Increase (Decrease) in Regulatory Assets Noncurrent	(31)	(15)	(29)
Increase (Decrease) in Regulatory Liabilities Noncurrent	(21)	(27)	(20)
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item	7	7	6
Net cash provided (used) by operating activities	245	239	129
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
Proceeds from Issuance of Long-term Debt	250	0	0
Repayments of Long-term Debt	(85)	0	0
Cash distributions to parent	(148)	(150)	(155)
Cash contributions from parent	231	0	0
Increase Decrease In Advances From Affiliates	(26)	26	0
Net cash provided (used) by financing activities	222	(124)	(155)
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
Capital expenditures (1)	(234)	(266)	(125)
Contributions in aid of construction	7	5	6
Payments for (Proceeds from) Removal Costs	(22)	(12)	(8)
IncreaseDecreaseInAdvancesToAffiliates	(218)	158	153
Net cash provided (used) by investing activities	(467)	(115)	26
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Property, Plant and Equipment, Additions	(223)	(266)	(140)
Increase (Decrease) in Accounts Payable And Accrued Liabilities Related To Capital Expenditures	(11)	0	15
Capital expenditures	$ (234)	$ (266)	$ (125)

Consolidated Statement of Comprehensive Income (Loss) - Williams - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Comprehensive income (loss):
Net income (loss)	$ 2,768	$ 2,346	$ 3,303
Designated interest rate cash flow hedging activities:
Net unrealized gain (loss) from derivative instruments, net of taxes of $(1), $(2), and $(8) in 2025, 2024, and 2023, respectively	3	6	26
Reclassifications into earnings of net derivative instruments (gain) loss, net of taxes of $1, $1, and $1 in 2025, 2024, and 2023, respectively	(3)	(2)	(2)
Pension and other postretirement benefits:
Net actuarial gain (loss) arising during the year, net of taxes of $(9), $(24), and $— in 2025, 2024, and 2023, respectively	27	72	(2)
Amortization of actuarial (gain) loss and net actuarial loss from settlements included in net periodic benefit cost (credit), net of taxes of $2, $1, and $— in 2025, 2024, and 2023, respectively	(5)	0	3
Other comprehensive income (loss)	22	76	25
Comprehensive income (loss)	2,790	2,422	3,328
Less: Comprehensive income (loss) attributable to noncontrolling interests	150	121	124
Comprehensive income (loss) attributable to The Williams Companies, Inc.	$ 2,640	$ 2,301	$ 3,204

Commodity Derivatives

12 Months Ended

Dec. 31, 2025

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Commodity Derivatives [Text Block]

Note 17 – Commodity Derivatives

Williams is exposed to commodity price risk and utilizes derivatives to manage a portion of that risk. Williams reports the fair value of commodity derivatives in Derivative assets; Regulatory assets, deferred charges, and other; Derivative liabilities; or Regulatory liabilities, deferred income, and other. The asset and liability derivative positions are netted by counterparty as permitted under the terms of the master netting arrangements and are also presented net of cash held on deposit in margin accounts that Williams has received or remitted to collateralize certain derivative positions. See Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk for additional fair value information. In Williams’ Consolidated Statement of Cash Flows, any cash impacts of settled commodity derivatives are recorded as operating activities.

Williams experiences significant earnings volatility from the fair value accounting required for the derivatives used to hedge a portion of the economic value of the underlying transportation and storage capacity portfolios as well as upstream-related production. However, the unrealized fair value measurement gains and losses on the derivatives are generally offset by valuation changes in the economic value of the underlying production or transportation and storage capacity contracts, which are not recognized until the underlying transaction occurs.

Volumes

At December 31, 2025, the notional volume of the net long (short) positions for Williams’ commodity derivative contracts were as follows:

Commodity

Unit of Measure

Net Long (Short) Position

Index Risk

Natural Gas

MMBtu

1,110,264,783

Central Hub Risk - Henry Hub

Natural Gas

MMBtu

(10,941,340)

Basis Risk

Natural Gas

MMBtu

502,600,784

Central Hub Risk - Mont Belvieu

Natural Gas Liquids

Barrels

(456,000)

Basis Risk

Natural Gas Liquids

Barrels

50,000

Financial Statement Presentation

The fair value of commodity derivatives, which are not designated as hedging instruments for accounting purposes, is reflected as follows:


	December 31, 2025				December 31, 2024
Commodity Derivatives Categories	Assets		(Liabilities)		Assets		(Liabilities)
	(Millions)





Current	$	494	$	(535)	$	508	$	(635)
Noncurrent	228		(380)		218		(435)
Total commodity derivatives	722		(915)		726		(1,070)
Counterparty and collateral netting offset	(386)		575		(382)		670
Amounts recognized in Williams’ Consolidated Balance Sheet	$	336	$	(340)	$	344	$	(400)

The pre-tax impacts of Williams’ commodity derivatives, which are not designated as hedging instruments for accounting purposes, are reflected as follows:


	Year Ended December 31,

	2025		2024		2023
	(Millions)
Net gain (loss) from commodity derivatives within Total revenues:

Realized	$	(28)	$	111	$	253
Unrealized	148		(361)		703
	$	120	$	(250)	$	956

Net gain (loss) from commodity derivatives within Net processing commodity expenses:
Realized	$	(3)	$	(8)	$	(4)
Unrealized	2		(6)		(43)
	$	(1)	$	(14)	$	(47)
Total net gain (loss) from commodity derivatives	$	119	$	(264)	$	909

Contingent Features

Generally, collateral may be provided in the form of a parent guaranty, letter of credit, or cash. If collateral is required, fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral are offset against fair value amounts recognized for derivatives executed with the same counterparty.

Williams has specific trade and credit contracts that contain minimum credit rating requirements. These credit rating requirements typically give counterparties the right to suspend or terminate credit if Williams’ credit ratings are downgraded to non-investment grade status. Under such circumstances, Williams would need to post collateral to continue transacting business with these counterparties. At December 31, 2025, the contractually required collateral in the event of a credit rating downgrade to non-investment grade status was $30 million.

Williams maintains accounts with brokers or the clearing houses of certain exchanges to facilitate financial derivative transactions. Based on the value of the positions in these accounts and the associated margin requirements, Williams may be required to deposit cash into these accounts. At December 31, 2025 and 2024, net cash collateral held on deposit in broker margin accounts was $189 million and $288 million, respectively.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

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+ Details

Statement of Cash Flows - Transco - USD ($) $ in Millions	12 Months Ended
Statement of Cash Flows - Transco - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
Net income	$ 2,768	$ 2,346	$ 3,303
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Depreciation, depletion, and amortization	2,347	2,219	2,071
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Increase (Decrease) in Inventories	(45)	(9)	13
Increase (Decrease) in Other Current Assets	(71)	9	60
Other current liabilities	170	35	(19)
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item	(213)	(245)	(226)
Net cash provided (used) by operating activities	5,898	4,974	5,938
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
Proceeds from Issuance of Long-term Debt	4,940	3,594	2,755
Repayments of Long-term Debt	(2,827)	(2,946)	(634)
Payments for debt issuance costs	(45)	(32)	(23)
Net cash provided (used) by financing activities	(406)	(2,201)	(49)
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
Capital expenditures (1)	(4,893)	(2,573)	(2,516)
Net cash provided (used) by investing activities	(5,489)	(4,863)	(3,891)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	3	(2,090)	1,998
Cash and cash equivalents at beginning of year	60	2,150	152
Cash and cash equivalents at end of year	63	60	2,150
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Property, Plant and Equipment, Additions	(5,375)	(2,581)	(2,564)
Capital expenditures	(4,893)	(2,573)	(2,516)
Transcontinental Gas Pipe Line Company, LLC [Member]
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
Net income	1,426	1,313	1,247
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Depreciation, depletion, and amortization	574	545	519
Increase (Decrease) in Allowance for Equity Funds Used During Construction	(28)	(71)	(63)
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Increase (Decrease) in Accounts Receivable, Related Parties	17	(14)	(1)
Increase (Decrease) in Accounts and Other Receivables	(67)	0	6
Increase (Decrease) in Inventories	(1)	2	10
Increase (Decrease) in Other Regulatory Assets	(52)	13	37
Increase (Decrease) in Other Current Assets	0	(10)	27
Increase (Decrease) in Accounts Payable, Trade	14	(4)	(18)
Increase (Decrease) in Accounts Payable, Related Parties	7	0	1
Increase (Decrease) In Reserve For Rate Refunds	179	0	0
Other current liabilities	49	(63)	72
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Other Item	(43)	(15)	(122)
Net cash provided (used) by operating activities	2,075	1,696	1,715
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
Proceeds from Issuance of Long-term Debt	1,696	0	0
Proceeds from Issuance of Other Long-Term Debt	3	2	7
Repayments of Long-term Debt	(1,000)	0	0
Repayments of Other Long-Term Debt	(35)	(32)	(29)
Payments for debt issuance costs	(15)	0	0
Cash distributions to parent	(1,340)	(1,145)	(1,220)
Net cash provided (used) by financing activities	(691)	(1,175)	(1,242)
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
Capital expenditures (1)	(965)	(1,140)	(894)
Contributions in aid of construction	28	16	21
Payments for (Proceeds from) Removal Costs	(107)	(110)	(51)
IncreaseDecreaseInAdvancesToAffiliates	(316)	715	460
Payments to Acquire Investments to be Held in Decommissioning Trust Fund	(64)	(23)	(22)
Proceeds from Decommissioning Trust Fund Assets	40	21	13
Net cash provided (used) by investing activities	(1,384)	(521)	(473)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	0	0	0
Cash and cash equivalents at beginning of year	0	0	0
Cash and cash equivalents at end of year	0	0	0
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Property, Plant and Equipment, Additions	(918)	(1,112)	(991)
Increase (Decrease) in Accounts Payable And Accrued Liabilities Related To Capital Expenditures	(47)	(28)	97
Capital expenditures	$ (965)	$ (1,140)	$ (894)

Statement of Changes in Member's Equity - NWP - USD ($) $ in Millions	Total	Northwest Pipeline LLC [Member]	Member's Capital Northwest Pipeline LLC [Member]	Retained Earnings Northwest Pipeline LLC [Member]
Balance at beginning of period at Dec. 31, 2022			$ 1,074	$ 34
Capital contributions from parent		$ 0	0
Net income	$ 3,179			180
Cash distributions to parent		155		(155)
Balance at end of period at Dec. 31, 2023		1,133	1,074	59
Capital contributions from parent		0	0
Net income	2,225			180
Cash distributions to parent		150		(150)
Balance at end of period at Dec. 31, 2024		1,163	1,074	89
Capital contributions from parent		(231)	231
Net income	$ 2,618			181
Cash distributions to parent		148		(148)
Balance at end of period at Dec. 31, 2025		$ 1,427	$ 1,305	$ 122

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Other Current Liabilities

12 Months Ended

Dec. 31, 2025

Accrued Liabilities, Current [Abstract]

Other Current Liabilities [Text Block]

Note 12 – Other Current Liabilities

Williams


	December 31,
	2025		2024
	(Millions)
Interest on debt	$	342	$	350
Employee costs	283		285
Reserve for rate refunds (Note 18)	179		—
Contract liabilities (Note 5)	165		170

Regulatory liabilities (Note 10)	117		85
Asset retirement obligations (Note 9)	103		91
Operating lease liabilities (Note 14)	32		26

Other, including accrued loss contingencies	418		353
	$	1,639	$	1,360

Transco


	December 31,
	2025		2024
	(Millions)

Customer deposits	$	68	$	45
Taxes, other than income taxes	28		27
Contract liabilities	11		10
Other	36		23

	$	143	$	105

NWP


	December 31,
	2025		2024
	(Millions)
Taxes, other than income taxes	$	9	$	8
Interest on debt	6		6
Transportation and gas exchange payables	5		10
Other	12		10

	$	32	$	34

EBP Key Assumptions (Details 3)	12 Months Ended
EBP Key Assumptions (Details 3)	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits [Member]
Weighted average assumptions utilized to determine benefit obligations
Discount rate	5.32%	5.60%	4.98%
Rate of compensation increase	3.48%	3.48%	3.52%
Cash balance interest crediting rate	4.25%	4.00%	4.50%
Weighted average assumptions utilized to determine net periodic benefit cost (credit)
Discount rate	5.60%	4.98%	5.16%
Expected long-term rate of return on plan assets	5.35%	5.31%	5.17%
Rate of compensation increase	3.48%	3.52%	3.58%
Cash balance interest crediting rate	4.00%	4.50%	3.50%
Other Postretirement Benefits [Member]
Weighted average assumptions utilized to determine benefit obligations
Discount rate	5.47%	5.67%	5.01%
Weighted average assumptions utilized to determine net periodic benefit cost (credit)
Discount rate	5.67%	5.01%	5.20%
Expected long-term rate of return on plan assets	4.20%	4.16%	4.04%
Health care cost trend rate assumed for next fiscal year	9.10%
Direction and pattern of change for assumed health care cost trend rate	decreases
Ultimate health care cost trend rate	4.50%
Year that rate reaches ultimate trend rate	2035

Employee Benefit Plans

12 Months Ended

Dec. 31, 2025

Retirement Benefits [Abstract]

Employee Benefit Plans [Text Block]

Note 7 – Employee Benefit Plans

Pension Plans

Williams has noncontributory defined benefit pension plans for eligible employees hired prior to January 1, 2019. Eligible employees earn compensation credits based on a cash balance formula. As of January 1, 2020, certain active employees are no longer eligible to receive compensation credits.

Other Postretirement Benefits [Member]

Components of net periodic benefit cost (credit):

Service cost

Interest cost

Expected return on plan assets

(11)

(10)

Amortization of net actuarial loss (gain)

(9)

(5)

(3)

Net actuarial loss from settlements

Reclassification to regulatory liability

Net periodic benefit cost (credit) (1)

^[1]

(11)

(8)

(5)

Items Recognized in Other Comprehensive Income (Loss)

Net actuarial gain (loss) arising during the year

Amortization of net actuarial loss (gain)

(8)

(2)

Net actuarial loss from settlements

Total recognized in Other comprehensive income (loss)

$ 0

$ 1

[1]	Components other than Service cost are included in Other income (expense) – net below Operating income (loss) in Williams’ Consolidated Statement of Income.

Subsequent Event (Details) - $ / shares		12 Months Ended
Subsequent Event (Details) - $ / shares	Jan. 27, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared		$ 2.00	$ 1.90	$ 1.79
Subsequent Event [Member]
Subsequent Event [Line Items]
Common Stock, Dividends, Per Share, Declared	$ 0.525

Fair Value Measurements Nonrecurring Measurements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair Value Assets Measured On Nonrecurring Basis [Abstract]
Other Asset Impairment Charges	$ 212	$ 0	$ 10
Williams Companies Inc [Member] \| Level 2 [Member] \| West [Member] \| Fair Value, Nonrecurring [Member]
Fair Value Assets Measured On Nonrecurring Basis [Abstract]
Long-Lived Asset, Held-for-Sale, Fair Value Disclosure	48
Williams Companies Inc [Member] \| Impairment or write-off of certain assets [Member] \| Level 3 [Member] \| West [Member] \| Property, plant, and equipment, net [Member]
Fair Value Assets Measured On Nonrecurring Basis [Abstract]
Impairment of certain assets	25
Williams Companies Inc [Member] \| Impairment or write-off of certain assets [Member] \| Level 2 [Member] \| West [Member]
Fair Value Assets Measured On Nonrecurring Basis [Abstract]
Impairment of Long-Lived Assets to be Disposed of	$ 176

Goodwill and Other Intangible Assets

12 Months Ended

Dec. 31, 2025

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Other Intangible Assets [Text Block]

Note 11 – Goodwill and Other Intangible Assets

Goodwill

Changes in the carrying amount of goodwill, included in Intangible assets – net in Williams’ Consolidated Balance Sheet, by reportable segment for the years indicated are as follows:


	Transmission, Power & Gulf		West		Total
	(Millions)
December 31, 2023	$	400	$	63	$	463
Cureton Acquisition (Note 3)	—		5		5
RMM Acquisition (Note 3)	—		(2)		(2)
December 31, 2024	400		66		466
December 31, 2025	$	400	$	66	$	466

Goodwill is not subject to amortization, but is evaluated at least annually for impairment or more frequently if impairment indicators are present. Williams did not identify or recognize any impairments to goodwill in connection with the evaluation of goodwill for impairment during the year ended December 31, 2025.

Other Intangible Assets

The gross carrying amount and accumulated amortization of other intangible assets, included in Intangible assets – net in Williams’ Consolidated Balance Sheet, at December 31 are as follows:


	2025				2024
	Gross Carrying Amount		Accumulated Amortization		Gross Carrying Amount		Accumulated Amortization
	(Millions)
Customer relationships	$	10,113	$	(3,832)	$	10,239	$	(3,523)
Transportation and storage capacity contracts	267		(254)		267		(244)
Other	6		(3)		6		(2)
Other intangible assets	$	10,386	$	(4,089)	$	10,512	$	(3,769)

Customer Relationships

Customer relationships primarily relate to gas gathering, processing, and fractionation contractual customer relationships recognized in acquisitions. Contractual customer relationships are being amortized on a straight-line basis over the term for which the contractual customer relationships are expected to contribute to cash flows.

Williams expenses costs incurred to renew or extend the terms of its gas gathering, processing, and fractionation contracts with customers. Although a significant portion of the expected future cash flows associated with these contractual customer relationships are dependent on the ability to renew or extend the arrangements beyond the initial contract periods, these expected future cash flows are significantly influenced by the scope and pace of Williams’ producer customers’ drilling programs. Once producer customers’ wells are connected to Williams’ gathering infrastructure, their likelihood of switching to another provider before the wells are abandoned is reduced due to the significant capital investment required.

The amortization expense related to customer relationships was $372 million, $368 million, and $360 million in 2025, 2024, and 2023, respectively. The estimated amortization expense for each of the next five succeeding fiscal years is $364 million, $360 million, $360 million, $360 million, and $359 million.

Transportation and Storage Capacity Contracts

Certain transportation and storage capacity contracts were recognized as intangible assets as part of the acquisition of Sequent in 2021. The amortization expense related to transportation and storage capacity contracts was $10 million, $21 million, and $51 million in 2025, 2024, and 2023, respectively. The estimated amortization expense for each of the next five succeeding fiscal years is $7 million, $4 million, $2 million, $0 million, and $0 million.

Variable Interest Entities (Details) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Dec. 31, 2022

Variable Interest Entity [Line Items]

Equity-method investments

$ 4,518

$ 4,107

$ 4,614

Cash and cash equivalents

2,150

$ 152

Receivables, Net, Current

2,084

1,863

Inventories

314

279

Other current assets and deferred charges

256

191

Property, Plant and Equipment, Net

41,996

38,692

Intangible assets – net

6,763

7,209

Regulatory assets, deferred charges, and other

2,011

1,830

$ 1,573

Accounts payable

(2,224)

(1,613)

Other current liabilities

(1,639)

(1,360)

Regulatory liabilities, deferred income, and other

(4,986)

(5,268)

Changes in ownership of consolidated subsidiaries, net

Total Stockholders' Equity

Variable Interest Entity [Line Items]

Changes in ownership of consolidated subsidiaries, net

(126)

Noncontrolling Interests

Variable Interest Entity [Line Items]

Changes in ownership of consolidated subsidiaries, net

166

Capital in excess of par value [Member]

Variable Interest Entity [Line Items]

Changes in ownership of consolidated subsidiaries, net

(126)

Variable Interest Entity, Primary Beneficiary [Member]

Variable Interest Entity [Line Items]

Cash and cash equivalents

^[1]

Receivables, Net, Current

155

178

^[1]

Inventories

^[1]

Other current assets and deferred charges

^[1]

Property, Plant and Equipment, Net

4,412

4,896

^[1]

Intangible assets – net

1,831

1,940

^[1]

Regulatory assets, deferred charges, and other

^[1]

Accounts payable

(56)

(57)

^[1]

Other current liabilities

(19)

(29)

^[1]

Regulatory liabilities, deferred income, and other

$ (78)

$ (263)

^[1]

Variable Interest Entity, Primary Beneficiary [Member] | Williams Companies Inc [Member] | Driftwood Pipeline LLC

Variable Interest Entity [Line Items]

Variable Interest Entity Ownership Percentage

80.00%

Variable Interest Entity, Not Primary Beneficiary [Member] | Williams Companies Inc [Member]

Variable Interest Entity [Line Items]

Equity-method investments

$ 611

Variable Interest Entity, Not Primary Beneficiary [Member] | Williams Companies Inc [Member] | Louisiana LNG LLC

Variable Interest Entity [Line Items]

Variable Interest Entity Ownership Percentage

10.00%

Equity-method investments

$ 253

Variable Interest Entity, Not Primary Beneficiary [Member] | Williams Companies Inc [Member] | Cogentrix Co-Investment Fund, LP

Variable Interest Entity [Line Items]

Equity-method investments

$ 292

[1]

2024 includes amounts related to Gulfstar One LLC (Gulfstar One), which was a consolidated VIE at December 31, 2024. Williams acquired the remaining interest in Gulfstar One during the fourth quarter of 2025 and it is no longer a VIE. This transaction decreased Noncontrolling interests in consolidated subsidiaries by $166 million, increased Capital in excess of par value by $126 million, and increased Deferred income tax liabilities by $40 million in the Consolidated Balance Sheet.

Regulatory Assets and Liabilities - Williams (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Regulatory Liability [Line Items]
Total regulatory assets	$ 698	$ 666
Total regulatory liabilities	1,319	1,385
Other current assets and deferred charges [Member]
Regulatory Liability [Line Items]
Regulatory Assets, Current	130	84
Regulatory assets, deferred charges, and other [Member]
Regulatory Liability [Line Items]
Regulatory Assets, Noncurrent	568	582
Regulatory liabilities, deferred income, and other [Member]
Regulatory Liability [Line Items]
Regulatory Liabilities, Noncurrent	$ 1,202	$ 1,300

Property, Plant, and Equipment (Details PPE) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Property, Plant, and Equipment

Property, plant, and equipment, at cost

$ 62,010

$ 57,395

Accumulated depreciation and amortization

(20,014)

(18,703)

Property, Plant and Equipment, Net

41,996

38,692

Depreciation and amortization expenses

2,000

1,800

$ 1,700

Interest Costs Capitalized

$ 54

Finite-Lived Intangible Assets, Gross

10,386

10,512

Transcontinental Gas Pipe Line Company, LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

21,012

20,044

Accumulated depreciation and amortization

(6,404)

(5,941)

Property, Plant and Equipment, Net

14,608

14,103

Finite-Lived Intangible Assets, Gross

1,500

Transcontinental Gas Pipe Line Company, LLC [Member] | Onshore Transmission Facilities

Property, Plant, and Equipment

Property, plant, and equipment, at cost

18,093

17,242

Transcontinental Gas Pipe Line Company, LLC [Member] | Offshore Transmission Facilities

Property, Plant, and Equipment

Property, plant, and equipment, at cost

$ 633

659

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.23%

Transcontinental Gas Pipe Line Company, LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, plant, and equipment, at cost

$ 1,010

948

Transcontinental Gas Pipe Line Company, LLC [Member] | Gathering Facilities

Property, Plant, and Equipment

Property, plant, and equipment, at cost

105

136

Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

4,434

4,218

Accumulated depreciation and amortization

(2,164)

(2,089)

Property, Plant and Equipment, Net

2,270

2,129

Northwest Pipeline LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, plant, and equipment, at cost

165

160

Construction in Progress [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

526

420

Construction in Progress [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

111

Other Capitalized Property Plant and Equipment [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

645

639

Other Capitalized Property Plant and Equipment [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

171

Natural gas transmission facilities [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

3,987

3,821

Nonregulated [Member] | Natural gas gathering and processing facilities [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

24,782

23,134

Nonregulated [Member] | Construction in Progress [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

2,947

1,543

Nonregulated [Member] | Oil and Gas Properties

Property, Plant, and Equipment

Property, plant, and equipment, at cost

1,552

1,685

Nonregulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

$ 5,177

4,798

Regulated [Member] | Acquisition Adjustment Of Regulated Facilities [Member]

Property, Plant, and Equipment

Period of straight-line amortization

40 years

Regulated [Member] | Construction in Progress [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

$ 657

542

Regulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

3,009

2,930

Regulated [Member] | Natural gas transmission facilities [Member]

Property, Plant, and Equipment

Property, plant, and equipment, at cost

23,886

22,763

Regulated [Member] | Acquisition Adjustment Of Regulated Facilities [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Plant Acquisition Adjustments for Intangible Utility Plants

$ 319

$ 354

Minimum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Onshore Transmission Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.29%

Minimum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.27%

Minimum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Gathering Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

0.00%

Minimum [Member] | Northwest Pipeline LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

1.60%

Minimum [Member] | Other Capitalized Property Plant and Equipment [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

1.58%

Minimum [Member] | Other Capitalized Property Plant and Equipment [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

0.00%

Minimum [Member] | Natural gas transmission facilities [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.70%

Minimum [Member] | Nonregulated [Member] | Natural gas gathering and processing facilities [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

5 years

Minimum [Member] | Nonregulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

0 years

Minimum [Member] | Regulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

5 years

Property, Plant, and Equipment, Depreciation Rate

^[1]

0.00%

Minimum [Member] | Regulated [Member] | Natural gas transmission facilities [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.23%

Maximum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Onshore Transmission Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

6.67%

Maximum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.31%

Maximum [Member] | Transcontinental Gas Pipe Line Company, LLC [Member] | Gathering Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

0.94%

Maximum [Member] | Northwest Pipeline LLC [Member] | Storage Facilities

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

2.76%

Maximum [Member] | Other Capitalized Property Plant and Equipment [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

20.00%

Maximum [Member] | Other Capitalized Property Plant and Equipment [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

33.33%

Maximum [Member] | Natural gas transmission facilities [Member] | Northwest Pipeline LLC [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

10.20%

Maximum [Member] | Nonregulated [Member] | Natural gas gathering and processing facilities [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

40 years

Maximum [Member] | Nonregulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

45 years

Maximum [Member] | Regulated [Member] | Other Capitalized Property Plant and Equipment [Member]

Property, Plant, and Equipment

Property, Plant and Equipment, Useful Life

^[1]

45 years

Property, Plant, and Equipment, Depreciation Rate

^[1]

33.33%

Maximum [Member] | Regulated [Member] | Natural gas transmission facilities [Member]

Property, Plant, and Equipment

Property, Plant, and Equipment, Depreciation Rate

^[1]

10.20%

[1]	Estimated useful life and depreciation rates are presented as of December 31, 2025. Depreciation rates and estimated useful lives for regulated assets are prescribed by the FERC.

Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions		12 Months Ended
	Nov. 30, 2023	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Feb. 14, 2023
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 466	$ 466	$ 463
Finite-Lived Intangible Assets, Gross		10,386	10,512
Finite-Lived Intangible Assets, Accumulated Amortization		(4,089)	(3,769)
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		10,113	10,239
Finite-Lived Intangible Assets, Accumulated Amortization		(3,832)	(3,523)
Amortization of Intangible Assets		372	368	360
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months		364
Finite-Lived Intangible Assets, Amortization Expense, Year Two		360
Finite-Lived Intangible Assets, Amortization Expense, Year Three		360
Finite-Lived Intangible Assets, Amortization Expense, Year Four		360
Finite-Lived Intangible Assets, Amortization Expense, Year Five		359
Transportation and Storage Capacity [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		267	267
Finite-Lived Intangible Assets, Accumulated Amortization		(254)	(244)
Amortization of Intangible Assets		10	21	51
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months		7
Finite-Lived Intangible Assets, Amortization Expense, Year Two		4
Finite-Lived Intangible Assets, Amortization Expense, Year Three		2
Finite-Lived Intangible Assets, Amortization Expense, Year Four		0
Finite-Lived Intangible Assets, Amortization Expense, Year Five		0
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		6	6
Finite-Lived Intangible Assets, Accumulated Amortization		(3)	(2)
Cureton Acquisition
Finite-Lived Intangible Assets [Line Items]
Goodwill, Period Increase (Decrease)			5
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	20 years
RMM Acquisition
Finite-Lived Intangible Assets [Line Items]
Goodwill, Period Increase (Decrease)			(2)
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	20 years
Transmission, Power & Gulf [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill		400	400	400
Transmission, Power & Gulf [Member] \| MountainWest Acquisition
Finite-Lived Intangible Assets [Line Items]
Goodwill					$ 400
West [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 66	66	$ 63
West [Member] \| Cureton Acquisition
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 11
Goodwill, Period Increase (Decrease)			5
West [Member] \| RMM Acquisition
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 55
Goodwill, Period Increase (Decrease)			$ (2)

Equity-Based Compensation	12 Months Ended
Equity-Based Compensation	Dec. 31, 2025
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Equity-Based Compensation [Text Block]	Note 15 – Equity-Based Compensation Williams’ Plan Information The Williams Companies, Inc. 2007 Incentive Plan (the Plan) provides common-stock-based awards to both employees and nonmanagement directors. To date, 50 million new shares have been authorized for making awards under the Plan. The Plan permits the granting of various types of awards including, but not limited to, restricted stock units and stock options. At December 31, 2025, 13 million shares of common stock were reserved for issuance pursuant to existing and future stock awards, of which 7 million shares were available for future grants. At December 31, 2025, Williams had 0.3 million stock options that were both outstanding and exercisable. Additionally, approximately 0.5 million shares were available for purchase at December 31, 2025 under Williams’ Employee Stock Purchase Plan. Williams recognizes compensation expense on employee stock-based awards on a straight-line basis; forfeitures are recognized when they occur. Operating and maintenance expenses and General and administrative expenses include equity-based compensation expense in 2025, 2024, and 2023 of $93 million, $99 million, and $77 million, respectively. Income tax benefit recognized related to the stock-based compensation expense in 2025, 2024, and 2023 was $22 million, $24 million, and $19 million, respectively. Measured but unrecognized stock-based compensation expense at December 31, 2025, was $78 million, all of which related to restricted stock units. These amounts are expected to be recognized over a weighted-average period of 1.8 years. Nonvested Restricted Stock Units At December 31, 2025 and 2024, Williams had restricted stock units outstanding, including performance-based shares, of 5.1 million shares and 6.4 million shares, respectively. Restricted stock units generally vest after three years. Performance-based grants may vest at a range from zero percent to 200 percent of the original shares granted based on performance against a target. At December 31, 2025, there were 1.6 million performance-based shares outstanding.

Property, Plant, and Equipment

12 Months Ended

Dec. 31, 2025

Property, Plant and Equipment [Abstract]

Property, Plant, and Equipment [Text Block]

Note 9 – Property, Plant, and Equipment

The following tables present Property, plant, and equipment – net for the years ended:

Williams


	Estimated Useful Life (1) (Years)	Depreciation Rates (1) (%)	December 31,
			2025		2024
			(Millions)
Nonregulated:
Natural gas gathering and processing facilities	5 - 40		$	24,782	$	23,134
Construction in progress	Not applicable		2,947		1,543
Oil and gas properties	Units of production		1,552		1,685
Other	0 - 45		5,177		4,798
Regulated:
Natural gas transmission facilities		2.23 - 10.20	23,886		22,763
Construction in progress	Not applicable	Not applicable	657		542
Other	5 - 45	0.00 - 33.33	3,009		2,930
Total property, plant, and equipment, at cost			62,010		57,395
Accumulated depreciation and amortization			(20,014)		(18,703)
Property, plant, and equipment — net			$	41,996	$	38,692

Depreciation expense for Property, plant, and equipment – net was $2.0 billion, $1.8 billion, and $1.7 billion in 2025, 2024, and 2023, respectively.

Interest capitalized was $62 million, $68 million, and $54 million in 2025, 2024, and 2023, respectively.

Regulated Property, plant, and equipment – net includes approximately $319 million and $354 million at December 31, 2025 and 2024, respectively, related to the purchase price allocation of $1.5 billion to property, plant and equipment and adjustments to deferred taxes in excess of original cost from Williams’ purchase of Transco in 1995. This amount is being amortized over 40 years using the straight-line amortization method. Current FERC policy does not permit recovery through rates for amounts in excess of original cost of construction.

Transco


		Depreciation Rates (1) (%)	December 31,
	2025				2024
			(Millions)
Onshore transmission facilities		2.29 - 6.67	$	18,093		$	17,242
Offshore transmission facilities		2.23	633			659
Storage facilities		2.27 - 2.31	1,010			948
Gathering facilities		0.00 - 0.94	105			136
Construction in progress		Not applicable	526			420
Other		1.58 - 20.00	645			639
Total property, plant, and equipment, at cost			21,012			20,044
Accumulated depreciation and amortization			(6,404)			(5,941)
Property, plant, and equipment — net			$	14,608		$	14,103

NWP


	Depreciation Rates (1) (%)	December 31,
		2025		2024
		(Millions)
Transmission facilities	2.70 - 10.20	$	3,987	$	3,821
Storage facilities	1.60 - 2.76	165		160
Construction in progress	Not applicable	111		66
Other	0.00 - 33.33	171		171
Total property, plant, and equipment, at cost		4,434		4,218
Accumulated depreciation and amortization		(2,164)		(2,089)
Property, plant, and equipment — net		$	2,270	$	2,129

__________

(1) Estimated useful life and depreciation rates are presented as of December 31, 2025. Depreciation rates and estimated useful lives for regulated assets are prescribed by the FERC.

Asset Retirement Obligations

Williams’ accrued obligations primarily relate to offshore platforms and pipelines, upstream oil and gas properties, gas transmission pipelines and facilities, underground storage caverns, gas processing, fractionation, and compression facilities, and gas gathering well connections and pipelines. At the end of the useful life of each respective asset, Williams is legally obligated to dismantle offshore platforms and appropriately abandon offshore pipelines, to remove certain components of gas transmission facilities from the ground, to restore land and remove surface equipment at gas processing, fractionation, and compression facilities, to cap certain gathering pipelines at the wellhead connection and remove any related surface equipment, to plug storage caverns and remove any related surface equipment, and to plug producing wells and remove any related surface equipment.

Williams


	Year Ended December 31,
	2025		2024
	(Millions)
Balance at beginning of year	$	2,639	$	2,084
Liabilities incurred, including acquisitions	23		474
Liabilities settled	(110)		(68)
Liabilities reclassified as held for sale	(41)		—
Accretion	133		118
Revisions	(57)		31

Balance at end of year	$	2,587	$	2,639

Transco


	Year Ended December 31,
	2025		2024
	(Millions)
Balance at beginning of year	$	615	$	619
Liabilities incurred	9		—
Liabilities settled	(44)		(32)
Accretion	29		29
Revisions	5		(1)
Balance at end of year	$	614	$	615

The funds Transco collects through a portion of its rates to fund its AROs are deposited into an external trust account dedicated to funding its AROs (ARO Trust). (See Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk.)

NWP


	Year Ended December 31,
	2025		2024
	(Millions)
Balance at beginning of year	$	144	$	136
Accretion	8		8

Balance at end of year	$	152	$	144

NWP’s gross regulatory asset balances associated with ARO as of December 31, 2025 and 2024 were $132 million and $124 million, respectively. NWP’s regulatory asset is expected to be fully recovered through the negative salvage component of depreciation included in NWP’s rates; as such, the negative salvage component of accumulated depreciation collected through rates and reflected as a regulatory liability has been netted with the ARO regulatory asset to result in a regulatory liability of $35 million and $30 million at December 31, 2025 and 2024, respectively (see Note 10 – Regulatory Assets and Liabilities).

Related Party Transactions

12 Months Ended

Dec. 31, 2025

Related Party Transactions [Text Block]

Note 4 – Related Party Transactions

Williams

Transactions with Equity-Method Investees

Williams has Revenues from certain of its equity-method investees of $20 million, $2 million, and $5 million for 2025, 2024, and 2023, respectively. Williams also has costs and expenses associated with its equity-method investees of $180 million, $266 million, and $776 million for 2025, 2024, and 2023, respectively in its Consolidated Statement of Income. Substantially all of these expenses are included in Product costs. In addition, Williams has $4 million and $1 million included in Trade accounts and other receivables and $14 million and $19 million included in Accounts payable in its Consolidated Balance Sheet with its equity-method investees at December 31, 2025 and 2024, respectively.

Williams has operating agreements with certain equity-method investees. These operating agreements typically provide for reimbursement or payment to Williams for certain direct operational payroll and employee benefit costs, materials, supplies, and other charges and also for management services. The total charges to equity-method investees for these fees are $73 million, $52 million, and $64 million for 2025, 2024, and 2023, respectively.

Board of Directors

Two members of Williams’ Board of Directors hold or have held executive officer roles at certain of its counterparties. Williams recorded $97 million, $59 million, and $90 million in Revenues, and $44 million, $40 million, and $25 million in Product costs in its Consolidated Statement of Income from these companies primarily for the sale and purchase of natural gas for 2025, 2024, and 2023, respectively.

Transco and NWP Affiliate Transactions

Benefit Plans

Transco and NWP do not have employees. Certain of the costs charged to them by Williams associated with employees who directly support them are described below. Additionally, allocated corporate expenses from Williams also include amounts related to these same employee benefits, which are not included in the amounts presented immediately below.

Pension and Other Postretirement Benefit Plans

Williams’ pension and other postretirement benefit plans are single-employer plans. However, Transco and NWP follow multiemployer plan accounting whereby the amount charged to them and thus paid by them, is based on their share of net periodic benefit cost (see Note 7 – Employee Benefit Plans).

Pension costs charged to Transco by Williams were $1 million, $1 million, and $2 million for 2025, 2024, and 2023, respectively. NWP received pension credits from Williams of $1 million in 2025, $1 million in 2024, and $0 million in 2023.

Transco recognized other postretirement benefit income of $10 million, $8 million, and $6 million for 2025, 2024, and 2023, respectively, while NWP recognized other postretirement benefit income of $1 million, $1 million, and $0 million, respectively, for the same periods.

Defined Contribution Plan

Williams maintains a defined contribution plan for substantially all of its employees. Williams charged Transco compensation expense of $14 million, $13 million, and $12 million in 2025, 2024, and 2023, respectively, and charged NWP compensation expense of $3 million, $3 million, and $3 million in 2025, 2024, and 2023, respectively, for Williams’ company contributions to this plan.

Employee Stock-Based Compensation Plan Information (see Note 15 – Equity-Based Compensation)

Williams currently bills Transco and NWP directly for compensation expense related to stock-based compensation awards based on the fair value of the awards. Transco and NWP are also billed for their proportionate share of Williams’ and other affiliates’ stock-based compensation expense through various allocation processes.

Total stock-based compensation expense for the years ended December 31, 2025, 2024, and 2023 was $7 million, $6 million, and $6 million, for Transco respectively, and $2 million, $2 million, and $2 million, for NWP, respectively.

Cash Management Program

Transco and NWP are participants in Williams’ cash management program, and thus make advances to and receive advances from Williams. Advances to Williams are represented by demand notes and are classified as Trade accounts and other receivables - Advances to affiliate in the Balance Sheet. Advances from Williams are classified as Payables - Advances from affiliate. Advances are stated at the historical carrying amounts.


	December 31,		December 31,
	2025		2024
	(Millions)
Advances to affiliate
Transco	$	954	$	638
NWP	218		—

Advances from affiliate

NWP	$	—	$	26

Interest expense and income are recognized when earned and the collectability is reasonably assured. The interest rate on intercompany demand notes is based upon the daily overnight investment rate paid on Williams’ excess cash at the end of each month, which was approximately 4 percent at December 31, 2025. Interest income is included in Interest income in the Statement of Net Income for Transco and Other income (expense) – net in the Statement of Net Income for NWP.


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Net interest income from advances
Transco		$	29	$	51	$	81
NWP		3		5		8

Other Affiliate Transactions

Revenues received from affiliates are included in Transco’s Total revenues in the Statement of Net Income. Costs of gas purchased from affiliates are included in Transco’s Natural gas product costs in the Statement of Net Income. All gas purchases are made at market or contracted prices.


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Transco affiliate activity
Total revenues		$	86	$	76	$	56
Natural gas product costs		9		5		7

Services necessary to operate Transco and NWP are provided by Williams and certain affiliates of Williams. Transco and NWP reimburse Williams and its affiliates for all direct and indirect expenses incurred or payments made (including salary, bonus, incentive compensation, and benefits) in connection with these services. Employees of Williams also provide general, administrative, and management services, and Transco and NWP are charged for certain administrative expenses incurred by Williams. These charges are either directly assigned or allocated. Allocated charges are specific or general. Specific allocations are based on metrics that bear a reasonable correlation to the delivery of services. General allocations are based on a three-factor formula, which considers net revenues, gross property, plant, and equipment, and gross payroll. In management’s estimation, the allocation methodologies used are reasonable and result in a reasonable allocation of costs of doing business incurred by Williams. These service expenses are primarily included in Operating and maintenance expenses and General and administrative expenses in the Statement of Net Income.


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Services with affiliates
Transco		$	352	$	344	324
NWP		91		91		86

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-5

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

+ Details

Fair Value Measurements and Guarantees Recurring Measurements and Additional (Details) - USD ($)
$ in Millions

Dec. 31, 2025

Dec. 31, 2024

Energy Related Derivative

Measured on a recurring basis

Derivative Asset

$ 336

$ 344

Derivative Liability

(340)

(400)

Carrying Amount [Member]

Additional disclosures:

Guarantees

(35)

(36)

Long-term debt, including current portion

(28,661)

(26,456)

Carrying Amount [Member] | Gulf Coast Storage Acquisition

Additional disclosures:

Long-term debt, including current portion

(100)

Carrying Amount [Member] | Williams Companies Inc [Member]

Additional disclosures:

Long-term debt, including current portion

(21,649)

(20,167)

Carrying Amount [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(5,888)

(5,235)

Carrying Amount [Member] | Northwest Pipeline LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(748)

(582)

Carrying Amount [Member] | MountainWest [Member]

Additional disclosures:

Long-term debt, including current portion

(376)

(372)

Fair Value [Member]

Additional disclosures:

Guarantees

(28)

Long-term debt, including current portion

(28,629)

(25,830)

Fair Value [Member] | Gulf Coast Storage Acquisition

Additional disclosures:

Long-term debt, including current portion

(100)

Fair Value [Member] | Williams Companies Inc [Member]

Additional disclosures:

Long-term debt, including current portion

(21,556)

(19,517)

Fair Value [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(5,941)

(5,276)

Fair Value [Member] | Northwest Pipeline LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(747)

(573)

Fair Value [Member] | MountainWest [Member]

Additional disclosures:

Long-term debt, including current portion

(385)

(364)

Level 1 [Member]

Additional disclosures:

Guarantees

Long-term debt, including current portion

Level 1 [Member] | Gulf Coast Storage Acquisition

Additional disclosures:

Long-term debt, including current portion

Level 1 [Member] | Williams Companies Inc [Member]

Additional disclosures:

Long-term debt, including current portion

Level 1 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Additional disclosures:

Long-term debt, including current portion

Level 1 [Member] | Northwest Pipeline LLC [Member]

Additional disclosures:

Long-term debt, including current portion

Level 1 [Member] | MountainWest [Member]

Additional disclosures:

Long-term debt, including current portion

Level 2 [Member]

Additional disclosures:

Guarantees

(12)

Long-term debt, including current portion

(28,629)

(25,830)

Level 2 [Member] | Gulf Coast Storage Acquisition

Additional disclosures:

Long-term debt, including current portion

(100)

Level 2 [Member] | Williams Companies Inc [Member]

Additional disclosures:

Long-term debt, including current portion

(21,556)

(19,517)

Level 2 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(5,941)

(5,276)

Level 2 [Member] | Northwest Pipeline LLC [Member]

Additional disclosures:

Long-term debt, including current portion

(747)

(573)

Level 2 [Member] | MountainWest [Member]

Additional disclosures:

Long-term debt, including current portion

(385)

(364)

Level 3 [Member]

Additional disclosures:

Guarantees

(16)

Long-term debt, including current portion

Level 3 [Member] | Gulf Coast Storage Acquisition

Additional disclosures:

Long-term debt, including current portion

Level 3 [Member] | Williams Companies Inc [Member]

Additional disclosures:

Long-term debt, including current portion

Level 3 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Additional disclosures:

Long-term debt, including current portion

Level 3 [Member] | Northwest Pipeline LLC [Member]

Additional disclosures:

Long-term debt, including current portion

Level 3 [Member] | MountainWest [Member]

Additional disclosures:

Long-term debt, including current portion

Fair Value, Recurring [Member] | Carrying Amount [Member] | Energy Related Derivative

Measured on a recurring basis

Derivative Asset

^[1]

336

344

Derivative Liability

^[1]

(340)

(400)

Fair Value, Recurring [Member] | Carrying Amount [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Measured on a recurring basis

ARO Trust investments

356

297

Fair Value, Recurring [Member] | Fair Value [Member]

Measured on a recurring basis

Derivative Asset, Fair Value, Gross Asset

722

726

Derivative Liability, Fair Value, Gross Liability

(915)

(1,070)

Fair Value, Recurring [Member] | Fair Value [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Measured on a recurring basis

ARO Trust investments

356

297

Fair Value, Recurring [Member] | Level 1 [Member]

Measured on a recurring basis

Derivative Asset, Fair Value, Gross Asset

431

427

Derivative Liability, Fair Value, Gross Liability

(497)

(532)

Fair Value, Recurring [Member] | Level 1 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Measured on a recurring basis

ARO Trust investments

356

297

Fair Value, Recurring [Member] | Level 2 [Member]

Measured on a recurring basis

Derivative Asset, Fair Value, Gross Asset

158

188

Derivative Liability, Fair Value, Gross Liability

(270)

(475)

Fair Value, Recurring [Member] | Level 2 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Measured on a recurring basis

ARO Trust investments

Fair Value, Recurring [Member] | Level 3 [Member]

Measured on a recurring basis

Derivative Asset, Fair Value, Gross Asset

133

111

Derivative Liability, Fair Value, Gross Liability

(148)

(63)

Fair Value, Recurring [Member] | Level 3 [Member] | Transcontinental Gas Pipe Line Company, LLC [Member]

Measured on a recurring basis

ARO Trust investments

$ 0

Wiltel Guarantee [Member]

Additional disclosures:

Guarantor Obligations, Maximum Exposure, Undiscounted

Indemnification Agreement [Member] | Carrying Amount [Member]

Additional disclosures:

Guarantees

$ 0

[1]	The carrying amount is presented net of counterparty offsetting arrangements and collateral (see Note 17 – Commodity Derivatives)

EBP Benefit Pymts & Employer Contributions (Details 5) $ in Millions	Dec. 31, 2025 USD ($)
Pension Benefits [Member]
Expected benefit payments
2026	$ 100
2027	95
2028	92
2029	87
2030	83
2031-2035	393
Expected total plans contribution, approximate	1
Other Postretirement Benefits [Member]
Expected benefit payments
2026	11
2027	11
2028	10
2029	10
2030	10
2031-2035	46
Expected total plans contribution, approximate	$ 3

Long-Term Debt Issuances and Retirements (Details) - USD ($)
$ in Millions

Dec. 05, 2025

Dec. 01, 2025

Sep. 15, 2025

Jan. 15, 2025

Jun. 04, 2024

Mar. 04, 2024

Nov. 15, 2023

Jan. 08, 2026

Dec. 31, 2025

Nov. 20, 2025

Jun. 30, 2025

Jan. 09, 2025

Aug. 13, 2024

Jan. 05, 2024

Aug. 10, 2023

Mar. 02, 2023

The Williams Companies, Inc. [Member] | 5.65 Percent Senior Unsecured Notes Due 2033

Debt Instrument [Line Items]

Long-term debt face amount

$ 750

Long-term debt interest rate

5.65%

The Williams Companies, Inc. [Member] | 5.65 Percent Senior Unsecured Notes Due 2033 | Subsequent Event [Member]

Debt Instrument [Line Items]

Long-term debt face amount

^[1]

$ 500

Long-term debt interest rate

^[1]

5.65%

The Williams Companies, Inc. [Member] | 5.15 Percent Senior Unsecured Notes Due 2036 | Subsequent Event [Member]

Debt Instrument [Line Items]

Long-term debt face amount

$ 1,250

Long-term debt interest rate

5.15%

The Williams Companies, Inc. [Member] | 5.95 Percent Senior Unsecured Notes Due 2056 | Subsequent Event [Member]

Debt Instrument [Line Items]

Long-term debt face amount

$ 1,000

Long-term debt interest rate

5.95%

The Williams Companies, Inc. [Member] | 4.625 Percent Senior Unsecured Notes Due 2030 [Member]

Debt Instrument [Line Items]

Long-term debt face amount

$ 750

Long-term debt interest rate

4.625%

The Williams Companies, Inc. [Member] | 5.3 Percent Senior Unsecured Notes Due 2035 [Member]

Debt Instrument [Line Items]

Long-term debt face amount

$ 750

Long-term debt interest rate

5.30%

The Williams Companies, Inc. [Member] | 5.6 Percent Senior Unsecured Notes Due 2035

Debt Instrument [Line Items]

Long-term debt face amount

$ 1,000

Long-term debt interest rate

5.60%

The Williams Companies, Inc. [Member] | 6.0 Percent Senior Unsecured Notes Due 2055

Debt Instrument [Line Items]

Long-term debt face amount

$ 500

Long-term debt interest rate

6.00%

The Williams Companies, Inc. [Member] | 4.8 Percent Senior Unsecured Notes Due 2029

Debt Instrument [Line Items]

Long-term debt face amount

$ 450

Long-term debt interest rate

4.80%

The Williams Companies, Inc. [Member] | 5.15 Percent Senior Unsecured Notes Due 2034

Debt Instrument [Line Items]

Long-term debt face amount

$ 300

^[2]

$ 1,000

Long-term debt interest rate

5.15%

^[2]

5.15%

The Williams Companies, Inc. [Member] | 5.8 Percent Senior Unsecured Notes Due 2054

Debt Instrument [Line Items]

Long-term debt face amount

$ 750

Long-term debt interest rate

5.80%

The Williams Companies, Inc. [Member] | 4.9 Percent Senior Unsecured Notes Due 2029

Debt Instrument [Line Items]

Long-term debt face amount

$ 1,100

Long-term debt interest rate

4.90%

The Williams Companies, Inc. [Member] | 5.40 Percent Senior Unsecured Notes Due 2026

Debt Instrument [Line Items]

Long-term debt face amount

$ 350

^[3]

$ 750

Long-term debt interest rate

5.40%

^[3]

5.40%

The Williams Companies, Inc. [Member] | 5.30 Percent Senior Unsecured Notes Due 2028

Debt Instrument [Line Items]

Long-term debt face amount

$ 900

Long-term debt interest rate

5.30%

The Williams Companies, Inc. [Member] | 4% Senior Unsecured Notes Due 2025 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

4.00%

Extinguishment of Debt, Amount

$ 750

The Williams Companies, Inc. [Member] | 3.9% Senior Unsecured Notes Due 2025 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

3.90%

Extinguishment of Debt, Amount

$ 750

The Williams Companies, Inc. [Member] | 4.55% Senior Unsecured Notes Due 2024 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

4.55%

Extinguishment of Debt, Amount

$ 1,250

The Williams Companies, Inc. [Member] | 4.3% Senior Unsecured Notes Due 2024 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

4.30%

Extinguishment of Debt, Amount

$ 1,000

The Williams Companies, Inc. [Member] | 4.5% Senior Unsecured Notes Due 2023 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

4.50%

Extinguishment of Debt, Amount

$ 600

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.65 Percent Senior Unsecured Notes Due 2033 | Subsequent Event [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

5.65%

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.1 Percent Senior Unsecured Notes Due 2036

Debt Instrument [Line Items]

Long-term debt face amount

^[4]

$ 1,000

Long-term debt interest rate

5.10%

^[4]

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.75 Percent Senior Unsecured Notes Due 2056

Debt Instrument [Line Items]

Long-term debt face amount

^[4]

$ 700

Long-term debt interest rate

5.75%

^[4]

Transcontinental Gas Pipe Line Company, LLC [Member] | 7.85% Senior Unsecured Notes Due 2026 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

7.85%

Extinguishment of Debt, Amount

$ 1,000

Northwest Pipeline LLC [Member] | 7.125% Debentures Due 2025 [Member]

Debt Instrument [Line Items]

Long-term debt interest rate

7.125%

Extinguishment of Debt, Amount

$ 85

[1]	Additional issuance of the 5.65 percent senior notes due 2033 issued on March 2, 2023, and trade interchangeably with such notes.
[2]	Additional issuance of the 5.15 percent senior notes due 2034 issued on January 5, 2024, and trade interchangeably with such notes.
[3]	Additional issuance of the 5.40 percent senior notes due 2026 issued on March 2, 2023, and trade interchangeably with such notes.
[4]	As part of the private debt placement, Transco entered into a registration rights agreement with the initial purchasers of the unsecured notes. Under the terms of the agreement, Transco is obligated to file and consummate a registration statement for an offer to exchange the notes for a new issue of substantially identical notes registered under the Securities Act of 1933, as amended, within 365 days from closing and to use commercially reasonable efforts to complete the exchange offer.

Investing Activities (Details) - USD ($)
$ in Millions

1 Months Ended

3 Months Ended

5 Months Ended

12 Months Ended

Nov. 01, 2024

Aug. 01, 2024

Nov. 30, 2023

Oct. 31, 2025

Mar. 31, 2025

Dec. 31, 2025

Dec. 31, 2023

Dec. 31, 2024

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Schedule of Investments [Line Items]

Equity-method investments

$ 4,518

$ 4,614

$ 4,107

$ 4,518

$ 4,107

$ 4,614

Equity-method investment, difference between carrying amount and underlying equity

509

634

509

634

Equity-method investment, payments to purchase or contributions

511

114

141

Distributions from equity-method investees (Note 8)

800

789

796

Current assets

3,244

$ 4,513

2,661

3,244

2,661

4,513

Current liabilities

(6,106)

(5,312)

(6,106)

(5,312)

Revenues

11,950

10,503

10,907

Net income

2,768

2,346

3,303

Proceeds from dispositions of equity-method investments (Note 8)

161

Equity Method Investment, Realized Gain (Loss) on Disposal

149

Gain on remeasurement of equity-method investment (Note 2)

127

Investment Income, Interest

Investment Income Nonoperating Other

(1)

Other investing income (loss) - net

343

108

Income (Loss) from Equity Method Investments

760

560

589

Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]

Schedule of Investments [Line Items]

Current assets

829

564

829

564

Noncurrent assets

14,525

9,439

14,525

9,439

Current liabilities

(880)

(1,146)

(880)

(1,146)

Noncurrent liabilities

$ (3,147)

(2,383)

(3,147)

(2,383)

Revenues

2,930

^[1]

2,880

3,714

Operating income

1,515

^[1]

1,190

966

Net income

$ 1,296

^[1]

987

748

Appalachia Midstream Investments [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

66.00%

Equity-method investments

^[2]

$ 2,737

2,810

$ 2,737

2,810

Equity-method investment, difference between carrying amount and underlying equity

$ 1,000

1,000

Equity-method investment, payments to purchase or contributions

Distributions from equity-method investees (Note 8)

$ 394

407

405

Overland Pass Pipeline Company LLC [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

50.00%

Equity-method investments

$ 376

385

$ 376

385

Distributions from equity-method investees (Note 8)

$ 101

Blue Racer Midstream LLC [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

50.00%

Equity-method investments

$ 341

366

$ 341

366

Distributions from equity-method investees (Note 8)

$ 118

Blue Racer Midstream LLC [Member] | Northeast G & P [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

50.00%

Louisiana LNG LLC

Schedule of Investments [Line Items]

Equity-method investments

$ 253

Equity-method investment, payments to purchase or contributions

$ 276

$ 313

Louisiana LNG LLC | Transmission, Power & Gulf [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

10.00%

Discovery Producer Services LLC [Member]

Schedule of Investments [Line Items]

Equity-method investment, payments to purchase or contributions

$ 0

Distributions from equity-method investees (Note 8)

$ 0

$ 49

Discovery Producer Services LLC [Member] | Transmission, Power & Gulf [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

60.00%

Gulfstream Natural Gas System, LLC [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

50.00%

Equity-method investments

$ 185

196

$ 185

196

Distributions from equity-method investees (Note 8)

$ 97

103

$ 98

Gulfstream Natural Gas System, LLC [Member] | Transmission, Power & Gulf [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

50.00%

Laurel Mountain Midstream, LLC [Member]

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

69.00%

Equity-method investments

$ 159

171

$ 159

171

Distributions from equity-method investees (Note 8)

Cogentrix Co-Investment Fund, LP

Schedule of Investments [Line Items]

Equity-method investments

^[3]

292

Equity-method investment, payments to purchase or contributions

$ 153

Income (Loss) from Equity Method Investments

$ 153

Cogentrix Co-Investment Fund, LP | Gas & NGL Marketing Services | Indirect Ownership Interest

Schedule of Investments [Line Items]

Equity Method Investment, Ownership Percentage

10.00%

Rocky Mountain Midstream Holdings LLC [Member]

Schedule of Investments [Line Items]

Distributions from equity-method investees (Note 8)

$ 0

Other [Member]

Schedule of Investments [Line Items]

Equity-method investments

$ 175

179

175

179

Equity-method investment, payments to purchase or contributions

Distributions from equity-method investees (Note 8)

Aux Sable Liquid Products LP [Member]

Schedule of Investments [Line Items]

Equity-method investment, payments to purchase or contributions

Aux Sable Liquid Products Inc And Aux Sable Liquid Products LP And Aux Sable Midstream LLC | Northeast G & P [Member]

Schedule of Investments [Line Items]

Proceeds from dispositions of equity-method investments (Note 8)

$ 161

Equity Method Investment, Realized Gain (Loss) on Disposal

149

RMM Acquisition

Schedule of Investments [Line Items]

Gain on remeasurement of equity-method investment (Note 2)

$ 30

Business Combination, Consideration Transferred

$ 704

Discovery Acquisition

Schedule of Investments [Line Items]

Gain on remeasurement of equity-method investment (Note 2)

127

$ 0

$ 127

$ 0

Business Combination, Consideration Transferred

$ 170

Discovery Acquisition | Transmission, Power & Gulf [Member]

Schedule of Investments [Line Items]

Revenues

$ 144

Crowheart Acquisition

Schedule of Investments [Line Items]

Business Combination, Consideration Transferred

$ 307

[1]	Certain equity‑method investments were acquired, sold, or consolidated in the periods presented. The summarized results of operations includes the full‑year results of the investees, while Equity earnings (losses) reflect only the period subsequent to acquisition or prior to the consolidation or disposition.
[2]	Includes equity-method investments in multiple gathering systems in the Marcellus Shale region with an approximate average 66 percent interest.
[3]	See the Cogentrix section below for more details.

Provision (Benefit) for Income Taxes

12 Months Ended

Dec. 31, 2025

Income Tax Disclosure [Abstract]

Provision (Benefit) for Income Taxes [Text Block]

Note 6 – Provision (Benefit) for Income Taxes

Williams has adopted ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures and has applied the disclosure guidance retrospectively for each period presented.

The Provision (benefit) for income taxes includes:


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Current:
Federal		$	99	$	125	$	3
State		14		9		21

		113		134		24
Deferred:
Federal		597		472		872
State		147		34		109

		744		506		981
Provision (benefit) for income taxes		$	857	$	640	$	1,005

Reconciliations from the Provision (benefit) for income taxes at the federal statutory rate to recorded Provision (benefit) for income taxes are as follows:


	Year Ended December 31,
	2025		%		2024		%		2023		%
	(Millions)
Provision (benefit) for income taxes at the federal statutory rate	$	761	21.0	%	$	627	21.0	%	$	925	21.0	%
State and local income tax, net of federal income tax effect	130		3.6	%	35		1.2	%	104		2.4	%



Nontaxable or nondeductible items	(34)		(0.9)	%	(23)		(0.8)	%	(23)		(0.5)	%
Other adjustments	—		0.0	%	1		0.0	%	(1)		0.0	%
Provision (benefit) for income taxes	$	857	23.7	%	$	640	21.4	%	$	1,005	22.9	%

During the course of audits of its business by domestic and foreign tax authorities, Williams frequently faces challenges regarding the amount of taxes due. These challenges include questions regarding the timing and amount of deductions and the allocation of income among various tax jurisdictions. In evaluating the liability associated with its various filing positions, Williams applies the two-step process of recognition and measurement. In association with this liability, Williams records an estimate of related interest and tax exposure as a component of its tax provision. The impact of this accrual is included within Other adjustments in its reconciliation of the Provision (benefit) for income taxes at the federal statutory rate to recorded Provision (benefit) for income taxes.

Significant components of Deferred income tax liabilities are as follows:


	December 31,
	2025		2024
	(Millions)
Gross deferred income tax liabilities:
Property, plant and equipment	$	5,116	$	4,501
Investments	1,718		1,733
Other	237		193
Total gross deferred income tax liabilities	7,071		6,427
Gross deferred income tax assets:
Accrued liabilities	1,142		1,146
Corporate alternative minimum tax credits	203		108

Federal loss carryovers	224		325
Disallowed business interest expense carryforward	117		247
State losses and credits	171		224
Other	127		92
Total gross deferred income tax assets	1,984		2,142
Less valuation allowance	83		91
Net deferred income tax assets	1,901		2,051
Deferred income tax liabilities	$	5,170	$	4,376

The valuation allowance at December 31, 2025 and 2024 serves to reduce the available deferred income tax assets to an amount that will, more likely than not, be realized. Williams considered all available positive and negative evidence, which incorporates available tax planning strategies, and management’s estimate of future reversals of existing taxable temporary differences and has determined that a portion of its deferred income tax assets related to State losses and credits may not be realized. The amounts presented in the table above are, with respect to state items, before any federal benefit. The change from prior year for the State losses and credits reflects increases in losses and credits generated in the current and prior years less losses and/or credits utilized in the current year. Williams has loss and credit carryovers in multiple state taxing jurisdictions. These attributes generally expire between 2026 and 2044 with some carryovers having indefinite carryforward periods.

Corporate alternative minimum tax credits, Federal loss carryovers and Disallowed business interest expense carryforward at December 31, 2025 reflect deferred tax assets on corporate alternative minimum tax credits, net operating loss carryovers and federal interest expense carryforwards. None of these attributes have an expiration date.

Cash payments for income taxes (net of refunds) are as follows:


	Year Ended December 31,
		2025		2024		2023
		(Millions)
U.S. Federal		$	135	$	41	$	11
U.S. State and Local		27		27		20
Total income taxes paid (net of refunds)		$	162	$	68	$	31

On July 4, 2025, the One Big Beautiful Bill Act was enacted. While the new law did not have a significant impact on Williams’ federal income tax provision, Williams did have a temporary deferral of federal income tax payments as a result of permanently restoring full bonus depreciation of certain business property and excluding tax depreciation and amortization in the calculation of the business interest expense limitation.

During the fourth quarter of 2023, Williams closed the audit for 2018 and made a $5 million payment.

Williams recognizes related interest and penalties as a component of Provision (benefit) for income taxes. There were no significant interest and penalties recognized for any period presented. There were no interest or penalties relating to uncertain tax positions accrued as of December 31, 2025 and December 31, 2024.

Consolidated U.S. Federal income tax returns are open to Internal Revenue Service (IRS) examination for tax years after 2021. The statute of limitations for most states expires one year after expiration of the IRS statute.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477617/942-740-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 740
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478822/944-740-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/740/tableOfContent

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-14

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-21

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-17

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-2

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Consolidated Balance Sheet - Williams - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 63	$ 60
Receivables, Net, Current	2,084	1,863
Inventories	314	279
Assets held for sale (Note 3)	318	1
Derivative assets	209	267
Other current assets and deferred charges	256	191
Total current assets	3,244	2,661
Investments	4,559	4,140
Property, Plant and Equipment, Net	41,996	38,692
Intangible assets – net	6,763	7,209
Regulatory assets, deferred charges, and other	2,011	1,830
Total assets	58,573	54,532
Current liabilities:
Accounts payable	2,224	1,613
Liabilities held for sale (Note 3)	63	0
Derivative Liability, Current	135	164
Other current liabilities	1,639	1,360
Commercial paper	700	455
Long-term debt due within one year	1,345	1,720
Total current liabilities	6,106	5,312
Long-term debt	27,316	24,736
Deferred income tax liabilities	5,170	4,376
Regulatory liabilities, deferred income, and other	4,986	5,268
Contingent liabilities and commitments (Note 18)
Stockholders’ equity:
Preferred stock ($1 par value; 30 million shares authorized at December 31, 2025 and December 31, 2024; 35 thousand shares issued at December 31, 2025 and December 31, 2024)	35	35
Common stock ($1 par value; 1,470 million shares authorized at December 31, 2025 and December 31, 2024; 1,261 million shares issued at December 31, 2025 and 1,258 million shares issued at December 31, 2024)	1,261	1,258
Capital in excess of par value	24,801	24,643
Retained deficit	(12,237)	(12,396)
Accumulated other comprehensive income (loss)	127	76
Treasury stock, at cost (39 million shares at December 31, 2025 and December 31, 2024 of common stock)	(1,180)	(1,180)
Total stockholders’ equity	12,807	12,436
Noncontrolling interests in consolidated subsidiaries	2,188	2,404
Total equity	14,995	14,840
Total liabilities and equity	$ 58,573	$ 54,532

Revenue Recognition Contract Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Contract With Customer, Asset [Line Items]
Contract with Customer, Asset, Net - Beginning of Period	$ 98	$ 36
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	86	170
Contract with Customer, Asset, Increase (Decrease) for Contract Acquired in Business Combination	0	36
Contract with Customer, Asset, Reclassified to Receivable	(58)	(144)
Capitalized Contract Cost, Accumulated Amortization	(17)	0
Contract with Customer, Asset, Net - End of Period	109	98
Transcontinental Gas Pipe Line Company, LLC [Member]
Contract With Customer, Asset [Line Items]
Contract with Customer, Asset, Net - Beginning of Period	10	0
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	5	10
Contract with Customer, Asset, Increase (Decrease) for Contract Acquired in Business Combination	0	0
Contract with Customer, Asset, Reclassified to Receivable	0	0
Capitalized Contract Cost, Accumulated Amortization	(2)	0
Contract with Customer, Asset, Net - End of Period	13	10
Northwest Pipeline LLC [Member]
Contract With Customer, Asset [Line Items]
Contract with Customer, Asset, Net - Beginning of Period	21	17
Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	6	6
Contract with Customer, Asset, Increase (Decrease) for Contract Acquired in Business Combination	0	0
Contract with Customer, Asset, Reclassified to Receivable	0	0
Capitalized Contract Cost, Accumulated Amortization	(3)	(2)
Contract with Customer, Asset, Net - End of Period	$ 24	$ 21

Consolidated Statement of Income - Williams - USD ($)
shares in Millions, $ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Revenues:

Revenues

$ 11,950

$ 10,503

$ 10,907

Costs and expenses:

Operating and maintenance expenses

2,282

2,179

1,984

Depreciation, depletion, and amortization expenses

2,347

2,219

2,071

General and administrative expenses

721

708

665

Impairment or write-off of certain assets (Note 16)

212

Gain on sale of business (Note 3)

(129)

Other (income) expense – net

(7)

(60)

(40)

Total costs and expenses

7,754

7,164

6,596

Operating income (loss)

4,196

3,339

4,311

Equity earnings (losses)

760

560

589

Other investing income (loss) – net

343

108

Interest expense

(1,442)

(1,364)

(1,236)

534

^[1]

Other income (expense) – net

108

Income (loss) before income taxes

3,625

2,986

4,405

Less: Provision (benefit) for income taxes

857

640

1,005

Income (loss) from continuing operations

2,768

2,346

3,400

Income (loss) from discontinued operations (Note 1)

(97)

Net income

2,768

2,346

3,303

Less: Net income (loss) attributable to noncontrolling interests

150

121

124

Net income

2,618

2,225

3,179

Less: Preferred stock dividends

Net income (loss) available to common stockholders

2,615

2,222

3,176

Amounts attributable to The Williams Companies, Inc. available to common stockholders:

Income (loss) from continuing operations

2,615

2,222

3,273

Income (loss) from discontinued operations (Note 1)

$ 0

$ (97)

Basic earnings (loss) per common share:

Income (Loss) from Continuing Operations, Per Basic Share

$ 2.14

$ 1.82

$ 2.69

Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share

(0.08)

Net income (loss) available to common stockholders - Basic

$ 2.14

$ 1.82

$ 2.61

Weighted Average Number of Shares Outstanding, Basic

1,221

1,219

1,218

Diluted earnings (loss) per common share:

Income (Loss) from Continuing Operations, Per Diluted Share

$ 2.14

$ 1.82

$ 2.68

Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share

(0.08)

Net income (loss) available to common stockholders - Diluted

$ 2.14

$ 1.82

$ 2.60

Weighted Average Number of Shares Outstanding, Diluted

1,225

1,223

Service [Member]

Revenues:

Revenues

$ 8,348

$ 7,628

$ 7,026

NonRegulated Service Commodity Consideration [Member]

Revenues:

Revenues

192

134

146

Product [Member]

Revenues:

Revenues

3,290

2,991

2,779

Energy Commodities and Service

Revenues:

Revenues

120

(250)

956

Oil and Gas, Purchased [Member]

Costs and expenses:

Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization

2,133

2,075

1,884

Natural Gas Purchased For Shrink [Member]

Costs and expenses:

Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization

$ 66

$ 43

$ 151

[1]	Net gain from Energy Transfer litigation judgment resulted from a favorable ruling in November 2023 (Note 1 – Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies).

Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies [Text Block]

Note 1 – Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies

Description of Business

Williams

Williams is a Delaware corporation whose common stock is listed and traded on the New York Stock Exchange. Its operations are located in the United States and are presented within the following reportable segments: Transmission, Power & Gulf; Northeast G&P; West; and Gas & NGL Marketing Services; consistent with the manner in which Williams’ Chief Executive Officer, the chief operating decision maker (CODM), evaluates performance and allocates resources. All remaining business activities, including upstream operations and corporate activities, are included in Other.

Transmission, Power & Gulf is comprised of interstate natural gas pipelines and their related natural gas storage facilities including Transco, NWP, and MountainWest Pipelines Holding LLC (MountainWest) and a 50 percent equity-method investment in Gulfstream Natural Gas System, L.L.C. (Gulfstream); natural gas gathering and processing (G&P) and crude oil production handling and transportation assets in the Gulf Coast region, including Discovery Producer Services, LLC (Discovery), a former 60 percent equity-method investment in which Williams acquired the remaining ownership interest in August 2024 (see Note 3 – Acquisitions and Divestitures); and natural gas storage facilities and pipelines providing services in north Texas, and also in Louisiana and Mississippi related to the January 2024 Gulf Coast Storage Acquisition (see Note 3 – Acquisitions and Divestitures). Transmission, Power & Gulf also includes power innovation projects under development that will deliver speed-to-market solutions in power grid-constrained markets. This segment was formerly referred to as Transmission & Gulf of America.

Northeast G&P is comprised of Williams’ midstream gathering, processing, and fractionation businesses in the Marcellus Shale region primarily in Pennsylvania and New York, and the Utica Shale region of eastern Ohio, as well as a 65 percent interest in Ohio Valley Midstream LLC (Northeast JV) (a consolidated variable interest entity, or VIE) which operates in West Virginia, Ohio, and Pennsylvania, a 66 percent interest in Cardinal Gas Services, L.L.C. (Cardinal) (a consolidated VIE) which operates in Ohio, a 50 percent equity-method investment in Blue Racer Midstream LLC (Blue Racer), and Appalachia Midstream Services, LLC, a wholly owned subsidiary that owns equity-method investments with an approximate average 66 percent interest in multiple gas gathering systems in the Marcellus Shale region (Appalachia Midstream Investments).

West is comprised of Williams’ gas gathering, processing, and treating operations in the Denver-Julesberg Basin (DJ Basin) and Piceance regions of Colorado, the southwest and Wamsutter regions of Wyoming, the Barnett Shale region of north-central Texas, the Eagle Ford Shale region of south Texas, and the Haynesville Shale region of east Texas and northwest Louisiana. West also included assets in the Anadarko basin in the Mid-Continent region which were classified as held for sale (see Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk). This segment also includes Williams’ natural gas liquid (NGL) storage facilities, an undivided 50 percent interest in a NGL fractionator near Conway, Kansas, and a 50 percent equity-method investment in Overland Pass Pipeline Company LLC (OPPL).

Gas & NGL Marketing Services is comprised of Williams’ NGL and natural gas marketing and trading operations, which include risk management and transactions related to the storage and transportation of natural gas and NGLs on strategically positioned assets, as well as an equity-method investment in Cogentrix Co-Investment Fund, LP (Cogentrix), representing an approximate 10 percent indirect interest in 11 natural gas power plants (see Note 8 – Investing Activities).

Transco

Transco is an interstate natural gas transmission company that owns and operates an interstate natural gas pipeline system extending from Texas, Louisiana, Mississippi and the Gulf of America through Alabama, Georgia, South Carolina, North Carolina, Virginia, Maryland, Delaware, Pennsylvania, and New Jersey to the New York City metropolitan area. The system serves customers in Texas and the 12 southeast and Atlantic seaboard states mentioned above, including major metropolitan areas in Georgia, Washington D.C., Maryland, North Carolina, New York, New Jersey, and Pennsylvania. Transco is a single-member limited liability company, and as such, single-member losses are limited to the amount of its investment.

NWP

NWP owns and operates an interstate pipeline system for the mainline transmission of natural gas. This system extends from the San Juan Basin in northwestern New Mexico and southwestern Colorado through Colorado, Utah, Wyoming, Idaho, Oregon, and Washington to a point on the Canadian border near Sumas, Washington. NWP is a single-member limited liability company, and as such, single-member losses are limited to the amount of its investment.

Basis of Presentation

Discontinued Operations

During 2023, Williams recorded pre-tax charges of $125 million to Income (loss) from discontinued operations in the Consolidated Statement of Income related to litigation associated with its former Alaska refinery. Payments were made in January 2024 and the claims against Williams are now resolved. Except for this item and unless indicated otherwise, the information in the Combined Notes to Financial Statements relates to continuing operations.

Net gain from Energy Transfer Litigation Judgment

In November 2023, Williams received a $627 million payment from Energy Transfer Equity, L.P. (Energy Transfer) for the final order and judgment in connection to a lawsuit for breach of the Agreement and Plan of Merger with Energy Transfer. On the same day, Williams paid attorney fees which had been incurred on a contingent fee basis. This resulted in a net gain of $534 million reported as Net gain from Energy Transfer litigation judgment in the Consolidated Statement of Income for the year ended December 31, 2023.

Summary of Significant Accounting Policies

Principles of Consolidation

•Determining whether an entity is a VIE (see Note 2 – Variable Interest Entities);

•Identifying events that require reconsideration of whether an entity is a VIE and continuously evaluating whether Williams is a VIE’s primary beneficiary;

Use of Estimates

Significant estimates and assumptions may include:

•Impairment assessments of investments, property, plant, and equipment, and intangible assets;

•Litigation-related contingencies;

•Environmental remediation obligations;

•Depreciation and amortization of long-lived assets, which are comprised of property, plant, and equipment, and intangible assets;

•Depreciation and/or amortization of equity-method investment basis differences;

•Asset retirement obligations (AROs);

•Measurement of fair value of commodity derivatives;

•Pension and postretirement valuation variables;

•Measurement of regulatory assets and liabilities;

•Measurement of deferred income tax assets and liabilities, including assumptions related to the realization of deferred income tax assets;

•Revenue recognition, including estimates utilized in recognition of deferred revenue;

•Purchase price accounting.

These estimates are discussed further throughout these combined notes.

Regulatory Accounting

The FERC has prescribed a formula to be used in computing separate allowances for borrowed and equity AFUDC. These allowances are recorded as follows:

Transco


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Allowance for borrowed funds used during construction	$	7	$	17	$	14
Allowance for equity funds used during construction	28		71		63
Allowance for equity and borrowed funds used during construction (AFUDC)	$	35	$	88	$	77

NWP


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Allowance for borrowed funds used during construction	$	2	$	2	$	1
Allowance for equity funds used during construction	7		8		3
Allowance for equity and borrowed funds used during construction (AFUDC)	$	9	$	10	$	4

Revenue Recognition

Service Revenues

Gas pipeline businesses

Midstream businesses

Product Sales

Contract Assets

Williams

Transco and NWP

Contract Liabilities

Williams

Transco

Commodity Derivative Instruments and Hedging Activities

The accounting for the changes in fair value of a commodity derivative can be summarized as follows:


Derivative Treatment						Accounting Method
Normal purchases and normal sales exception						Accrual accounting
All other derivatives						Mark-to-market accounting

Interest Capitalized

Income Taxes

Earnings (Loss) Per Common Share

Cash and Cash Equivalents

Cash and cash equivalents in the Consolidated Balance Sheet consist of highly liquid investments with original maturities of three months or less when acquired.

Accounts Receivable

Gas Imbalances

Transco

NWP

Inventories

Transco and NWP Environmental Matters

Property, Plant, and Equipment

Depreciation for Williams’ nonregulated entities is provided primarily on the straight-line method over estimated useful lives.

Williams follows the successful efforts method of accounting for its upstream properties. Its oil and gas producing property costs are depleted using the units of production method.

Ordinary maintenance and repair costs are generally expensed as incurred. Costs of major renewals and replacements are capitalized as property, plant, and equipment.

Goodwill

Other Identifiable Intangible Assets

Impairment of Property, Plant, and Equipment, Intangible Assets, and Investments

Equity-Method Investment Basis Differences

Leases

When permitted under its lease agreements, Williams may sublease certain unused office space for fixed periods that could extend up to the length of the original lease agreement.

Pension and Other Postretirement Benefits

Contingent Liabilities

Treasury Stock

Cash Flows from Operating Activities

Cash Flows from Revolving Credit Facility and Commercial Paper Program

Accounting Standards Issued But Not Yet Adopted

Share Repurchase Program

In September 2021, Williams’ Board of Directors authorized a share repurchase program with a maximum dollar limit of $1.5 billion. Repurchases may be made from time to time in the open market, by block purchases, in

privately negotiated transactions, or in such other manner as determined by management. Williams will also determine the timing and amount of any repurchases based on market conditions and other factors. The share repurchase program does not obligate Williams to acquire any particular amount of common stock, and it may be suspended or discontinued at any time. This share repurchase program does not have an expiration date. There were no repurchases under the program in 2025 and 2024, and $130 million of repurchases under the program in 2023 which is included in the Consolidated Statement of Changes in Equity. Cumulative repurchases to date under the program total $139 million.

Significant Risks and Uncertainties

Management believes that the carrying value of certain of Williams’ property, plant, and equipment and intangible assets, notably certain assets acquired by Williams accounted for as business combinations between 2012 and 2014, may be in excess of current fair value. However, the carrying value of these assets, in management’s judgment, continues to be recoverable. It is reasonably possible that future strategic decisions, including transactions such as monetizing assets or contributing assets to new ventures with third parties, as well as unfavorable changes in expected producer activities, could impact management’s assumptions and ultimately result in impairments of these assets. Such transactions or developments may also indicate that certain Williams’ equity-method investments have experienced other-than-temporary declines in value, which could result in impairment.

Segment Disclosures Recon from Segment to Consolidated - Revenues, Modified EBITDA, and Significant Expenses (Details)
$ in Millions

12 Months Ended

Dec. 31, 2025

USD ($)

Reportable_segment

Dec. 31, 2024

USD ($)

Dec. 31, 2023

USD ($)

Segment revenues [Line Items]

Revenues

$ 11,950

$ 10,503

$ 10,907

Other financial information:

Other Asset Impairment Charges

(212)

(10)

Gain (Loss) on Disposition of Business

129

Proportional Modified EBITDA Equity Method Investments

(965)

(909)

(939)

534

^[1]

Depreciation, Depletion and Amortization

(2,347)

(2,219)

(2,071)

Income (Loss) from Equity Method Investments

760

560

589

Other investing income (loss) - net

343

108

Interest expense

(1,442)

(1,364)

(1,236)

Asset Retirement Obligation Accretion Expense For Nonregulated Operations

(96)

(81)

(59)

Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest

$ 3,625

2,986

4,405

Number of Reportable Segments | Reportable_segment

Transcontinental Gas Pipe Line Company, LLC [Member]

Segment revenues [Line Items]

Revenues

$ 3,263

2,964

2,866

Other financial information:

Depreciation, Depletion and Amortization

(574)

(545)

(519)

Interest expense

(332)

(324)

Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest

$ 1,426

1,313

1,247

Number of Reportable Segments | Reportable_segment

Northwest Pipeline LLC [Member]

Segment revenues [Line Items]

Revenues

$ 458

444

440

Other financial information:

Depreciation, Depletion and Amortization

(117)

(111)

Interest expense

(28)

Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest

$ 181

180

Number of Reportable Segments | Reportable_segment

Other financial information:

Unrealized Gain (Loss) on Derivatives

$ 2

(6)

(43)

Service [Member]

Segment revenues [Line Items]

Revenues

8,348

7,628

7,026

NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

192

134

146

Product [Member]

Segment revenues [Line Items]

Revenues

3,290

2,991

2,779

Energy Commodities and Service

Segment revenues [Line Items]

Revenues

120

(250)

956

West [Member] | Impairment or write-off of certain assets [Member] | Williams Companies Inc [Member] | Level 3 [Member] | Property, plant, and equipment, net [Member]

Other financial information:

Tangible Asset Impairment Charges

West [Member] | Impairment or write-off of certain assets [Member] | Williams Companies Inc [Member] | Level 2 [Member]

Other financial information:

Impairment of Long-Lived Assets to be Disposed of

176

Operating Segments [Member] | Transmission, Power & Gulf [Member]

Segment revenues [Line Items]

Revenues

5,443

4,628

4,150

Other financial information:

Product Costs And Net Realized Processing Commodity Expenses

(549)

(329)

(259)

Operating And Administrative Expenses

^[2]

(1,142)

(1,104)

(1,034)

Recovery of Direct Costs

^[3]

(247)

(250)

(241)

Other Segment Income (Expenses) - Net

^[4]

155

118

Other Asset Impairment Charges

^[5]

Gain (Loss) on Disposition of Business

^[6]

129

Proportional Modified EBITDA Equity Method Investments

147

173

205

Modified EBITDA

3,720

3,273

3,068

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Energy Related Derivative | Not Designated as Hedging Instrument [Member] | Cost of Sales

Other financial information:

Unrealized Gain (Loss) on Derivatives

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Service [Member]

Segment revenues [Line Items]

Revenues

4,826

4,246

3,858

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Service [Member] | External Customer

Segment revenues [Line Items]

Revenues

4,731

4,157

3,766

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Service [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Transmission, Power & Gulf [Member] | NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

104

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Product [Member]

Segment revenues [Line Items]

Revenues

512

328

252

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Product [Member] | External Customer

Segment revenues [Line Items]

Revenues

156

144

146

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Product [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

356

184

106

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

^[7]

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Energy Commodities and Service | Realized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Transmission, Power & Gulf [Member] | Energy Commodities and Service | Unrealized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Northeast G & P [Member]

Segment revenues [Line Items]

Revenues

2,168

2,025

2,033

Other financial information:

Product Costs And Net Realized Processing Commodity Expenses

(149)

(88)

(125)

Operating And Administrative Expenses

^[2]

(449)

(441)

(424)

Recovery of Direct Costs

^[3]

(172)

(143)

(132)

Other Segment Income (Expenses) - Net

^[4]

(10)

Other Asset Impairment Charges

^[5]

Gain (Loss) on Disposition of Business

^[6]

Proportional Modified EBITDA Equity Method Investments

640

602

574

Modified EBITDA

2,028

1,958

1,916

Operating Segments [Member] | Northeast G & P [Member] | Energy Related Derivative | Not Designated as Hedging Instrument [Member] | Cost of Sales

Other financial information:

Unrealized Gain (Loss) on Derivatives

Operating Segments [Member] | Northeast G & P [Member] | Service [Member]

Segment revenues [Line Items]

Revenues

1,995

1,913

1,896

Operating Segments [Member] | Northeast G & P [Member] | Service [Member] | External Customer

Segment revenues [Line Items]

Revenues

1,980

1,900

1,868

Operating Segments [Member] | Northeast G & P [Member] | Service [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Northeast G & P [Member] | NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Northeast G & P [Member] | Product [Member]

Segment revenues [Line Items]

Revenues

171

110

132

Operating Segments [Member] | Northeast G & P [Member] | Product [Member] | External Customer

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Northeast G & P [Member] | Product [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

122

Operating Segments [Member] | Northeast G & P [Member] | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

^[7]

Operating Segments [Member] | Northeast G & P [Member] | Energy Commodities and Service | Realized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Northeast G & P [Member] | Energy Commodities and Service | Unrealized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | West [Member]

Segment revenues [Line Items]

Revenues

2,847

2,669

2,135

Other financial information:

Product Costs And Net Realized Processing Commodity Expenses

(876)

(844)

(517)

Operating And Administrative Expenses

^[2]

(605)

(591)

(502)

Recovery of Direct Costs

^[3]

(62)

(49)

(37)

Other Segment Income (Expenses) - Net

^[4]

(5)

Other Asset Impairment Charges

(212)

^[5]

(10)

Gain (Loss) on Disposition of Business

^[6]

Proportional Modified EBITDA Equity Method Investments

142

132

162

Modified EBITDA

1,238

1,312

1,238

Operating Segments [Member] | West [Member] | Energy Related Derivative | Not Designated as Hedging Instrument [Member] | Cost of Sales

Other financial information:

Unrealized Gain (Loss) on Derivatives

Operating Segments [Member] | West [Member] | Service [Member]

Segment revenues [Line Items]

Revenues

1,851

1,718

1,502

Operating Segments [Member] | West [Member] | Service [Member] | External Customer

Segment revenues [Line Items]

Revenues

1,621

1,558

1,376

Operating Segments [Member] | West [Member] | Service [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

230

160

126

Operating Segments [Member] | West [Member] | NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

103

Operating Segments [Member] | West [Member] | Product [Member]

Segment revenues [Line Items]

Revenues

906

869

441

Operating Segments [Member] | West [Member] | Product [Member] | External Customer

Segment revenues [Line Items]

Revenues

142

178

Operating Segments [Member] | West [Member] | Product [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

764

691

361

Operating Segments [Member] | West [Member] | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

^[7]

Operating Segments [Member] | West [Member] | Energy Commodities and Service | Realized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | West [Member] | Energy Commodities and Service | Unrealized Gain (Loss)

Segment revenues [Line Items]

Revenues

Operating Segments [Member] | Gas & NGL Marketing Services

Segment revenues [Line Items]

Revenues

^[8]

2,175

1,789

2,878

Other financial information:

Product Costs And Net Realized Processing Commodity Expenses

(1,811)

(1,799)

(1,786)

Operating And Administrative Expenses

^[2]

(93)

(108)

(98)

Recovery of Direct Costs

^[3]

Other Segment Income (Expenses) - Net

^[4]

(1)

Other Asset Impairment Charges

^[5]

Gain (Loss) on Disposition of Business

^[6]

Proportional Modified EBITDA Equity Method Investments

Modified EBITDA

311

(124)

950

Operating Segments [Member] | Gas & NGL Marketing Services | Energy Related Derivative | Not Designated as Hedging Instrument [Member] | Cost of Sales

Other financial information:

Unrealized Gain (Loss) on Derivatives

(6)

(43)

Operating Segments [Member] | Gas & NGL Marketing Services | Service [Member]

Segment revenues [Line Items]

Revenues

^[8]

Operating Segments [Member] | Gas & NGL Marketing Services | Service [Member] | External Customer

Segment revenues [Line Items]

Revenues

^[8]

Operating Segments [Member] | Gas & NGL Marketing Services | Service [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

^[8]

Operating Segments [Member] | Gas & NGL Marketing Services | NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

^[8]

Operating Segments [Member] | Gas & NGL Marketing Services | Product [Member]

Segment revenues [Line Items]

Revenues

^[8]

2,106

2,052

2,060

Operating Segments [Member] | Gas & NGL Marketing Services | Product [Member] | External Customer

Segment revenues [Line Items]

Revenues

^[8]

2,776

2,500

2,382

Operating Segments [Member] | Gas & NGL Marketing Services | Product [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

^[8]

(670)

(448)

(322)

Operating Segments [Member] | Gas & NGL Marketing Services | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

^[7],[8]

(263)

817

Operating Segments [Member] | Gas & NGL Marketing Services | Energy Commodities and Service | Realized Gain (Loss)

Segment revenues [Line Items]

Revenues

^[8]

(69)

115

Operating Segments [Member] | Gas & NGL Marketing Services | Energy Commodities and Service | Unrealized Gain (Loss)

Segment revenues [Line Items]

Revenues

^[8]

138

(335)

702

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment

Segment revenues [Line Items]

Revenues

12,633

11,111

11,196

Other financial information:

Modified EBITDA

7,297

6,419

7,172

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Service [Member]

Segment revenues [Line Items]

Revenues

8,672

7,877

7,257

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Service [Member] | External Customer

Segment revenues [Line Items]

Revenues

8,332

7,615

7,011

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Service [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

340

262

246

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | NonRegulated Service Commodity Consideration [Member]

Segment revenues [Line Items]

Revenues

192

134

146

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Product [Member]

Segment revenues [Line Items]

Revenues

3,695

3,359

2,885

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Product [Member] | External Customer

Segment revenues [Line Items]

Revenues

3,123

2,846

2,642

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Product [Member] | Internal Customer

Segment revenues [Line Items]

Revenues

572

513

243

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

^[7]

(259)

908

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Energy Commodities and Service | Realized Gain (Loss)

Segment revenues [Line Items]

Revenues

(64)

206

Operating Segments [Member] | Reportable Segment, Aggregation before Other Operating Segment | Energy Commodities and Service | Unrealized Gain (Loss)

Segment revenues [Line Items]

Revenues

138

(335)

702

Corporate, Non-Segment | Other Operating Segment

Segment revenues [Line Items]

Revenues

642

444

506

Other financial information:

Modified EBITDA

376

237

307

Corporate, Non-Segment | Other Operating Segment | Energy Commodities and Service

Segment revenues [Line Items]

Revenues

(26)

Corporate, Non-Segment | Other Operating Segment | Other [Member]

Segment revenues [Line Items]

Revenues

632

470

505

Intersegment Eliminations [Member]

Segment revenues [Line Items]

Revenues

$ (1,325)

$ (1,052)

$ (795)

[1]	Net gain from Energy Transfer litigation judgment resulted from a favorable ruling in November 2023 (Note 1 – Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies).
[2]	Segment operating and administrative expenses primarily include payroll, maintenance and operating costs and taxes, and general and administrative expenses, including acquisition and transition-related expenses. It also includes project execution, information technology, finance and accounting, real estate and aviation, central engineering services, safety and operational discipline, supply chain and digital transformation, corporate strategic development, human resources, legal and government affairs, and executive and audit support services costs which are centrally managed and allocated to segments.
[3]	Recoverable power, transportation and storage costs are charges incurred which are reimbursable pursuant to FERC stipulations or customer contracts.
[4]	Other segment income (expenses) primarily includes equity AFUDC and regulatory credits and charges related to Williams’ regulated operations.
[5]	Impairment or write-off of certain assets primarily includes a $25 million write-off of certain compression assets within the West segment in September 2025 and a $176 million impairment of certain gas gathering assets within the West segment in December 2025 (Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk).
[6]	Gain on sale of business reflects a gain recognized on the sale of certain liquids pipelines in the Gulf Coast region in September 2023 (Note 3 – Acquisitions and Divestitures).
[7]	Williams records transactions that qualify as commodity derivatives at fair value with changes in fair value recognized in earnings in the period of change and characterized as unrealized gains or losses. Gains and losses from commodity derivatives held for energy trading purposes are presented on a net basis in revenue.
[8]	As Williams is acting as agent for natural gas marketing customers or engages in energy trading activities, the resulting revenues are presented net of the related costs of those activities.

Long-Term Debt (Details) - USD ($)
$ in Millions

12 Months Ended

Jan. 03, 2024

Dec. 31, 2025

Dec. 31, 2024

Dec. 05, 2025

Dec. 01, 2025

Nov. 20, 2025

^[1]

Sep. 15, 2025

Jun. 30, 2025

Jan. 15, 2025

Jan. 09, 2025

Aug. 13, 2024

Jan. 05, 2024

Aug. 10, 2023

Mar. 02, 2023

Long-term Debt

Debt, Long-Term and Short-Term, Combined Amount

$ 28,661

$ 26,456

Long-term debt due within one year

(1,345)

(1,720)

Long-term debt

27,316

24,736

Gulf Coast Storage Acquisition

Long-term Debt

Business Combination, Consideration Transferred, Liabilities Incurred

$ 100

100

Transcontinental Gas Pipe Line Company, LLC [Member]

Long-term Debt

Unamortized debt issuance costs

(35)

(23)

Debt Instrument, Unamortized Discount (Premium), Net

(15)

(11)

Total long-term debt, including current portion

5,888

5,235

Long-term debt due within one year

(246)

(35)

Transcontinental Gas Pipe Line Company, LLC [Member] | 7.08% Debentures Due 2026 [Member]

Long-term Debt

Long-term debt

$ 8

Long-term debt interest rate

7.08%

Transcontinental Gas Pipe Line Company, LLC [Member] | 7.25% Debentures Due 2026 [Member]

Long-term Debt

Long-term debt

$ 200

200

Long-term debt interest rate

7.25%

Transcontinental Gas Pipe Line Company, LLC [Member] | 7.85% Senior Unsecured Notes Due 2026 [Member]

Long-term Debt

Long-term debt

$ 0

1,000

Long-term debt interest rate

7.85%

Transcontinental Gas Pipe Line Company, LLC [Member] | 4% Senior Unsecured Notes Due 2028 [Member]

Long-term Debt

Long-term debt

$ 400

400

Long-term debt interest rate

4.00%

Transcontinental Gas Pipe Line Company, LLC [Member] | 3.25 Percent Senior Unsecured Notes Due 2030 [Member]

Long-term Debt

Long-term debt

$ 700

700

Long-term debt interest rate

3.25%

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.1 Percent Senior Unsecured Notes Due 2036

Long-term Debt

Long-term debt

$ 1,000

Long-term debt interest rate

5.10%

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.4% Senior Unsecured Notes Due 2041 [Member]

Long-term Debt

Long-term debt

$ 375

375

Long-term debt interest rate

5.40%

Transcontinental Gas Pipe Line Company, LLC [Member] | 4.45% Senior Unsecured Notes Due 2042 [Member]

Long-term Debt

Long-term debt

$ 400

400

Long-term debt interest rate

4.45%

Transcontinental Gas Pipe Line Company, LLC [Member] | 4.6% Senior Unsecured Notes Due 2048 [Member]

Long-term Debt

Long-term debt

$ 600

600

Long-term debt interest rate

4.60%

Transcontinental Gas Pipe Line Company, LLC [Member] | 3.95 Percent Senior Unsecured Notes Due 2050 [Member]

Long-term Debt

Long-term debt

$ 500

500

Long-term debt interest rate

3.95%

Transcontinental Gas Pipe Line Company, LLC [Member] | 5.75 Percent Senior Unsecured Notes Due 2056

Long-term Debt

Long-term debt

$ 700

Long-term debt interest rate

5.75%

Transcontinental Gas Pipe Line Company, LLC [Member] | Atlantic Sunrise [Member]

Long-term Debt

Other financing obligations

$ 734

764

Long-term debt interest rate

9.00%

Transcontinental Gas Pipe Line Company, LLC [Member] | Leidy South

Long-term Debt

Other financing obligations

$ 74

Long-term debt interest rate

13.00%

Transcontinental Gas Pipe Line Company, LLC [Member] | Dalton [Member]

Long-term Debt

Other financing obligations

$ 247

247

Long-term debt interest rate

9.00%

MountainWest [Member]

Long-term Debt

Debt Instrument, Unamortized Discount (Premium), Net

$ (54)

(58)

Total long-term debt, including current portion

376

372

MountainWest [Member] | 3.53 Percent Senior Unsecured Notes due 2028

Long-term Debt

Long-term debt

$ 100

100

Long-term debt interest rate

3.53%

MountainWest [Member] | 3.91 Percent Senior Unsecured Notes due 2038

Long-term Debt

Long-term debt

$ 150

150

Long-term debt interest rate

3.91%

MountainWest [Member] | 4.875 Percent Senior Unsecured Notes due 2041

Long-term Debt

Long-term debt

$ 180

180

Long-term debt interest rate

4.875%

Northwest Pipeline LLC [Member]

Long-term Debt

Unamortized debt issuance costs

$ (1)

(1)

Debt Instrument, Unamortized Discount (Premium), Net

(1)

(2)

Total long-term debt, including current portion

748

582

Long-term debt due within one year

(85)

Northwest Pipeline LLC [Member] | 7.125% Debentures Due 2025 [Member]

Long-term Debt

Long-term debt

$ 0

Long-term debt interest rate

7.125%

Northwest Pipeline LLC [Member] | 4% Senior Unsecured Notes Due 2027 [Member]

Long-term Debt

Long-term debt

$ 500

500

Long-term debt interest rate

4.00%

Northwest Pipeline LLC [Member] | Variable rate Term Loan Due 2028

Long-term Debt

Long-term debt

$ 250

The Williams Companies, Inc. [Member]

Long-term Debt

Credit facility loans

^[2]

Unamortized debt issuance costs

(142)

(130)

Debt Instrument, Unamortized Discount (Premium), Net

(47)

(41)

Total long-term debt, including current portion

21,649

20,167

Long-term debt due within one year

(1,099)

(1,600)

The Williams Companies, Inc. [Member] | 3.9% Senior Unsecured Notes Due 2025 [Member]

Long-term Debt

Long-term debt

$ 0

750

Long-term debt interest rate

3.90%

The Williams Companies, Inc. [Member] | 4% Senior Unsecured Notes Due 2025 [Member]

Long-term Debt

Long-term debt

$ 0

750

Long-term debt interest rate

4.00%

The Williams Companies, Inc. [Member] | 5.40 Percent Senior Unsecured Notes Due 2026

Long-term Debt

Long-term debt

$ 1,100

1,100

Long-term debt interest rate

5.40%

^[3]

5.40%

The Williams Companies, Inc. [Member] | 7.7 Percent Senior Unsecured Notes Due 2027

Long-term Debt

Long-term debt

$ 2

Long-term debt interest rate

7.70%

The Williams Companies, Inc. [Member] | 3.75% Senior Unsecured Notes Due 2027 [Member]

Long-term Debt

Long-term debt

$ 1,450

1,450

Long-term debt interest rate

3.75%

The Williams Companies, Inc. [Member] | 5.30 Percent Senior Unsecured Notes Due 2028

Long-term Debt

Long-term debt

$ 900

900

Long-term debt interest rate

5.30%

The Williams Companies, Inc. [Member] | 4.9 Percent Senior Unsecured Notes Due 2029

Long-term Debt

Long-term debt

$ 1,100

1,100

Long-term debt interest rate

4.90%

The Williams Companies, Inc. [Member] | 4.8 Percent Senior Unsecured Notes Due 2029

Long-term Debt

Long-term debt

$ 450

450

Long-term debt interest rate

4.80%

The Williams Companies, Inc. [Member] | 4.625 Percent Senior Unsecured Notes Due 2030 [Member]

Long-term Debt

Long-term debt

$ 750

Long-term debt interest rate

4.625%

The Williams Companies, Inc. [Member] | 3.5 Percent Senior Unsecured Notes Due 2030 [Member]

Long-term Debt

Long-term debt

$ 1,000

1,000

Long-term debt interest rate

3.50%

The Williams Companies, Inc. [Member] | 2.6 Percent Senior Unsecured Notes Due 2031

Long-term Debt

Long-term debt

$ 1,500

1,500

Long-term debt interest rate

2.60%

The Williams Companies, Inc. [Member] | 7.5% Debentures Due 2031 [Member]

Long-term Debt

Long-term debt

$ 339

339

Long-term debt interest rate

7.50%

The Williams Companies, Inc. [Member] | 7.75% Senior Unsecured Notes Due 2031 [Member]

Long-term Debt

Long-term debt

$ 252

252

Long-term debt interest rate

7.75%

The Williams Companies, Inc. [Member] | 8.75% Senior Unsecured Notes Due 2032 [Member]

Long-term Debt

Long-term debt

$ 445

445

Long-term debt interest rate

8.75%

The Williams Companies, Inc. [Member] | 4.65 Percent Senior Unsecured Notes Due 2032

Long-term Debt

Long-term debt

$ 1,000

1,000

Long-term debt interest rate

4.65%

The Williams Companies, Inc. [Member] | 5.65 Percent Senior Unsecured Notes Due 2033

Long-term Debt

Long-term debt

$ 750

750

Long-term debt interest rate

5.65%

The Williams Companies, Inc. [Member] | 5.15 Percent Senior Unsecured Notes Due 2034

Long-term Debt

Long-term debt

$ 1,300

1,300

Long-term debt interest rate

5.15%

^[4]

5.15%

The Williams Companies, Inc. [Member] | 5.3 Percent Senior Unsecured Notes Due 2035 [Member]

Long-term Debt

Long-term debt

$ 750

Long-term debt interest rate

5.30%

The Williams Companies, Inc. [Member] | 5.6 Percent Senior Unsecured Notes Due 2035

Long-term Debt

Long-term debt

$ 1,000

Long-term debt interest rate

5.60%

The Williams Companies, Inc. [Member] | 6.3% Senior Unsecured Notes Due 2040 [Member]

Long-term Debt

Long-term debt

$ 1,250

1,250

Long-term debt interest rate

6.30%

The Williams Companies, Inc. [Member] | 5.8% Senior Unsecured Notes Due 2043 [Member]

Long-term Debt

Long-term debt

$ 400

400

Long-term debt interest rate

5.80%

The Williams Companies, Inc. [Member] | 5.4% Senior Unsecured Notes Due 2044 [Member]

Long-term Debt

Long-term debt

$ 500

500

Long-term debt interest rate

5.40%

The Williams Companies, Inc. [Member] | 5.75% Senior Unsecured Notes Due 2044 [Member]

Long-term Debt

Long-term debt

$ 650

650

Long-term debt interest rate

5.75%

The Williams Companies, Inc. [Member] | 4.9% Senior Unsecured Notes Due 2045 [Member]

Long-term Debt

Long-term debt

$ 500

500

Long-term debt interest rate

4.90%

The Williams Companies, Inc. [Member] | 5.1% Senior Unsecured Notes Due 2045 [Member]

Long-term Debt

Long-term debt

$ 1,000

1,000

Long-term debt interest rate

5.10%

The Williams Companies, Inc. [Member] | 4.85 Percent Senior Unsecured Notes Due 2048 [Member]

Long-term Debt

Long-term debt

$ 800

800

Long-term debt interest rate

4.85%

The Williams Companies, Inc. [Member] | 3.5 Percent Senior Unsecured Notes Due 2051

Long-term Debt

Long-term debt

$ 650

650

Long-term debt interest rate

3.50%

The Williams Companies, Inc. [Member] | 5.3 Percent Senior Unsecured Notes Due 2052

Long-term Debt

Long-term debt

$ 750

750

Long-term debt interest rate

5.30%

The Williams Companies, Inc. [Member] | 5.8 Percent Senior Unsecured Notes Due 2054

Long-term Debt

Long-term debt

$ 750

750

Long-term debt interest rate

5.80%

The Williams Companies, Inc. [Member] | 6.0 Percent Senior Unsecured Notes Due 2055

Long-term Debt

Long-term debt

$ 500

$ 0

Long-term debt interest rate

6.00%

[1]	As part of the private debt placement, Transco entered into a registration rights agreement with the initial purchasers of the unsecured notes. Under the terms of the agreement, Transco is obligated to file and consummate a registration statement for an offer to exchange the notes for a new issue of substantially identical notes registered under the Securities Act of 1933, as amended, within 365 days from closing and to use commercially reasonable efforts to complete the exchange offer.
[2]	In managing its available liquidity, Williams does not expect a maximum outstanding amount in excess of the capacity of its credit facility inclusive of any outstanding amounts under the commercial paper program.
[3]	Additional issuance of the 5.40 percent senior notes due 2026 issued on March 2, 2023, and trade interchangeably with such notes.
[4]	Additional issuance of the 5.15 percent senior notes due 2034 issued on January 5, 2024, and trade interchangeably with such notes.

Commodity Derivatives - Notional Volumes (Details) - Not Designated as Hedging Instrument [Member]	Dec. 31, 2025 MMBTU Boe
Public Utilities, Inventory, Natural Gas \| IndexRisk
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Nonmonetary Notional Amount Net Long Short Position Volume	1,110,264,783
Public Utilities, Inventory, Natural Gas \| Central Hub Risk
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Nonmonetary Notional Amount Net Long Short Position Volume	(10,941,340)
Public Utilities, Inventory, Natural Gas \| Basis Risk
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Nonmonetary Notional Amount Net Long Short Position Volume	502,600,784
Natural Gas Liquids \| Central Hub Risk
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Nonmonetary Notional Amount Net Long Short Position Volume \| Boe	(456,000)
Natural Gas Liquids \| Basis Risk
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Nonmonetary Notional Amount Net Long Short Position Volume \| Boe	50,000

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Statement of Net Income - NWP - USD ($) $ in Millions	12 Months Ended
Statement of Net Income - NWP - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues [Abstract]
Revenues	$ 11,950	$ 10,503	$ 10,907
Costs and Expenses [Abstract]
Depreciation, depletion, and amortization	2,347	2,219	2,071
General and Administrative Expense	721	708	665
Other Operating Income (Expense), Net	(7)	(60)	(40)
Total costs and expenses	7,754	7,164	6,596
Operating income (loss)	4,196	3,339	4,311
Interest expense	(1,442)	(1,364)	(1,236)
Other Nonoperating Income (Expense)	69	108	99
Net income (loss)	3,625	2,986	4,405
Northwest Pipeline LLC [Member]
Revenues [Abstract]
Revenues	458	444	440
Costs and Expenses [Abstract]
Utilities Operating Expense, Maintenance and Operations	96	95	88
Depreciation, depletion, and amortization	117	111	111
General and Administrative Expense	49	51	51
Taxes, Miscellaneous	15	14	12
Other Operating Income (Expense), Net	(13)	(18)	(16)
Total costs and expenses	264	253	246
Operating income (loss)	194	191	194
Interest expense	(28)	(28)	(28)
Public Utilities, Allowance for Funds Used During Construction, Additions	9	10	4
Other Nonoperating Income (Expense)	6	7	10
Net income (loss)	181	180	180
Natural Gas, US Regulated \| Northwest Pipeline LLC [Member]
Revenues [Abstract]
Revenues	434	416	415
Natural Gas, Storage \| Northwest Pipeline LLC [Member]
Revenues [Abstract]
Revenues	15	15	15
Product and Service, Other \| Northwest Pipeline LLC [Member]
Revenues [Abstract]
Revenues	$ 9	$ 13	$ 10

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2025	Feb. 19, 2026	Jun. 30, 2025
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Document Transition Report	false
Entity Registrant Name	Williams Companies, Inc.
Entity File Number	1-4174
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	73-0569878
Entity Address, Address Line One	One Williams Center
Entity Address, City or Town	Tulsa
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	74172
City Area Code	800
Local Phone Number	945-5426
Title of 12(b) Security	Common Stock, $1.00 par value
Trading Symbol	WMB
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
DocumentFinStmtErrorCorrectionFlag	false
Entity Shell Company	false
Entity Public Float			$ 67,728,227,765
Entity Common Stock, Shares Outstanding		1,221,563,111
Documents Incorporated by Reference [Text Block]	Portions of the Williams’ Definitive Proxy Statement for the Williams’ Annual Meeting of Stockholders to be held on April 28, 2026, are incorporated into Part III, as specifically set forth in Part III.
Entity Central Index Key	0000107263
Amendment Flag	false
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Transcontinental Gas Pipe Line Company, LLC [Member]
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Document Transition Report	false
Entity Registrant Name	Transcontinental Gas Pipe Line Company, LLC
Entity File Number	1-7584
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	74-1079400
Entity Address, Address Line One	2800 Post Oak Boulevard
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77056
City Area Code	713
Local Phone Number	215-2000
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
DocumentFinStmtErrorCorrectionFlag	false
Entity Shell Company	false
Entity Public Float			0
Entity Common Stock, Shares Outstanding		0
Entity Central Index Key	0000099250
Amendment Flag	false
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Northwest Pipeline LLC [Member]
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2025
Document Transition Report	false
Entity Registrant Name	Northwest Pipeline LLC
Entity File Number	1-7414
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-1157701
Entity Address, Address Line One	One Williams Center
Entity Address, City or Town	Tulsa
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	74172
City Area Code	800
Local Phone Number	945-5426
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
DocumentFinStmtErrorCorrectionFlag	false
Entity Shell Company	false
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		0
Entity Central Index Key	0000110019
Amendment Flag	false
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31

Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2025

Retirement Benefits [Abstract]

Changes in Projected Benefit Obligations, Fair Value of Plan Assets, Funded Status, and Schedule of Amounts Recognized in Balance Sheet [Table Text Block]

The following table presents the changes in benefit obligations and plan assets for pension benefits and other postretirement benefits for the years indicated:


	Pension Benefits				Other Postretirement Benefits
	2025		2024		2025		2024
	(Millions)
Change in benefit obligation:
Benefit obligation at beginning of year	$	937	$	1,006	$	132	$	145
Service cost	22		25		1		1
Interest cost	50		47		7		7
Plan participants’ contributions	—		—		1		2
Benefits paid	(89)		(73)		(12)		(11)
Net actuarial loss (gain) (1)	34		(65)		(1)		(12)
Settlements	(5)		(3)		—		—
Net increase (decrease) in benefit obligation	12		(69)		(4)		(13)
Benefit obligation at end of year	949		937		128		132
Change in plan assets:
Fair value of plan assets at beginning of year	1,183		1,167		272		262
Actual return on plan assets	123		88		21		16
Employer contributions	5		4		4		3
Plan participants’ contributions	—		—		1		2
Benefits paid	(89)		(73)		(12)		(11)
Settlements	(5)		(3)		—		—
Net increase (decrease) in fair value of plan assets	34		16		14		10
Fair value of plan assets at end of year	1,217		1,183		286		272
Funded status — overfunded (underfunded)	$	268	$	246	$	158	$	140
Amounts recognized in the Consolidated Balance Sheet:
Noncurrent assets	$	290	$	270	$	161	$	143
Current liabilities	(3)		(4)		(3)		(3)
Noncurrent liabilities	(19)		(20)		—		—
Funded status — overfunded (underfunded)	$	268	$	246	$	158	$	140

Accumulated benefit obligation	$	942	$	929

____________

Defined Benefit Plan, Plan with Projected Benefit Obligation in Excess of Plan Assets [Table Text Block]

The following table summarizes information for pension plans with obligations in excess of plan assets at December 31.


	2025		2024
	(Millions)
Projected benefit obligation	$	22	$	23
Accumulated benefit obligation	20		22
Fair value of plan assets	—		—

Pre-tax amounts recognized in Accumulated other comprehensive income (loss)[Table Text Block]

Pre-tax amounts recognized in Accumulated other comprehensive income (loss) at December 31 are as follows:


	Pension Benefits				Other Postretirement Benefits
	2025		2024		2025		2024
	(Millions)
Net actuarial gain (loss)	$	78	$	49	$	57	$	20

Schedule of Net Benefit Cost (Credit) [Table Text Block]

Net periodic benefit cost (credit) for the years ended December 31 consist of the following:


	Pension Benefits						Other Postretirement Benefits
	2025		2024		2023		2025		2024		2023
	(Millions)
Components of net periodic benefit cost (credit):
Service cost	$	22	$	25	$	23	$	1	$	1	$	1
Interest cost	50		47		46		7		7		7
Expected return on plan assets	(61)		(60)		(57)		(11)		(11)		(10)
Amortization of net actuarial loss (gain)	—		—		5		(9)		(5)		(3)
Net actuarial loss from settlements	1		1		—		—		—		—
Reclassification to regulatory liability	—		—		—		1		—		—
Net periodic benefit cost (credit) (1)	$	12	$	13	$	17	$	(11)	$	(8)	$	(5)

____________

(1) Components other than Service cost are included in Other income (expense) – net below Operating income (loss) in Williams’ Consolidated Statement of Income.

Other changes in plan assets and benefit obligations recognized in other comprehensive income (loss) [Table Text Block]

Other changes in plan assets and benefit obligations recognized in Other comprehensive income (loss) before taxes for the years ended December 31 consist of the following:


	Pension Benefits						Other Postretirement Benefits
	2025		2024		2023		2025		2024		2023
	(Millions)
Net actuarial gain (loss) arising during the year	$	28	$	93	$	(5)	$	8	$	3	$	3
Amortization of net actuarial loss (gain)	—		—		5		(8)		(2)		(2)
Net actuarial loss from settlements	1		1		—		—		—		—
Total recognized in Other comprehensive income (loss)	$	29	$	94	$	—	$	—	$	1	$	1

Defined Benefit Plan, Assumptions [Table Text Block]

The weighted-average assumptions utilized to determine benefit obligations and Net periodic benefit cost (credit) as of December 31 are as follows:


	Pension Benefits						Other Postretirement Benefits
	2025		2024		2023		2025		2024		2023
Benefit obligations:
Discount rate	5.32	%	5.60	%	4.98	%	5.47	%	5.67	%	5.01	%
Rate of compensation increase	3.48		3.48		3.52		N/A		N/A		N/A
Cash balance interest crediting rate	4.25		4.00		4.50		N/A		N/A		N/A
Net periodic benefit cost (credit):
Discount rate	5.60	%	4.98	%	5.16	%	5.67	%	5.01	%	5.20	%
Expected long-term rate of return on plan assets	5.35		5.31		5.17		4.20		4.16		4.04
Rate of compensation increase	3.48		3.52		3.58		N/A		N/A		N/A
Cash balance interest crediting rate	4.00		4.50		3.50		N/A		N/A		N/A

Fair values of plan assets [Table Text Block]

The fair values of Williams’ pension and other postretirement benefits plan assets by asset class at December 31 are as follows:


	2025
	Pension Benefits						Other Postretirement Benefits
	Level 1 (1)		Level 2 (2)		Total		Level 1 (1)		Level 2 (2)		Total
	(Millions)
Cash management funds	$	33	$	—	$	33	$	106	$	—	$	106
Government debt securities	73		18		91		11		3		14
Corporate debt securities	—		297		297		—		45		45
Other	1		11		12		—		1		1
	$	107	$	326	433		$	117	$	49	166
Commingled investment funds (3):
Equities					306						47
Fixed income					478						73
Total assets at fair value					$	1,217					$	286


	2024
	Pension Benefits						Other Postretirement Benefits
	Level 1 (1)		Level 2 (2)		Total		Level 1 (1)		Level 2 (2)		Total
	(Millions)
Cash management funds	$	29	$	—	$	29	$	103	$	—	$	103
Government debt securities	74		19		93		11		3		14
Corporate debt securities	—		295		295		—		43		43
Other	1		4		5		—		—		—
	$	104	$	318	422		$	114	$	46	160
Commingled investment funds (3):
Equities					292						43
Fixed income					469						69
Total assets at fair value					$	1,183					$	272

____________

(1) Level 1 includes assets with fair values based on quoted prices in active markets for identical assets. Cash management funds and U.S. Treasury securities are included in this level.

Expected benefit payments [Table Text Block]

Following are the expected benefit payments, which reflect the same assumptions previously discussed and future service as appropriate.


	Pension Benefits		Other Postretirement Benefits
	(Millions)
2026	$	100	$	11
2027	95		11
2028	92		10
2029	87		10
2030	83		10
2031-2035	393		46

Debt and Banking Arrangements (Tables)

12 Months Ended

Dec. 31, 2025

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

Long-Term Debt by Issuing Entity


	December 31,
	2025		2024
	(Millions)
Transco:
7.080% Debentures due 2026	$	8	$	8
7.250% Debentures due 2026	200		200
7.850% Notes due 2026	—		1,000
4.000% Notes due 2028	400		400
3.250% Notes due 2030	700		700
5.100% Notes due 2036	1,000		—
5.400% Notes due 2041	375		375
4.450% Notes due 2042	400		400
4.600% Notes due 2048	600		600
3.950% Notes due 2050	500		500
5.750% Notes due 2056	700		—
Other financing obligation — Atlantic Sunrise	734		764
Other financing obligation — Leidy South	74		75
Other financing obligation — Dalton	247		247
Unamortized debt issuance costs	(35)		(23)
Net unamortized debt premium (discount)	(15)		(11)
Total debt — Transco	$	5,888	$	5,235
MountainWest:
3.530% Notes due 2028 (Note 3)	$	100	$	100
3.910% Notes due 2038 (Note 3)	150		150
4.875% Notes due 2041 (Note 3)	180		180
Net unamortized debt premium (discount)	(54)		(58)
Total debt — MountainWest	$	376	$	372
NWP:
7.125% Debentures due 2025	$	—	$	85
4.000% Notes due 2027	500		500
Term loan due 2028 (see NWP Credit Agreement)	250		—
Unamortized debt issuance costs	(1)		(1)
Net unamortized debt premium (discount)	(1)		(2)
Total debt — NWP	$	748	$	582
Williams:
3.900% Notes due 2025	$	—	$	750
4.000% Notes due 2025	—		750
5.400% Notes due 2026	1,100		1,100
7.700% Notes due 2027	2		2
3.750% Notes due 2027	1,450		1,450
5.300% Notes due 2028	900		900
4.900% Notes due 2029	1,100		1,100
4.800% Notes due 2029	450		450
4.625% Notes due 2030	750		—
3.500% Notes due 2030	1,000		1,000


	December 31,
	2025		2024
	(Millions)
2.600% Notes due 2031	$	1,500	$	1,500
7.500% Debentures due 2031	339		339
7.750% Notes due 2031	252		252
8.750% Notes due 2032	445		445
4.650% Notes due 2032	1,000		1,000
5.650% Notes due 2033	750		750
5.150% Notes due 2034	1,300		1,300
5.300% Notes due 2035	750		—
5.600% Notes due 2035	1,000		—
6.300% Notes due 2040	1,250		1,250
5.800% Notes due 2043	400		400
5.400% Notes due 2044	500		500
5.750% Notes due 2044	650		650
4.900% Notes due 2045	500		500
5.100% Notes due 2045	1,000		1,000
4.850% Notes due 2048	800		800
3.500% Notes due 2051	650		650
5.300% Notes due 2052	750		750
5.800% Notes due 2054	750		750
6.000% Notes due 2055	500		—

Unamortized debt issuance costs	(142)		(130)
Net unamortized debt premium (discount)	(47)		(41)
Total debt — Williams	$	21,649	$	20,167
Gulf Coast Storage deferred consideration obligation (Note 3)	—		100
Total debt	$	28,661	$	26,456
Long-term debt due within one year — Williams	(1,099)		(1,600)
Long-term debt due within one year — Transco	(246)		(35)
Long-term debt due within one year — NWP	—		(85)
Long-term debt	$	27,316	$	24,736

Schedule of Maturities of Long-term Debt [Table Text Block]

The following table presents aggregate minimum maturities of long-term debt and other financing obligations, excluding net unamortized debt premium (discount) and debt issuance costs, for each of the next five years:


	December 31, 2025
	(Millions)
Williams:
2026	$	1,345
2027	1,994
2028	1,696
2029	1,600
2030	2,504

Transco:
2026	$	246
2027	42
2028	446
2029	50
2030	754

NWP:
2027	$	500
2028	250

Schedule of Debt Issuances

Senior unsecured debt issuances for the past three years and subsequent to the balance sheet date are as follows:


Issue Date	Maturity Date	Amount		Rate
		(Millions)
Williams Public Issuances:
January 8, 2026 (1)	March 15, 2033	$	500	5.650%
January 8, 2026	March 15, 2036	1,250		5.150%
January 8, 2026	March 15, 2056	1,000		5.950%
June 30, 2025	June 30, 2030	750		4.625%
June 30, 2025	September 30, 2035	750		5.300%
January 9, 2025	March 15, 2035	1,000		5.600%
January 9, 2025	March 15, 2055	500		6.000%
August 13, 2024	November 15, 2029	450		4.800%
August 13, 2024 (2)	March 15, 2034	300		5.150%
August 13, 2024	November 15, 2054	750		5.800%
January 5, 2024	March 15, 2029	1,100		4.900%
January 5, 2024	March 15, 2034	1,000		5.150%
August 10, 2023 (3)	March 2, 2026	350		5.400%
August 10, 2023	August 15, 2028	900		5.300%
March 2, 2023	March 2, 2026	750		5.400%
March 2, 2023	March 15, 2033	750		5.650%
Transco Private Placements:
November 20, 2025 (4)	March 15, 2036	$	1,000	5.100%
November 20, 2025 (4)	March 15, 2056	700		5.750%

________________

(1) Additional issuance of the 5.65 percent senior notes due 2033 issued on March 2, 2023, and trade interchangeably with such notes.

(2) Additional issuance of the 5.15 percent senior notes due 2034 issued on January 5, 2024, and trade interchangeably with such notes.

(3) Additional issuance of the 5.40 percent senior notes due 2026 issued on March 2, 2023, and trade interchangeably with such notes.

(4) As part of the private debt placement, Transco entered into a registration rights agreement with the initial purchasers of the unsecured notes. Under the terms of the agreement, Transco is obligated to file and consummate a registration statement for an offer to exchange the notes for a new issue of substantially identical notes registered under the Securities Act of 1933, as amended, within 365 days from closing and to use commercially reasonable efforts to complete the exchange offer.

Schedule of Extinguishment of Debt

Senior unsecured public debt retirements for the past three years are as follows:


Date of Retirement	Maturity Date	Amount		Rate
		(Millions)
Williams:
September 15, 2025	September 15, 2025	$	750	4.000%
January 15, 2025	January 15, 2025	750		3.900%
June 4, 2024	June 4, 2024	1,250		4.550%
March 4, 2024	March 4, 2024	1,000		4.300%
November 15, 2023	November 15, 2023	600		4.500%
Transco:
December 5, 2025	February 1, 2026	$	1,000	7.850%
NWP:
December 1, 2025	December 1, 2025	$	85	7.125%

Schedule of Line of Credit Facilities [Table Text Block]

Credit Facility


	December 31, 2025
	Stated Capacity		Outstanding
	(Millions)
Long-term credit facility (1)	$	3,750	$	—
Letters of credit under certain bilateral bank agreements			15

________________

(1) In managing its available liquidity, Williams does not expect a maximum outstanding amount in excess of the capacity of its credit facility inclusive of any outstanding amounts under the commercial paper program.

Interest Income and Interest Expense Disclosure

Cash Payments for Interest by Registrant (Net of Amounts Capitalized)


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Williams	$	1,404	$	1,293	$	1,152
Transco	336		302		307
NWP	24		24		26

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 6: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69E

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-8

Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-6

Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-7

+ Details

Schedule II Valuation and Qualifying Accounts (Details) - Deferred Tax Asset Valuation Allowance [Member] - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Valuation And Qualifying Accounts

Beginning Balance

^[1]

$ 91

$ 183

$ 200

Additions Charged (Credited) To Cost and Expenses

(8)

(92)

(17)

Additions Other

Deductions

Ending Balance

^[1]

$ 83

$ 91

$ 183

[1]	Deducted from related assets.

EBPs Funded Status (Details) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Defined Contribution Plan

Percentage of eligible compensation the employer will match of employee contributions

6.00%

Employer's contributions charged to expense under defined contribution plan

$ 74

$ 69

$ 60

Pension Benefits [Member]

Change in benefit obligation:

Benefit obligation at beginning of year

937

1,006

Service cost

Interest cost

Plan participants’ contributions

Benefits paid

(89)

(73)

Net actuarial loss (gain) (1)

^[1]

(65)

Settlements

(5)

(3)

Net increase (decrease) in benefit obligation

(69)

Benefit obligation at end of year

949

937

1,006

Other Postretirement Benefits [Member]

Change in benefit obligation:

Benefit obligation at beginning of year

132

145

Service cost

Interest cost

Plan participants’ contributions

Benefits paid

(12)

(11)

Net actuarial loss (gain) (1)

^[1]

(1)

(12)

Settlements

Net increase (decrease) in benefit obligation

(4)

(13)

Benefit obligation at end of year

$ 128

$ 132

$ 145

[1]

2025 amounts are due primarily to changes in the following factors: Pension Benefits - discount rate assumptions and interest crediting rate assumption. 2024 amounts are due primarily to changes in the following factors: Pension Benefits - discount rate assumptions and interest crediting rate assumption; Other Postretirement Benefits - discount rate assumption.

Acquisitions and Divestitures (Tables)

12 Months Ended

Dec. 31, 2025

Business Combination [Line Items]

Business Combination, Pro Forma Information [Table Text Block]

The following pro forma Revenues and Net income (loss) attributable to The Williams Companies, Inc. for 2024 and 2023, respectively, are presented as if the Crowheart Acquisition, Discovery Acquisition, and Gulf Coast Storage Acquisition had been completed on January 1, 2023, and the DJ Basin Acquisitions and MountainWest Acquisition had been completed on January 1, 2022. These pro forma amounts are not necessarily indicative of what the actual results would have been if the acquisitions had in fact occurred on the dates or for the periods indicated, nor do they purport to project Revenues or Net income (loss) attributable to The Williams Companies, Inc. for any future periods or as of any date. These amounts do not give effect to any potential cost savings, operating synergies, or revenue enhancements to result from the transactions or the potential costs to achieve these cost savings, operating synergies, and revenue enhancements.




















	Year Ended December 31, 2024
	As Reported		Pro Forma Crowheart (1)		Pro Forma Discovery (1)								Pro Forma Combined
	(Millions)
Revenues	$	10,503	$	60	$	58							$	10,621
Net income (loss) attributable to The Williams Companies, Inc.	2,225		8		(5)								2,228

	Year Ended December 31, 2023
	As Reported		Pro Forma Crowheart		Pro Forma Discovery		Pro Forma Gulf Coast Storage		Pro Forma DJ Basin (1)		Pro Forma MountainWest (1)		Pro Forma Combined
	(Millions)
Revenues	$	10,907	$	74	$	129	$	202	$	270	$	35	$	11,617
Net income (loss) attributable to The Williams Companies, Inc.	3,179		19		(1)		53		17		6		3,273

(1)Excludes results from operations acquired in the acquisition for the period beginning on the acquisition date, as these results are included in the amounts as reported.

Crowheart Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at November 1, 2024. After the December 31, 2024, financial statements were issued, Williams identified adjustments to the preliminary purchase price allocation, resulting in decreases of $56 million in property, plant, and equipment and $56 million in noncurrent liabilities.


	(Millions)
Cash and cash equivalents	$	94
Other current assets	15
Property, plant, and equipment – net	345
Other noncurrent assets	2
Total assets acquired	456

Current liabilities	(45)
Noncurrent liabilities	(59)
Total liabilities assumed	(104)

Net assets acquired	$	352

Discovery Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at August 1, 2024. The valuation technique used consisted of the cost approach for property, plant, and equipment.


	(Millions)
Cash and cash equivalents	$	22
Other current assets	19
Property, plant, and equipment – net	941
Other noncurrent assets	39
Total assets acquired	1,021

Current liabilities	(40)
Noncurrent liabilities	(296)
Total liabilities assumed	(336)

Net assets acquired	$	685

Gulf Coast Storage Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at January 3, 2024.


	(Millions)
Cash and cash equivalents	$	46
Other current assets	18
Property, plant, and equipment – net	2,035
Other noncurrent assets	2
Total assets acquired	2,101

Current liabilities	(11)
Noncurrent liabilities	(107)
Total liabilities assumed	(118)

Net assets acquired	$	1,983

Cureton Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at November 30, 2023.


	(Millions)
Cash and cash equivalents	$	6
Other current assets	21
Property, plant, and equipment – net	433
Intangible assets – net	117
Other noncurrent assets	1
Total identifiable assets acquired	578

Current liabilities	(29)
Noncurrent liabilities	(14)
Total liabilities assumed	(43)

Net identifiable assets acquired	535

Goodwill included in Intangible assets – net	11
Net assets acquired	$	546

RMM Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at November 30, 2023. The net assets acquired primarily reflect the noncash consideration transferred, which includes the fair value of both Williams’ previous equity-method investment and the deferred consideration obligation.


	(Millions)
Cash and cash equivalents	$	28
Other current assets	4
Investments	20
Property, plant, and equipment – net	1,041
Intangible assets – net	63
Other noncurrent assets	12
Total identifiable assets acquired	1,168

Current liabilities	(44)
Noncurrent liabilities	(103)
Total liabilities assumed	(147)

Net identifiable assets acquired	1,021

Goodwill included in Intangible assets – net	55
Net assets acquired	$	1,076

MountainWest Acquisition

Business Combination [Line Items]

Business Combination, Recognized Asset Acquired and Liability Assumed

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at February 14, 2023. The fair value of accounts receivable acquired equals contractual amounts receivable.


	(Millions)
Cash and cash equivalents	$	23
Trade accounts and other receivables	33
Other current assets	26
Investments	20
Property, plant, and equipment – net	1,019
Other noncurrent assets	33
Total identifiable assets acquired	1,154

Current liabilities	(47)
Long-term debt	(365)
Other noncurrent liabilities	(95)
Total liabilities assumed	(507)

Net identifiable assets acquired	647

Goodwill included in Intangible assets – net	400
Net assets acquired	$	1,047

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Balance Sheet - Transco - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Assets, Current [Abstract]
Cash and cash equivalents	$ 63	$ 60
Inventory, Net	314	279
Other current assets and deferred charges	256	191
Current assets	3,244	2,661
Property, Plant and Equipment, Net	41,996	38,692
Other Assets, Noncurrent	2,011	1,830
Total assets	58,573	54,532
Liabilities, Current [Abstract]
Accounts payable	2,224	1,613
Other current liabilities	1,639	1,360
Total current liabilities	6,106	5,312
Contingent liabilities and commitments
Members' Equity [Abstract]
Retained Earnings (Accumulated Deficit)	(12,237)	(12,396)
Total liabilities and equity	58,573	54,532
Transcontinental Gas Pipe Line Company, LLC [Member]
Assets, Current [Abstract]
Cash and cash equivalents	0	0
Accounts and Other Receivables, Net, Current	23	12
Inventory, Net	82	81
Regulatory Assets, Current	126	74
Other current assets and deferred charges	24	24
Current assets	1,522	1,103
Property, Plant and Equipment, Net	14,608	14,103
Regulatory Assets, Noncurrent	268	320
Other Assets, Noncurrent	466	405
Total assets	16,864	15,931
Liabilities, Current [Abstract]
Accounts Payable, Trade, Current	225	258
Regulatory Liability, Current	93	58
Interest Payable, Current	53	76
Customer Refund Liability, Current	179	0
Accrued Liabilities and Other Liabilities	75	0
Other current liabilities	143	105
Asset Retirement Obligation, Current	41	22
Long-Term Debt, Current Maturities	246	35
Total current liabilities	1,117	609
Long-Term Debt, Excluding Current Maturities	5,642	5,200
Regulatory Liabilities, Noncurrent	914	976
Asset Retirement Obligations, Noncurrent	573	593
Other Liabilities, Noncurrent	227	248
Contingent liabilities and commitments
Members' Equity [Abstract]
Members' Capital	5,088	5,088
Retained Earnings (Accumulated Deficit)	3,303	3,217
Total Members' Equity	8,391	8,305
Total liabilities and equity	16,864	15,931
Transcontinental Gas Pipe Line Company, LLC [Member] \| Related Party
Assets, Current [Abstract]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current	954	638
Accounts Receivable, after Allowance for Credit Loss, Current	7	24
Liabilities, Current [Abstract]
Accounts payable	62	55
Transcontinental Gas Pipe Line Company, LLC [Member] \| Nonrelated Party
Assets, Current [Abstract]
Accounts Receivable, after Allowance for Credit Loss, Current	$ 306	$ 250

Consolidated Statement of Changes in Equity (Parenthetical) - Williams - $ / shares	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Stockholders' Equity [Abstract]
Common Stock, Dividends, Per Share, Declared	$ 2.00	$ 1.90	$ 1.79

Provision (Benefit) for Income Taxes Cash Payments and Textuals (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Contingency [Line Items]
Income Tax Paid, Federal, after Refund Received	$ 135	$ 41	$ 11
Income Tax Paid, State and Local, after Refund Received	27	27	20
Income Taxes Paid	162	68	31
Total interest and penalties accrued as uncertain tax positions	$ 0	$ 0
Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Income Taxes Paid			$ 5

Acquisitions and Divestitures

12 Months Ended

Dec. 31, 2025

Business Combination [Abstract]

Acquisitions and Divestitures [Text Block]

Note 3 – Acquisitions and Divestitures

Crowheart Acquisition

As of December 31, 2023, Williams had an agreement regarding certain crude oil and natural gas properties in the Wamsutter basin in Wyoming under which it owned a 75 percent undivided interest in each well’s working interest and proportionally consolidated its undivided interest. On November 1, 2024, Williams closed on the acquisition of a third-party operator, Crowheart Energy, LLC, for $307 million cash, subject to working capital and post-closing adjustments (Crowheart Acquisition). After closing on the acquisition, Williams owns more than a 90 percent working interest in each well. The purpose of this acquisition was to consolidate Williams’ interests in the Wamsutter basin and further optimize development in the area to continue to supply its gathering and processing assets. Assets acquired, acquisition-related costs incurred, and results of operations realized are included at Other.

During the period from the acquisition date of November 1, 2024 to December 31, 2024, the additional interest acquired in the Crowheart Acquisition contributed Revenues of $20 million and Modified EBITDA (as defined in Note 19 – Segment Disclosures) of $7 million.

Acquisition-related costs for the Crowheart Acquisition total $2 million and are included in General and administrative expenses.

Williams accounted for the Crowheart Acquisition as a business combination, which requires, among other things, that identifiable assets acquired and liabilities assumed be recognized at their acquisition date fair values. The valuation techniques used for property, plant, and equipment consisted of the income approach for proved developed producing reserves and the market approach for undeveloped reserves.


	(Millions)
Cash and cash equivalents	$	94
Other current assets	15
Property, plant, and equipment – net	345
Other noncurrent assets	2
Total assets acquired	456

Current liabilities	(45)
Noncurrent liabilities	(59)
Total liabilities assumed	(104)

Net assets acquired	$	352

Discovery Acquisition

As of December 31, 2023, Williams owned a 60 percent interest in Discovery, which it accounted for as an equity-method investment. On August 1, 2024, Williams closed on the acquisition of the remaining 40 percent interest in Discovery, along with certain other assets, for $170 million cash, subject to working capital and post-closing adjustments (Discovery Acquisition). As a result of acquiring this additional interest, Williams obtained control and subsequently consolidates Discovery. The purpose of this acquisition was to expand Williams’ gathering, processing, and transportation presence in the Gulf of America region. Assets acquired, acquisition-related costs incurred, and results of operations realized are included within Williams’ Transmission, Power & Gulf segment.

During the period from the acquisition date of August 1, 2024 to December 31, 2024, the operations acquired in the Discovery Acquisition contributed Revenues of $144 million and Modified EBITDA of $42 million.

Acquisition-related costs for the Discovery Acquisition total $1 million, incurred in 2024, and are included in General and administrative expenses.

Williams accounted for the Discovery Acquisition as a business combination. The book value of its existing equity-method investment prior to the acquisition date of August 1, 2024, was $381 million. Williams recognized a $127 million gain on remeasuring its existing equity-method investment to fair value included in Other investing income (loss) – net in the third quarter of 2024, which is not included in the pro forma Discovery adjustments below. Williams utilized the income approach to fair value its previous equity-method investment in Discovery.


	(Millions)
Cash and cash equivalents	$	22
Other current assets	19
Property, plant, and equipment – net	941
Other noncurrent assets	39
Total assets acquired	1,021

Current liabilities	(40)
Noncurrent liabilities	(296)
Total liabilities assumed	(336)

Net assets acquired	$	685

Gulf Coast Storage Acquisition

On January 3, 2024, Williams closed on the acquisition from Hartree Partners LP for $1.95 billion of 100 percent of a strategic portfolio of natural gas storage facilities and pipelines, located in Louisiana and Mississippi (Gulf Coast Storage Acquisition). The purpose of this acquisition was to expand Williams’ natural gas storage footprint in the Gulf Coast region. Assets acquired, acquisition-related costs incurred, and results of operations realized are included within Williams’ Transmission, Power & Gulf segment. The Gulf Coast Storage Acquisition was funded with cash on hand and $100 million of deferred consideration that did not accrue interest and was paid on January 3, 2025.

During the period from the acquisition date of January 3, 2024 to December 31, 2024, the operations acquired in the Gulf Coast Storage Acquisition contributed Revenues of $228 million and Modified EBITDA of $160 million, which is impacted by acquisition-related costs. Acquisition-related costs for the Gulf Coast Storage Acquisition total $15 million, including $14 million incurred in 2024, and are included in General and administrative expenses.

Williams accounted for the Gulf Coast Storage Acquisition as a business combination. The valuation technique used consisted of the cost approach for property, plant, and equipment.

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at January 3, 2024.


	(Millions)
Cash and cash equivalents	$	46
Other current assets	18
Property, plant, and equipment – net	2,035
Other noncurrent assets	2
Total assets acquired	2,101

Current liabilities	(11)
Noncurrent liabilities	(107)
Total liabilities assumed	(118)

Net assets acquired	$	1,983

DJ Basin Acquisitions

Cureton Acquisition

On November 30, 2023, Williams closed on the acquisition of 100 percent of Cureton Front Range, LLC (Cureton Acquisition), whose operations are located in the DJ Basin, for $546 million. The purpose of this acquisition was to expand Williams’ gathering and processing footprint and create operational synergies for its operations in the DJ Basin. Assets acquired, acquisition-related costs incurred, and results of operations realized are included within Williams’ West segment. The Cureton Acquisition was funded with cash on hand.

During the period from the acquisition date of November 30, 2023 to December 31, 2023, the operations acquired in the Cureton Acquisition contributed Revenues of $35 million and Modified EBITDA of $7 million.

Acquisition-related costs for the Cureton Acquisition total $8 million, including $6 million incurred in 2023, and are included in General and administrative expenses.

Williams accounted for the Cureton Acquisition as a business combination. The valuation techniques used consisted of the cost approach for property, plant, and equipment and the income approach for valuation of other intangible assets.

The following table presents the allocation of the acquisition date fair value of the major classes of the assets acquired and liabilities assumed at November 30, 2023.


	(Millions)
Cash and cash equivalents	$	6
Other current assets	21
Property, plant, and equipment – net	433
Intangible assets – net	117
Other noncurrent assets	1
Total identifiable assets acquired	578

Current liabilities	(29)
Noncurrent liabilities	(14)
Total liabilities assumed	(43)

Net identifiable assets acquired	535

Goodwill included in Intangible assets – net	11
Net assets acquired	$	546

Other intangible assets recognized in the Cureton Acquisition are related to contractual customer relationships from gas gathering and processing agreements with customers. The basis for determining the value of these intangible assets is estimated future net cash flows to be derived from acquired contractual customer relationships discounted using a risk-adjusted discount rate. These intangible assets are being amortized on a straight-line basis over an initial period of 20 years which represents the term over which the contractual customer relationships are expected to contribute to Williams’ cash flows. Approximately 24 percent of the expected future revenues from these contractual customer relationships are impacted by Williams’ ability and intent to renew or renegotiate existing customer contracts. Williams expenses costs incurred to renew or extend the terms of its gas gathering contracts with customers. Based on the estimated future revenues during the current contract periods (as estimated at the time of the acquisition), the weighted-average period prior to the next renewal or extension of the existing contractual customer relationships is approximately 10 years. See Note 11 – Goodwill and Other Intangible Assets.

RMM Acquisition

As of December 31, 2022, Williams owned a 50 percent interest in Rocky Mountain Midstream Holdings LLC (RMM) which it accounted for as an equity-method investment. On November 30, 2023, Williams closed on the acquisition of the remaining 50 percent interest in RMM (RMM Acquisition) for $704 million. As a result of acquiring this additional interest, Williams obtained control and subsequently consolidates RMM. The purpose of this acquisition was to expand Williams’ gathering and processing footprint and create operational synergies for its operations in the DJ Basin. Assets acquired and results of operations realized are included within Williams’ West segment. Substantially all of the RMM purchase price was not due to the seller until the first quarter of 2025, would not accrue interest until November 2, 2024, and could be repaid early without penalty. It was recorded as a deferred consideration obligation at fair value using an income approach, which resulted in a discount to the contractual amount due which was imputed as interest expense over the term of the obligation. On November 1, 2024, Williams paid the remaining $651 million of the RMM purchase price obligation.

During the period from the acquisition date of November 30, 2023 to December 31, 2023, RMM contributed Revenues of $53 million and Modified EBITDA of $12 million.

Williams accounted for the RMM Acquisition as a business combination. The book value of Williams’ existing equity-method investment prior to the acquisition date of November 30, 2023, was $406 million. Williams recognized a $30 million gain on remeasuring its existing equity-method investment to fair value included in Other investing income (loss) – net during the fourth quarter of 2023, which is not included in the pro forma DJ Basin adjustments below. The valuation techniques used consisted of the income approach for Williams’ previous equity-method investment in RMM and the valuation of other intangible assets, and the cost approach for property, plant, and equipment.


	(Millions)
Cash and cash equivalents	$	28
Other current assets	4
Investments	20
Property, plant, and equipment – net	1,041
Intangible assets – net	63
Other noncurrent assets	12
Total identifiable assets acquired	1,168

Current liabilities	(44)
Noncurrent liabilities	(103)
Total liabilities assumed	(147)

Net identifiable assets acquired	1,021

Goodwill included in Intangible assets – net	55
Net assets acquired	$	1,076

Goodwill recognized in the RMM Acquisition relates primarily to enhancing and diversifying Williams’ basin positions as well as delivering operational synergies, including increasing volumes on its existing processing facilities and increasing revenues on its NGL transportation, fractionation, and storage assets, and is reported within Williams’ West segment. Substantially all of the goodwill is deductible for tax purposes.

Other intangible assets recognized in the RMM Acquisition are related to contractual customer relationships from gas gathering and processing agreements with customers. The basis for determining the value of these intangible assets is estimated future net cash flows to be derived from acquired contractual customer relationships discounted using a risk-adjusted discount rate. These intangible assets are being amortized on a straight-line basis over an initial period of 20 years which represents the term over which the contractual customer relationships are expected to contribute to Williams’ cash flows. Approximately 18 percent of the expected future revenues from these contractual customer relationships are impacted by Williams’ ability and intent to renew or renegotiate existing customer contracts. Williams expenses costs incurred to renew or extend the terms of its gas gathering contracts with customers. Based on the estimated future revenues during the current contract periods (as estimated at the time of the acquisition), the weighted-average period prior to the next renewal or extension of the existing contractual customer relationships is approximately 10 years. See Note 11 – Goodwill and Other Intangible Assets.

MountainWest Acquisition

On February 14, 2023, Williams closed on the acquisition of 100 percent of MountainWest, which includes FERC-regulated interstate natural gas pipeline systems and natural gas storage capacity (MountainWest Acquisition), for $1.08 billion of cash, funded with available sources of short-term liquidity, and retaining $430 million outstanding principal amount of MountainWest long-term debt. For 2023, $1.024 billion is presented in Purchases of businesses, net of cash acquired reflecting the cash purchase price, reduced for post-closing adjustments and the cash acquired as presented in the purchase price allocation. The purpose of the MountainWest Acquisition was to expand Williams’ existing transmission and storage infrastructure footprint into major markets in Utah, Wyoming, and Colorado. Assets acquired, acquisition-related costs incurred, and results of operations realized are included within Williams’ Transmission, Power & Gulf segment.

During the period from the acquisition date of February 14, 2023 to December 31, 2023, the operations acquired in the MountainWest Acquisition contributed Revenues of $225 million and Modified EBITDA of $122 million, which includes $27 million of transition-related costs.

Acquisition-related costs for the MountainWest Acquisition total $18 million, including $16 million incurred in 2023, and are included in General and administrative expenses.

Williams accounted for the MountainWest Acquisition as a business combination. The valuation techniques used consisted of the cost approach for nonregulated property, plant, and equipment, as well as the market approach for the assumed long-term debt consistent with the valuation technique discussed in Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk. MountainWest’s regulated operations are accounted for pursuant to ASC 980. The fair value of assets and liabilities subject to rate making and cost recovery provisions were determined utilizing the income approach. MountainWest’s expected return on rate base is consistent with expected returns of similarly situated assets, resulting in carryover basis of these assets and liabilities equaling their fair value.


	(Millions)
Cash and cash equivalents	$	23
Trade accounts and other receivables	33
Other current assets	26
Investments	20
Property, plant, and equipment – net	1,019
Other noncurrent assets	33
Total identifiable assets acquired	1,154

Current liabilities	(47)
Long-term debt	(365)
Other noncurrent liabilities	(95)
Total liabilities assumed	(507)

Net identifiable assets acquired	647

Goodwill included in Intangible assets – net	400
Net assets acquired	$	1,047

Goodwill recognized in the MountainWest Acquisition relates primarily to enhancing and diversifying Williams’ basin positions and the long-term value associated with rate-regulated businesses and is reported within its Transmission, Power & Gulf segment. Substantially all of the goodwill is deductible for tax purposes.

Supplemental Pro Forma




















	Year Ended December 31, 2024
	As Reported		Pro Forma Crowheart (1)		Pro Forma Discovery (1)								Pro Forma Combined
	(Millions)
Revenues	$	10,503	$	60	$	58							$	10,621
Net income (loss) attributable to The Williams Companies, Inc.	2,225		8		(5)								2,228

	Year Ended December 31, 2023
	As Reported		Pro Forma Crowheart		Pro Forma Discovery		Pro Forma Gulf Coast Storage		Pro Forma DJ Basin (1)		Pro Forma MountainWest (1)		Pro Forma Combined
	(Millions)
Revenues	$	10,907	$	74	$	129	$	202	$	270	$	35	$	11,617
Net income (loss) attributable to The Williams Companies, Inc.	3,179		19		(1)		53		17		6		3,273

(1)Excludes results from operations acquired in the acquisition for the period beginning on the acquisition date, as these results are included in the amounts as reported.

Sale of South Mansfield Upstream Interests

In October 2025, Williams entered into an agreement to sell its interests in certain upstream ventures in the South Mansfield area of the Haynesville Shale region, included in upstream operations within Other, for consideration of $398 million with additional contingent consideration to possibly be received through 2029. Williams designated these operations as held for sale, with the associated assets and liabilities included in Assets held for sale and Liabilities held for sale, respectively, as of December 31, 2025. The transaction closed on January 30, 2026, and Williams expects to recognize a gain in the first quarter of 2026. The results of operations for this disposal group were not significant for the reporting periods.

Sale of Certain Gulf Coast Liquids Pipelines

On September 29, 2023, Williams completed the sale of various petrochemical and feedstock pipelines and associated contracts in the Gulf Coast region for $348 million. As a result of this sale, Williams recorded a gain of $129 million in 2023 in its Transmission, Power & Gulf segment. The gain is reflected in Gain on sale of business. The results of operations for this disposal group, excluding the gain noted, were not significant for the reporting periods.

Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Public Utilities General Disclosures

The FERC has prescribed a formula to be used in computing separate allowances for borrowed and equity AFUDC. These allowances are recorded as follows:

Transco


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Allowance for borrowed funds used during construction	$	7	$	17	$	14
Allowance for equity funds used during construction	28		71		63
Allowance for equity and borrowed funds used during construction (AFUDC)	$	35	$	88	$	77

NWP


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Allowance for borrowed funds used during construction	$	2	$	2	$	1
Allowance for equity funds used during construction	7		8		3
Allowance for equity and borrowed funds used during construction (AFUDC)	$	9	$	10	$	4

Related Party Transactions (Tables)

12 Months Ended

Dec. 31, 2025

Schedule of Related Party Transactions


	December 31,		December 31,
	2025		2024
	(Millions)
Advances to affiliate
Transco	$	954	$	638
NWP	218		—

Advances from affiliate

NWP	$	—	$	26


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Net interest income from advances
Transco		$	29	$	51	$	81
NWP		3		5		8


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Transco affiliate activity
Total revenues		$	86	$	76	$	56
Natural gas product costs		9		5		7


	Year Ended December 31,
		2025		2024		2023
		(Millions)
Services with affiliates
Transco		$	352	$	344	324
NWP		91		91		86

Credit Facility and Commercial Paper (Details)
$ in Millions

12 Months Ended

Oct. 08, 2021

USD ($)

Dec. 31, 2025

USD ($)

Dec. 01, 2025

Dec. 31, 2024

USD ($)

Credit Facility and Commercial Paper [Line Items]

Commercial paper, outstanding

$ 700

$ 455

Williams Companies Inc [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

$ 3,750

3,750

^[1]

Credit facility, loans outstanding

^[1]

$ 0

Additional amount by which credit facility can be increased

$ 500

Maximum ratio of debt to EBITDA after acquisition

5.5

Acquisition Trigger Amount

$ 25

Williams Companies Inc [Member] | Swing Line Loan [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

200

Williams Companies Inc [Member] | Commercial paper [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

3,500

Commercial paper, maximum maturity

397 days

Short-Term Debt, Weighted Average Interest Rate, at Point in Time

3.85%

Williams Companies Inc [Member] | Letters of credit [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

$ 500

Williams Companies Inc [Member] | Letters Of Credit Under Certain Bilateral Bank Agreements [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, letters of credit outstanding

$ 15

Transcontinental Gas Pipe Line Company, LLC [Member]

Credit Facility and Commercial Paper [Line Items]

Maximum ratio of debt to capitalization

65.00%

Transcontinental Gas Pipe Line Company, LLC [Member] | Letters of credit [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

$ 500

Northwest Pipeline LLC [Member]

Credit Facility and Commercial Paper [Line Items]

Maximum ratio of debt to capitalization

65.00%

Northwest Pipeline LLC [Member] | 7.125% Debentures Due 2025 [Member]

Credit Facility and Commercial Paper [Line Items]

Long-term debt

$ 0

Long-term debt interest rate

7.125%

Northwest Pipeline LLC [Member] | Variable rate Term Loan Due 2028

Credit Facility and Commercial Paper [Line Items]

Long-term debt

$ 250

$ 0

Northwest Pipeline LLC [Member] | Letters of credit [Member]

Credit Facility and Commercial Paper [Line Items]

Credit facility, capacity

$ 500

Dec21 And Subsequent Quarters [Member] | Williams Companies Inc [Member]

Credit Facility and Commercial Paper [Line Items]

Maximum ratio of debt to EBITDA

5.0

[1]	In managing its available liquidity, Williams does not expect a maximum outstanding amount in excess of the capacity of its credit facility inclusive of any outstanding amounts under the commercial paper program.

Consolidated Balance Sheet (Parenthetical) - Williams - USD ($) shares in Thousands, $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Accounts Receivable, Allowance for Credit Loss, Current	$ 1	$ 1
Common Stock, Par or Stated Value Per Share	$ 1	$ 1
Common Stock, Shares Authorized	1,470,000	1,470,000
Common Stock, Shares, Issued	1,261,000	1,258,000
Treasury Stock, Common, Shares	39,000	39,000
Series B Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share	$ 1	$ 1
Preferred Stock, Shares Authorized	30,000	30,000
Preferred Stock, Shares Issued	35	35

Fair Value Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance at beginning of period	$ 48	$ 53
Realized and unrealized gains (losses): Included in income (loss)	$ 50	$ (5)
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization	Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization
Purchases, issuances, and settlements	$ (31)	$ (1)
Transfers into Level 3	(78)	1
Transfers out of Level 3	(4)	0
Balance at end of period	$ (15)	$ 48

Debt and Banking Arrangements

12 Months Ended

Dec. 31, 2025

Debt Disclosure [Abstract]

Debt and Banking Arrangements [Text Block]

Note 13 – Debt and Banking Arrangements

Long-Term Debt by Issuing Entity


	December 31,
	2025		2024
	(Millions)
Transco:
7.080% Debentures due 2026	$	8	$	8
7.250% Debentures due 2026	200		200
7.850% Notes due 2026	—		1,000
4.000% Notes due 2028	400		400
3.250% Notes due 2030	700		700
5.100% Notes due 2036	1,000		—
5.400% Notes due 2041	375		375
4.450% Notes due 2042	400		400
4.600% Notes due 2048	600		600
3.950% Notes due 2050	500		500
5.750% Notes due 2056	700		—
Other financing obligation — Atlantic Sunrise	734		764
Other financing obligation — Leidy South	74		75
Other financing obligation — Dalton	247		247
Unamortized debt issuance costs	(35)		(23)
Net unamortized debt premium (discount)	(15)		(11)
Total debt — Transco	$	5,888	$	5,235
MountainWest:
3.530% Notes due 2028 (Note 3)	$	100	$	100
3.910% Notes due 2038 (Note 3)	150		150
4.875% Notes due 2041 (Note 3)	180		180
Net unamortized debt premium (discount)	(54)		(58)
Total debt — MountainWest	$	376	$	372
NWP:
7.125% Debentures due 2025	$	—	$	85
4.000% Notes due 2027	500		500
Term loan due 2028 (see NWP Credit Agreement)	250		—
Unamortized debt issuance costs	(1)		(1)
Net unamortized debt premium (discount)	(1)		(2)
Total debt — NWP	$	748	$	582
Williams:
3.900% Notes due 2025	$	—	$	750
4.000% Notes due 2025	—		750
5.400% Notes due 2026	1,100		1,100
7.700% Notes due 2027	2		2
3.750% Notes due 2027	1,450		1,450
5.300% Notes due 2028	900		900
4.900% Notes due 2029	1,100		1,100
4.800% Notes due 2029	450		450
4.625% Notes due 2030	750		—
3.500% Notes due 2030	1,000		1,000


	December 31,
	2025		2024
	(Millions)
2.600% Notes due 2031	$	1,500	$	1,500
7.500% Debentures due 2031	339		339
7.750% Notes due 2031	252		252
8.750% Notes due 2032	445		445
4.650% Notes due 2032	1,000		1,000
5.650% Notes due 2033	750		750
5.150% Notes due 2034	1,300		1,300
5.300% Notes due 2035	750		—
5.600% Notes due 2035	1,000		—
6.300% Notes due 2040	1,250		1,250
5.800% Notes due 2043	400		400
5.400% Notes due 2044	500		500
5.750% Notes due 2044	650		650
4.900% Notes due 2045	500		500
5.100% Notes due 2045	1,000		1,000
4.850% Notes due 2048	800		800
3.500% Notes due 2051	650		650
5.300% Notes due 2052	750		750
5.800% Notes due 2054	750		750
6.000% Notes due 2055	500		—

Unamortized debt issuance costs	(142)		(130)
Net unamortized debt premium (discount)	(47)		(41)
Total debt — Williams	$	21,649	$	20,167
Gulf Coast Storage deferred consideration obligation (Note 3)	—		100
Total debt	$	28,661	$	26,456
Long-term debt due within one year — Williams	(1,099)		(1,600)
Long-term debt due within one year — Transco	(246)		(35)
Long-term debt due within one year — NWP	—		(85)
Long-term debt	$	27,316	$	24,736

Certain of Williams’ debt agreements contain covenants that restrict or limit, among other things, its ability to create liens supporting indebtedness, sell assets, and incur additional debt. Default of these agreements could also restrict Williams’ ability to make certain distributions or repurchase equity.


	December 31, 2025
	(Millions)
Williams:
2026	$	1,345
2027	1,994
2028	1,696
2029	1,600
2030	2,504

Transco:
2026	$	246
2027	42
2028	446
2029	50
2030	754

NWP:
2027	$	500
2028	250

Issuances

Senior unsecured debt issuances for the past three years and subsequent to the balance sheet date are as follows:


Issue Date	Maturity Date	Amount		Rate
		(Millions)
Williams Public Issuances:
January 8, 2026 (1)	March 15, 2033	$	500	5.650%
January 8, 2026	March 15, 2036	1,250		5.150%
January 8, 2026	March 15, 2056	1,000		5.950%
June 30, 2025	June 30, 2030	750		4.625%
June 30, 2025	September 30, 2035	750		5.300%
January 9, 2025	March 15, 2035	1,000		5.600%
January 9, 2025	March 15, 2055	500		6.000%
August 13, 2024	November 15, 2029	450		4.800%
August 13, 2024 (2)	March 15, 2034	300		5.150%
August 13, 2024	November 15, 2054	750		5.800%
January 5, 2024	March 15, 2029	1,100		4.900%
January 5, 2024	March 15, 2034	1,000		5.150%
August 10, 2023 (3)	March 2, 2026	350		5.400%
August 10, 2023	August 15, 2028	900		5.300%
March 2, 2023	March 2, 2026	750		5.400%
March 2, 2023	March 15, 2033	750		5.650%
Transco Private Placements:
November 20, 2025 (4)	March 15, 2036	$	1,000	5.100%
November 20, 2025 (4)	March 15, 2056	700		5.750%

________________

(1) Additional issuance of the 5.65 percent senior notes due 2033 issued on March 2, 2023, and trade interchangeably with such notes.

(2) Additional issuance of the 5.15 percent senior notes due 2034 issued on January 5, 2024, and trade interchangeably with such notes.

(3) Additional issuance of the 5.40 percent senior notes due 2026 issued on March 2, 2023, and trade interchangeably with such notes.

Retirements

Senior unsecured public debt retirements for the past three years are as follows:


Date of Retirement	Maturity Date	Amount		Rate
		(Millions)
Williams:
September 15, 2025	September 15, 2025	$	750	4.000%
January 15, 2025	January 15, 2025	750		3.900%
June 4, 2024	June 4, 2024	1,250		4.550%
March 4, 2024	March 4, 2024	1,000		4.300%
November 15, 2023	November 15, 2023	600		4.500%
Transco:
December 5, 2025	February 1, 2026	$	1,000	7.850%
NWP:
December 1, 2025	December 1, 2025	$	85	7.125%

Other financing obligations

During the construction of the Atlantic Sunrise, Leidy South, and Dalton projects, Transco received funding from co-owners for their proportionate share of construction costs. Amounts received were recorded within noncurrent liabilities and the costs associated with construction were capitalized. Upon placing these projects into service Transco began utilizing the co-owners’ undivided interest in the assets, including the associated pipeline capacity, and reclassified the funding previously received from its co-owners from noncurrent liabilities to debt. The obligations, which mature in 2038, 2041, and 2052, respectively, require monthly interest and principal payments and bear interest rates of approximately 9 percent, 13 percent, and 9 percent, respectively.

Credit Facility


	December 31, 2025
	Stated Capacity		Outstanding
	(Millions)
Long-term credit facility (1)	$	3,750	$	—
Letters of credit under certain bilateral bank agreements			15

________________

Revolving credit facility

Williams, along with Transco and NWP, is party to an amended and restated revolving credit agreement (Williams Credit Agreement) with the lenders named therein and the administrative agent that provides for aggregate commitments of up to $3.75 billion, with the ability to increase such commitments by up to an additional $500 million under certain circumstances. The credit facility currently matures on October 8, 2028, following a one‑year extension exercised in the second quarter of 2025, and permits an additional one‑year maturity extension, subject to specified conditions. Borrowings under the credit facility bear interest based on either an alternative base rate or Term Secured Overnight Financing Rate, in each case plus an applicable margin. The facility also permits swing line loans of up to $200 million and letters of credit commitments of up to $500 million. Transco and NWP are each able to borrow up to $500 million under the facility, subject to availability.

The Williams Credit Agreement contains the following terms and conditions:

•Various covenants may limit, among other things, a borrower’s and its material subsidiaries’ ability to grant certain liens supporting indebtedness, merge or consolidate, sell all or substantially all of its assets in certain circumstances, make certain distributions during an event of default, and each borrower and each borrower’s respective material subsidiaries’ ability to enter into certain restrictive agreements.

•If an event of default with respect to a borrower occurs under the credit facility, the lenders will be able to terminate the commitments for the respective borrowers and accelerate the maturity of the loans of the defaulting borrower under the credit facility and exercise other rights and remedies.

•Other than swing line loans, each time funds are borrowed, the applicable borrower may choose from two methods of calculating interest: a fluctuating base rate equal to an alternative base rate as defined in the Williams Credit Agreement plus an applicable margin or a periodic fixed rate equal to the Term Secured Overnight Financing Rate plus an applicable margin. Williams is required to pay a commitment fee based on the unused portion of the credit facility. The applicable margin is determined by reference to a pricing schedule based on the applicable borrower’s senior unsecured long-term debt ratings and the commitment fee is determined by reference to a pricing schedule based on Williams’ senior unsecured long-term debt ratings.

Significant financial covenants under the Williams Credit Agreement require Williams’ ratio of debt to EBITDA (earnings before interest, taxes, depreciation, and amortization), each as defined in the Williams Credit Agreement, to be no greater than 5.0 to 1.0, except that for any fiscal quarter in which the funding of the purchase price for an acquisition (whether effectuated as one or a series of related transactions) with an aggregate purchase price of $25 million or more has been effected, and the following two fiscal quarters (in each case subject to certain limitations), the ratio of debt to EBITDA is to be no greater than 5.5 to 1.

The ratio of debt to capitalization (defined as net worth plus debt), each as defined in the Williams Credit Agreement, must be no greater than 65 percent for each of Transco and NWP.

Williams expects to be in compliance with these covenants for the December 31, 2025, reporting period.

Commercial Paper Program

Williams has a $3.5 billion commercial paper program. The maturities of the commercial paper notes vary but may not exceed 397 days from the date of issuance. The commercial paper notes are sold under customary terms in the commercial paper market and are issued at a discount from par, or, alternatively, are sold at par and bear varying interest rates on a fixed or floating basis. The net proceeds of issuances of the commercial paper notes are expected to be used to fund planned capital expenditures and for other general corporate purposes. At December 31, 2025, $700 million of commercial paper was outstanding at a weighted-average interest rate of 3.85 percent.

NWP Credit Agreement

In December 2025, NWP, the lenders named therein, and an administrative agent entered into a credit agreement (NWP Credit Agreement). The NWP Credit Agreement was effective on December 1, 2025, and NWP borrowed $250 million under a three-year term loan used to refinance its 7.125 percent debentures due December 1, 2025, and for working capital, acquisitions, capital expenditures and other general corporate or limited liability company purposes.

The NWP Credit Agreement contains the following terms and conditions:

•Various covenants may limit, among other things, NWP’s ability to grant certain liens supporting indebtedness, merge or consolidate, sell all or substantially all of its assets in certain circumstances, make certain distributions during an event of default, and ability to enter into certain restrictive agreements.

•If an event of default the lenders will be able to accelerate the maturity of the loans under the NWP credit facility and exercise other rights and remedies.

•Interest on borrowings under the NWP Credit Agreement is variable.

•NWP is required to maintain a ratio of debt to capitalization (defined as net worth plus debt) of no greater than 65 percent. This ratio will be tested at the end of each fiscal quarter.

Restrictive Debt Covenants

At December 31, 2025, none of Transco’s nor NWP’s debt instruments restrict the amount of distributions to Williams, provided, however, that under the Williams Credit Agreement described above, Transco or NWP are restricted from making distributions to Williams during an event of default if Transco or NWP have directly incurred indebtedness under the credit facility. The debt agreements of Transco and NWP contain restrictions on their ability to incur secured debt beyond certain levels and to guarantee certain indebtedness. Transco and NWP expect to be in compliance with these covenants, for the December 31, 2025 reporting period.

Cash Payments for Interest by Registrant (Net of Amounts Capitalized)


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Williams	$	1,404	$	1,293	$	1,152
Transco	336		302		307
NWP	24		24		26

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481544/470-10-50-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477092/405-40-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
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+ Details

Description of Business and Basis of Presentation (Details) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Sep. 03, 2021

General and Description Of Business [Abstract]

Stock Repurchase Program, Authorized Amount

$ 1,500

Purchases of treasury stock

$ 0

$ 130

Stock Repurchase Program Cumulative Amount Purchased

139

Loss Contingencies [Line Items]

Proceeds from Legal Settlements

627

$ 0

$ 534

^[1]

Gulfstream Natural Gas System, LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

Blue Racer Midstream LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

Overland Pass Pipeline Company LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

Transmission, Power & Gulf [Member] | Gulfstream Natural Gas System, LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

Transmission, Power & Gulf [Member] | Discovery Producer Services LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

60.00%

Northeast G & P [Member] | Blue Racer Midstream LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

Northeast G & P [Member] | Williams Companies Inc [Member] | Northeast JV [Member] | Variable Interest Entity, Primary Beneficiary [Member]

General and Description Of Business [Abstract]

Variable Interest Entity Ownership Percentage

65.00%

Northeast G & P [Member] | Williams Companies Inc [Member] | Cardinal Gas Services LLC [Member] | Variable Interest Entity, Primary Beneficiary [Member]

General and Description Of Business [Abstract]

Variable Interest Entity Ownership Percentage

66.00%

Northeast G & P [Member] | Williams Companies Inc [Member] | Appalachia Midstream Services, LLC [Member]

General and Description Of Business [Abstract]

Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest

66.00%

West [Member] | Overland Pass Pipeline Company LLC [Member]

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

50.00%

West [Member] | Williams Companies Inc [Member] | Conway Fractionator [Member]

General and Description Of Business [Abstract]

Subsidiary of Limited Liability Company or Limited Partnership, Ownership Interest

50.00%

Gas & NGL Marketing Services | Cogentrix Co-Investment Fund, LP | Indirect Ownership Interest

General and Description Of Business [Abstract]

Equity Method Investment, Ownership Percentage

10.00%

Former Alaska Refinery [Member]

Loss Contingencies [Line Items]

Loss Contingency Accrual, Period Increase (Decrease)

$ 125

[1]	Net gain from Energy Transfer litigation judgment resulted from a favorable ruling in November 2023 (Note 1 – Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies).

Fair Value Measurements Concentration of Credit Risk (Details) - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2025

Dec. 31, 2024

Dec. 31, 2023

Concentration Risk [Line Items]

Receivables, Net, Current

$ 2,084

$ 1,863

Revenues

11,950

10,503

$ 10,907

Transcontinental Gas Pipe Line Company, LLC [Member]

Concentration Risk [Line Items]

Revenues

3,263

2,964

2,866

Transcontinental Gas Pipe Line Company, LLC [Member] | Dominion Energy, Inc

Concentration Risk [Line Items]

Revenues

216

^[1]

217

^[1]

287

Northwest Pipeline LLC [Member]

Concentration Risk [Line Items]

Revenues

458

444

440

Northwest Pipeline LLC [Member] | Puget Sound Energy, Inc

Concentration Risk [Line Items]

Revenues

139

136

126

Northwest Pipeline LLC [Member] | Northwest Natural Gas Company

Concentration Risk [Line Items]

Revenues

Northwest Pipeline LLC [Member] | Cascade Natural Gas Corporation

Concentration Risk [Line Items]

Revenues

$ 47

NGLs, natural gas, and related products and services [Member]

Concentration Risk [Line Items]

Receivables, Net, Current

575

594

Transportation of natural gas and related products [Member]

Concentration Risk [Line Items]

Receivables, Net, Current

404

339

Marketing Of Natural Gas And NGLs

Concentration Risk [Line Items]

Receivables, Net, Current

535

516

Oil and Gas, Exploration and Production

Concentration Risk [Line Items]

Receivables, Net, Current

Accounts Receivable related to revenues from contracts with customers [Member]

Concentration Risk [Line Items]

Receivables, Net, Current

1,532

1,494

Derivative Receivables

Concentration Risk [Line Items]

Receivables, Net, Current

444

294

Other Receivable [Member]

Concentration Risk [Line Items]

Receivables, Net, Current

$ 108

$ 75

[1]	The 2025 and 2024 amounts are less than 10 percent of Transco’s revenue

Fair Value Measurements, Guarantees, and Concentration of Credit Risk (Tables)

12 Months Ended

Dec. 31, 2025

Fair Value Disclosures [Abstract]

Fair Value Assets and Liabilities Measured On Recurring Basis [Table Text Block]

The following table presents, by level within the fair value hierarchy, certain of Williams’, Transco’s, and NWP’s significant financial assets and liabilities. The carrying values of cash and cash equivalents, accounts receivable, accounts payable, and commercial paper approximate fair value because of the short-term nature of these instruments. Therefore, these assets and liabilities are not presented in the following table.


					Fair Value Measurements Using
	Carrying Amount		Fair Value		Quoted Prices In Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(Millions)
Assets (liabilities) at December 31, 2025:
Measured on a recurring basis:
ARO Trust - Transco	$	356	$	356	$	356	$	—	$	—
Commodity derivative assets (1)	336		722		431		158		133
Commodity derivative liabilities (1)	(340)		(915)		(497)		(270)		(148)


Additional disclosures:


Guarantees	(35)		(28)		—		(12)		(16)
Debt by issuer, including current portion:
Williams	(21,649)		(21,556)		—		(21,556)		—
Transco	(5,888)		(5,941)		—		(5,941)		—
NWP	(748)		(747)		—		(747)		—
MountainWest	(376)		(385)		—		(385)		—
Total debt	(28,661)		(28,629)		—		(28,629)		—

Assets (liabilities) at December 31, 2024:
Measured on a recurring basis:
ARO Trust - Transco	$	297	$	297	$	297	$	—	$	—
Commodity derivative assets (1)	344		726		427		188		111
Commodity derivative liabilities (1)	(400)		(1,070)		(532)		(475)		(63)

Additional disclosures:

Guarantees	(36)		(28)		—		(12)		(16)
Debt by issuer, including current portion:
Williams	(20,167)		(19,517)		—		(19,517)		—
Transco	(5,235)		(5,276)		—		(5,276)		—
NWP	(582)		(573)		—		(573)		—
MountainWest	(372)		(364)		—		(364)		—
Gulf Coast Storage deferred consideration (Note 3)	(100)		(100)		—		(100)		—
Total debt	(26,456)		(25,830)		—		(25,830)		—

(1)The carrying amount is presented net of counterparty offsetting arrangements and collateral (see Note 17 – Commodity Derivatives).

Debt Securities, Trading, and Equity Securities, FV-NI

Investments within the ARO Trust were as follows:


	December 31, 2025				December 31, 2024
	Amortized Cost Basis		Fair Value		Amortized Cost Basis		Fair Value
	(Millions)
Money market fund	$	34	$	34	$	27	$	27
U.S. equity funds	53		169		53		146
International equity fund	32		51		32		40
Municipal bond fund	104		102		88		84
Total	$	223	$	356	$	200	$	297

Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation

The following table presents a reconciliation of changes in fair value of the net commodity derivatives classified as Level 3 in the fair value hierarchy.




	Year Ended December 31,
	2025		2024
	(Millions)
Balance at beginning of period	$	48	$	53
Gains (losses) included in Williams’ Consolidated Statement of Income	50		(5)
Purchases, issuances, and settlements	(31)		(1)
Transfers into Level 3	(78)		1
Transfers out of Level 3	(4)		—
Balance at end of period	$	(15)	$	48

Contract With Customer Accounts Receivable

The following table summarizes Williams’ concentration of receivables, net of allowances:


	December 31,
	2025		2024
	(Millions)
Natural gas, NGLs, and related products and services	$	575	$	594
Regulated interstate natural gas transportation and storage	404		339
Marketing of natural gas and NGLs	535		516
Upstream activities	18		45
Accounts receivable related to revenues from contracts with customers	1,532		1,494
Receivables from derivatives	444		294
Other accounts receivable	108		75
Trade accounts and other receivables - net	$	2,084	$	1,863

Fair Value, Concentration of Risk

Customers representing 10 percent or more of Transco’s and NWP’s revenues include:


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Transco:
Dominion Energy, Inc (1)	$	216	$	217	$	287

NWP:
Puget Sound Energy, Inc.	$	139	$	136	$	126
Northwest Natural Gas Company	49		47		47
Cascade Natural Gas Corporation	48		46		47

_______________

(1) The 2025 and 2024 amounts are less than 10 percent of Transco’s revenue.

- Definition

Tabular disclosure of all significant concentrations of risk, including credit risk and market risk, arising from all financial instruments (as defined), whether from an individual counterparty or groups of counterparties. The disclosure concerning concentrations of risk may consist of the following information: (1) for concentrations of credit risk disclosure may include: (a) information about the (shared) activity, region, or economic characteristic that identifies the concentration, (b) the maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity, (c) the policy of requiring collateral or other security to support financial instruments subject to credit risk, information about the entity's access to that collateral or other security, and the nature and a brief description of the collateral or other security supporting those financial instruments, and (d) the policy of entering into master netting arrangements to mitigate the credit risk of financial instruments, information about the arrangements for which the entity is a party, and a brief description of the terms of those arrangements, including the extent to which they would reduce the entity's maximum amount of loss due to credit risk and (2) for disclosure of quantitative information about the market risks of financial instruments that is consistent with the way the company manages or adjusts those risks, disclosure may include: (a) more details about current positions and perhaps activity during the period, (b) the hypothetical effects on comprehensive income (or net assets), or annual income, of several possible changes in market prices, (c) a gap analysis of interest rate re-pricing or maturity dates, (d) the duration of the financial instruments, (e) the entity's value at risk from derivatives and from other positions at the end of the reporting period and the average value at risk during the year, or (f) other ways of reporting quantitative information as internally developed.

+ References + Details

Variable Interest Entities

12 Months Ended

Dec. 31, 2025

Variable Interest Entity Disclosures [Abstract]

Variable Interest Entities [Text Block]

Note 2 – Variable Interest Entities.

Consolidated VIEs

As of December 31, 2025, Williams consolidated the following VIEs:

Northeast JV

Williams owns a 65 percent interest in the Northeast JV, a subsidiary that is a VIE due to certain voting rights being disproportionate to the obligation to absorb losses and substantially all of the Northeast JV’s activities being performed on Williams’ behalf. Williams is the primary beneficiary because it has the power to direct the activities that most significantly impact the Northeast JV’s economic performance. The Northeast JV provides midstream services for producers in the Marcellus Shale and Utica Shale regions. Future expansion activity is expected to be funded with capital contributions from Williams and the other equity partner on a proportional basis.

Cardinal

Williams owns a 66 percent interest in Cardinal, a subsidiary that provides gathering services for the Utica Shale region and is a VIE due to certain risks shared with customers. Williams is the primary beneficiary because it has the power to direct the activities that most significantly impact Cardinal’s economic performance. Future expansion activity is expected to be funded with capital contributions from Williams and the other equity partner on a proportional basis.

Driftwood Pipeline

Williams owns an 80 percent interest in Driftwood Pipeline LLC (Driftwood Pipeline), a subsidiary that is a VIE because completion of the Driftwood Pipeline will require additional subordinated financial support from its equity holders in the form of capital contributions. Williams is the primary beneficiary because it has the power to direct the activities that most significantly impact Driftwood Pipeline’s economic performance. Williams, as the operator of Driftwood Pipeline, is responsible for constructing the proposed Driftwood Pipeline, Line 200, that will supply gas to Louisiana LNG's liquid natural gas (LNG) export facility near Lake Charles, Louisiana. The total remaining cost of the project would be funded with capital contributions from Williams and the other equity partners on a proportional basis.

The following table presents amounts included in the Consolidated Balance Sheet that are only for the use or obligation of the consolidated VIEs:


	December 31,

	2025		2024 (1)
	(Millions)
Assets (liabilities):
Cash and cash equivalents	$	53	$	15
Trade accounts and other receivables	155		178
Inventories	6		5
Other current assets and deferred charges	5		7
Property, plant, and equipment – net	4,412		4,896
Intangible assets – net	1,831		1,940
Regulatory assets, deferred charges, and other	23		27
Accounts payable	(56)		(57)
Other current liabilities	(19)		(29)

Regulatory liabilities, deferred income, and other	(78)		(263)

__________

(1) 2024 includes amounts related to Gulfstar One LLC (Gulfstar One), which was a consolidated VIE at December 31, 2024. Williams acquired the remaining interest in Gulfstar One during the fourth quarter of 2025 and it is no longer a VIE. This transaction decreased Noncontrolling interests in consolidated subsidiaries by $166 million, increased Capital in excess of par value by $126 million, and increased Deferred income tax liabilities by $40 million in the Consolidated Balance Sheet.

Nonconsolidated VIEs

Williams owns certain equity-method investments that are VIEs due primarily to its limited participating rights as a minority equity holder. Williams’ maximum exposure to loss is limited to the carrying value of these investments (included within Investments in the Consolidated Balance Sheet), which totaled $611 million at December 31, 2025. Included in this total is Williams’ investment in Louisiana LNG and Cogentrix (discussed below).

Louisiana LNG

Williams owns a 10 percent interest in Louisiana LNG LLC (Louisiana LNG), which is a VIE because completion of the LNG facilities will require additional subordinated financial support from its equity holders in the form of capital contributions. At December 31, 2025, the carrying value of our investment in Louisiana LNG was $253 million. Our maximum exposure to loss is limited to the carrying value of our investment. The total remaining cost of the project would be funded with capital contributions from Williams and the other equity partners on a proportional basis.

Cogentrix

Williams owns a minority interest in Cogentrix, which is a VIE due primarily to our limited participation rights to direct Cogentrix’s activities. At December 31, 2025, the carrying value of our investment in Cogentrix was $292 million. Our maximum exposure to loss is limited to the carrying value of our investment. See Note 8 – Investing Activities for further discussion.

Leases (Tables)

12 Months Ended

Dec. 31, 2025

Leases [Abstract]

Lease, Cost [Table Text Block]

Williams


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	39	$	39	$	38
Variable lease cost	33		31		31
Sublease income	—		—		(1)
Total lease cost	$	72	$	70	$	68
Cash paid for operating lease liabilities	$	40	$	37	$	37


	December 31,
	2025		2024
	(Dollars in Millions)
Other Information:
Right-of-use assets (included in Regulatory assets, deferred charges, and other)	$	170	$	154
Operating lease liabilities:
Current (included in Other current liabilities)	$	32	$	26
Noncurrent (included in Regulatory liabilities, deferred income, and other)	$	151	$	142
Weighted-average remaining lease term – operating leases (years)	10		11
Weighted-average discount rate – operating leases	4.99%		4.90%

Transco


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	11	$	9	$	9
Variable lease cost	7		7		7
Total lease cost	$	18	$	16	$	16
Cash paid for operating lease liabilities	$	12	$	9	$	10

			December 31,
			2025		2024
			(Dollars in Millions)
Other Information:
Right-of-use assets (included in Deferred charges and other in Transco’s Balance Sheet)			$	64	$	48
Operating lease liabilities:
Current (included in Other current liabilities in Transco’s Balance Sheet)			$	9	$	6
Noncurrent (included in Deferred income and other in Transco’s Balance Sheet)			$	63	$	51
Weighted-average remaining lease term – operating leases (years)			12		13
Weighted-average discount rate – operating leases			4.84%		4.77%

NWP


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Lease Cost:
Operating lease cost	$	1	$	3		$	1
Variable lease cost	—		1			1
Total lease cost	$	1	$	4		$	2
Cash paid for operating lease liabilities	$	1	$	2		$	1

			December 31,
			2025			2024
			(Dollars in Millions)
Other Information:
Right-of-use assets (included in Deferred charges and other in NWP’s Balance Sheet)			$	4		$	5
Operating lease liabilities:
Current (included in Other current liabilities in NWP’s Balance Sheet)			$	—		$	1
Noncurrent (included in Deferred income and other in NWP’s Balance Sheet)			$	4		$	5
Weighted-average remaining lease term – operating leases (years)			18			19
Weighted-average discount rate – operating leases			4.66%			4.90%

Lessee, Operating Lease, Liability, Maturity [Table Text Block]


	(Millions)
2026	$	40
2027	36
2028	28
2029	25
2030	21
Thereafter	87
Total future lease payments	237
Less: Amount representing interest	54
Total obligations under operating leases	$	183


	(Millions)
2026	$	12
2027	13
2028	12
2029	13
2030	12
Thereafter	36
Total future lease payments	98
Less: Amount representing interest	26
Total obligations under operating leases	$	72


	(Millions)
2026	$	—
2027	1
2028	—
2029	1
2030	—
Thereafter	4
Total future lease payments	6
Less: Amount representing interest	2
Total obligations under operating leases	$	4

Subsequent Event	12 Months Ended
Subsequent Event	Dec. 31, 2025
Subsequent Events [Abstract]
Subsequent Event [Text Block]	Note 20 – Subsequent Event Quarterly Dividends to Common Stockholders On January 27, 2026, Williams’ board of directors approved a regular quarterly dividend to common stockholders of $0.525 per share payable on March 30, 2026.

Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Sep. 03, 2021
Retirement Benefits, Description [Abstract]
Threshold For Amortization Of Unrecognized Actuarial Gains Losses	10.00%
Share Repurchase Program [Abstract]
Stock Repurchase Program, Authorized Amount				$ 1,500
Purchases of treasury stock	$ 0	$ 0	$ 130
Stock Repurchase Program Cumulative Amount Purchased	139
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Retirement Benefits, Description [Abstract]
AOCI Including Portion Attributable to Noncontrolling Interest, before Tax	$ 105	55
Pension Benefits [Member]
Retirement Benefits, Description [Abstract]
Approximate Amortization Period Of Net Actuarial Gain Loss	9 years
Amortization Period Of Difference Between Expected And Actual Return On Plan Assets	5 years
Other Postretirement Benefits [Member]
Retirement Benefits, Description [Abstract]
Approximate Amortization Period Of Net Actuarial Gain Loss	3 years
Minimum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	1 year
Minimum [Member] \| Pension Benefits [Member]
Retirement Benefits, Description [Abstract]
Threshold For Market Related Value	90.00%
Maximum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	20 years
Maximum [Member] \| Pension Benefits [Member]
Retirement Benefits, Description [Abstract]
Threshold For Market Related Value	110.00%
Transcontinental Gas Pipe Line Company, LLC [Member]
Regulated Operations [Abstract]
Public Utilities, Allowance For Funds Used During Construction, Capitalized Cost of Debt	$ 7	17	14
Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity	28	71	63
Public Utilities, Allowance for Funds Used During Construction, Additions	$ 35	88	77
Transcontinental Gas Pipe Line Company, LLC [Member] \| Minimum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	1 year
Transcontinental Gas Pipe Line Company, LLC [Member] \| Maximum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	30 years
Northwest Pipeline LLC [Member]
Regulated Operations [Abstract]
Public Utilities, Allowance For Funds Used During Construction, Capitalized Cost of Debt	$ 2	2	1
Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity	7	8	3
Public Utilities, Allowance for Funds Used During Construction, Additions	$ 9	$ 10	$ 4
Northwest Pipeline LLC [Member] \| Minimum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	1 year
Northwest Pipeline LLC [Member] \| Maximum [Member]
Leases [Abstract]
Lessee, Operating Lease, Term of Contract	30 years

Related Party Transactions - Transco and NWP (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Related Party Transaction [Line Items]
Regulatory Liabilities	$ 1,319	$ 1,385
Employer's contributions charged to expense under defined contribution plan	74	69	$ 60
Accounts payable	$ 2,224	1,613
Related Party Transaction, Rate	4.00%
Revenues	$ 11,950	10,503	10,907
Transcontinental Gas Pipe Line Company, LLC [Member]
Related Party Transaction [Line Items]
Regulatory Liabilities	1,007	1,034
Employer's contributions charged to expense under defined contribution plan	14	13	12
Equity-based compensation expense	7	6	6
Interest Income, Other	37	58	87
Revenues	3,263	2,964	2,866
Cash distributions to parent	1,340	1,145	1,220
Transcontinental Gas Pipe Line Company, LLC [Member] \| Affiliated Entity
Related Party Transaction [Line Items]
Interest Income, Other	29	51	81
Revenues	86	76	56
Related Party Transaction, Purchases from Related Party	9	5	7
Operating Expenses	352	344	324
Transcontinental Gas Pipe Line Company, LLC [Member] \| Related Party
Related Party Transaction [Line Items]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current	954	638
Accounts payable	62	55
Transcontinental Gas Pipe Line Company, LLC [Member] \| Pension Benefits [Member]
Related Party Transaction [Line Items]
Pension Cost (Reversal of Cost)	1	1	2
Transcontinental Gas Pipe Line Company, LLC [Member] \| Other Postretirement Benefits [Member]
Related Party Transaction [Line Items]
Other Postretirement Benefits Cost (Reversal of Cost)	10	8	6
Northwest Pipeline LLC [Member]
Related Party Transaction [Line Items]
Regulatory Liabilities	245	253
Employer's contributions charged to expense under defined contribution plan	3	3	3
Equity-based compensation expense	2	2	2
Revenues	458	444	440
Cash distributions to parent	148	150	155
Northwest Pipeline LLC [Member] \| Affiliated Entity
Related Party Transaction [Line Items]
Accounts payable	0	26
Interest Income, Other	3	5	8
Operating Expenses	91	91	86
Northwest Pipeline LLC [Member] \| Related Party
Related Party Transaction [Line Items]
Accounts and Financing Receivable, after Allowance for Credit Loss, Current	218	0
Accounts payable	12	12
Northwest Pipeline LLC [Member] \| Pension Benefits [Member]
Related Party Transaction [Line Items]
Pension Cost (Reversal of Cost)	1	1	0
Northwest Pipeline LLC [Member] \| Other Postretirement Benefits [Member]
Related Party Transaction [Line Items]
Other Postretirement Benefits Cost (Reversal of Cost)	$ 1	$ 1	$ 0

Contingencies and Commitments	12 Months Ended
Contingencies and Commitments	Dec. 31, 2025
Commitments and Contingencies Disclosure [Abstract]
Contingencies and Commitments [Text Block]	Note 18 – Contingencies and Commitments Royalty Matters Certain customers, including Expand Energy Corporation (formerly Chesapeake Energy Corporation or Chesapeake), have been named in various lawsuits alleging underpayment of royalties and claiming, among other things, violations of anti-trust laws and the Racketeer Influenced and Corrupt Organizations Act. Williams has also been named as a defendant in certain of these cases filed in Pennsylvania based on allegations that Williams improperly participated with Chesapeake in causing the alleged royalty underpayments. Williams believes that the claims asserted are subject to indemnity obligations owed to Williams by Chesapeake, which obligations survived Chesapeake’s bankruptcy proceedings. Prior to its bankruptcy, Chesapeake reached a settlement to resolve substantially all Pennsylvania royalty cases pending. During the pendency of the bankruptcy, that settlement was renegotiated. The settlement applied to both Chesapeake and Williams and did not require any contribution from Williams. On August 23, 2021, after referral to the United States District Court for the Southern District of Texas by the bankruptcy court, the court approved the settlement. Two objectors filed an appeal with the United States Court of Appeals for the Fifth Circuit. On June 8, 2023, the Court of Appeals vacated the settlement approval and remanded to the United States District Court for the Southern District of Texas with instructions to dismiss the settlement proceedings for lack of jurisdiction. On August 31, 2023, the bankruptcy court entered an order finding the settlement agreements to be null and void. Certain plaintiffs filed a notice of dismissal of their claims against Chesapeake that arose prior to February 8, 2021, in the United States District Court for the Middle District of Pennsylvania lawsuits. The notice stated that plaintiffs are not releasing their claims against the other defendants, including Williams, or claims against Chesapeake that arose after February 9, 2021. Chesapeake has been dismissed from the lawsuits. Williams continues to believe the claims against Williams are subject to indemnity obligations owed to Williams by Chesapeake. Rate Matters On August 30, 2024, Transco filed a general rate case with the FERC for an overall increase in rates and to comply with the terms of the settlement of its prior rate case. On September 30, 2024, the FERC issued an order accepting and suspending Transco’s general rate filing to be effective March 1, 2025, subject to refund and the outcome of hearing procedures established by the FERC. The order also accepted rate decreases for certain services to be effective as of October 1, 2024. During the third quarter of 2025, Transco reached an agreement in principle with its customers and the other participants to settle all aspects of the rate case and has accrued a related liability for rate refunds. Transco filed with the FERC in October 2025 for approval of the settlement. On December 30, 2025, the FERC approved the settlement which will become effective March 1, 2026. Construction Litigation In February 2025, Transco received an adverse judgment related to litigation in the United States Bankruptcy Court for the District of Delaware involving a contractor that performed construction services for Transco’s Atlantic Sunrise project, which was completed in 2018. The total award to a contractor, estimated at $110 million, included amounts for unpaid invoices, interest, and attorney fees. During the fourth quarter of 2025, Transco reached an agreement in principle with the contractor to settle all aspects of the case. Transco has accrued a related liability, capitalizing the amount of the settlement in principle. Transco expects to recover approximately 29 percent of the settlement amount paid from the co-owner of the project. Environmental Matters The U.S. Environmental Protection Agency (EPA), other federal agencies, and various state regulatory agencies routinely propose and promulgate new rules, issue updated guidance to rules, or revise existing rules. These rulemakings include, but are not limited to, reviews and updates to the National Ambient Air Quality Standards, and promulgation of rules for new and existing source performance standards for certain equipment emitting volatile organic compounds and methane as well as limitations on emissions of greenhouse gas compounds. Regulatory changes are continuously monitored including how they may impact operations. Implementation of new or revised regulations may result in impacts to operations and increase the cost of additions to Property, plant, and equipment – net for both new and existing facilities in affected areas; however, due to regulatory uncertainty on final rule content or guidance and applicability timeframes, the cost of these regulatory impacts is not known at this time. Williams Williams is a participant in certain environmental activities in various stages including assessment studies, cleanup operations, and/or remedial processes at certain sites, some of which Williams currently does not own. Williams is monitoring these sites in a coordinated effort with other potentially responsible parties, the EPA, or other governmental authorities. Williams is jointly and severally liable along with unrelated third parties in some of these activities and solely responsible in others. Certain of Williams’ subsidiaries have been identified as potentially responsible parties at various Superfund and state waste disposal sites. In addition, these subsidiaries have incurred, or are alleged to have incurred, various other hazardous materials removal or remediation obligations under environmental laws. At December 31, 2025, Williams has accrued liabilities totaling $42 million for these matters, as discussed below. Estimates of the most likely costs of cleanup are generally based on completed assessment studies, preliminary results of studies, or Williams’ experience with other similar cleanup operations. At December 31, 2025, certain assessment studies were still in process for which the ultimate outcome may yield different estimates of most likely costs. Therefore, the actual costs incurred will depend on the final amount, type, and extent of contamination discovered at these sites, the final cleanup standards mandated by the EPA or other governmental authorities, and other factors. Continuing operations Williams’ interstate gas pipelines are involved in remediation and monitoring activities related to certain facilities and locations for polychlorinated biphenyls (PCBs), mercury, and other hazardous substances. These activities have involved the EPA and various state environmental authorities, resulting in Williams’ identification as a potentially responsible party (PRP) at various Superfund waste sites. At December 31, 2025, Williams has accrued liabilities of $11 million (see Transco and NWP below) for these costs and expects to recover approximately $3 million through rates. Williams also accrues environmental remediation costs for natural gas underground storage facilities, primarily related to soil and groundwater contamination. At December 31, 2025, Williams has accrued liabilities totaling $9 million for these costs. Former operations Williams has potential obligations in connection with assets and businesses it no longer operates. These potential obligations include remediation activities at the direction of federal and state environmental authorities and the indemnification of the purchasers of certain of these assets and businesses for environmental and other liabilities existing at the time the sale was consummated. At December 31, 2025, Williams has accrued environmental liabilities of $22 million related to these matters. Transco Transco has had studies underway for many years to test some of its facilities for the presence of toxic and hazardous substances such as PCBs and mercury to determine to what extent, if any, remediation may be necessary. Transco has also similarly evaluated past on-site disposal of hydrocarbons at a number of its facilities. Transco has worked closely with and responded to data requests from the EPA and state agencies regarding such potential contamination of certain of its sites. Transco is conducting environmental assessments and implementing a variety of remedial measures that may result in increases or decreases in the total estimated costs. Transco also has a program for monitoring certain environmental activities at its Eminence storage facility. At December 31, 2025, Transco has accrued liabilities of approximately $10 million for the expected ongoing remediation and monitoring costs. Transco has been identified as a PRP at various Superfund and state waste disposal sites. Based on present volumetric estimates and other factors, its estimated aggregate exposure for remediation of these sites is less than $1 million. The estimated remediation costs for all of these sites are included in the environmental liabilities discussed above. Liability under the Comprehensive Environmental Response, Compensation and Liability Act and applicable state law can be joint and several with other PRPs. Although volumetric allocation is a factor in assessing liability, it is not necessarily determinative; thus, the ultimate liability could be substantially greater than the amounts described above. Transco considers prudently incurred environmental assessment and remediation costs and the costs associated with compliance with environmental standards to be recoverable through rates. Historically, with limited exceptions, it has been permitted recovery of environmental costs, and it is Transco’s intent to continue seeking recovery of such costs through future rate filings. NWP Beginning in the mid-1980s, NWP evaluated many of its facilities for the presence of toxic and hazardous substances to determine to what extent, if any, remediation might be necessary. NWP identified PCB contamination in air compressor systems, soils, and related properties at certain compressor station sites. Similarly, it identified hydrocarbon impacts at these facilities due to the former use of earthen pits, lubricating oil leaks or spills, and excess pipe coating released to the environment. In addition, heavy metals have been identified at these sites due to the former use of mercury containing meters and paint and welding rods containing lead, cadmium, and arsenic. The PCBs were remediated pursuant to a Consent Decree with the EPA in the late 1980s, and NWP conducted a voluntary clean-up of the hydrocarbon and mercury impacts in the early 1990s. In 2005, the Washington Department of Ecology required NWP to re-evaluate previous clean-ups in Washington. During 2006 to 2015, 129 meter stations were evaluated, of which 82 required remediation. As of December 31, 2025, two meter stations are still being remediated. During 2006 to 2018, 14 compressor stations were evaluated, of which 11 required remediation. As of December 31, 2025, four compressor stations are still being remediated. NWP had accrued liabilities totaling approximately $1 million at December 31, 2025 for the ongoing remediation. NWP is conducting environmental assessments and implementing a variety of remedial measures that may result in increases or decreases in the total estimated costs. Environmental expenditures are expensed or capitalized depending on their future economic benefit and potential for rate recovery. NWP believes that, with respect to any expenditures required to meet applicable standards and regulations, the FERC would grant the requisite rate relief so that substantially all of such expenditures would be permitted to be recovered through rates. Washington State Climate Commitment Act In 2021, the state of Washington passed its Climate Commitment Act establishing a market-based cap-and-invest program to reduce carbon emissions. This program took effect on January 1, 2023, and sets a limit, or cap, on overall carbon emissions in the state and requires businesses like NWP to obtain allowances equal to its annual covered carbon emissions. The state’s cap will be reduced over time to meet the state’s carbon emissions reduction targets, which means fewer carbon emissions allowances will be available to purchase each year. These allowances can be purchased through quarterly auctions hosted by the state or bought and sold on a secondary market. In 2023, NWP began purchasing allowances for the carbon emissions from nine of its thirteen compressor stations within the state whose annual carbon emissions have exceeded 25,000 metric tons of carbon dioxide equivalent at least once since 2015. Additionally, NWP has program obligations as a natural gas supplier and began purchasing allowances for NWP’s delivery of natural gas to certain of its customers and certain of its facilities in the state whose annual carbon emissions are insufficient to require its direct participation in the program. NWP’s latest rate case settlement allows it to recover the costs of purchasing allowances under the program in its next rate case. At December 31, 2025 and 2024, totals of $72 million and $38 million, respectively, were included in Regulatory assets and were comprised of the cost of the purchased allowances held, the estimated difference between the allowances held and the allowances required, and the interest income component of the regulatory asset. At December 31, 2025 and December 31, 2024, $6 million and $3 million, respectively, were recorded in Other current liabilities as the estimated difference. Interest income of $4 million for the year ended December 31, 2025, and $2 million for the year ended December 31, 2024, were reflected in Other income (expense) – net. Other Divestiture Indemnifications Pursuant to various purchase and sale agreements relating to divested businesses and assets, Williams has indemnified certain purchasers against liabilities that they may incur with respect to the businesses and assets acquired. The indemnities provided to the purchasers are customary in sale transactions and are contingent upon the purchasers incurring liabilities that are not otherwise recoverable from third parties. At December 31, 2025, other than as previously disclosed, Williams is not aware of any material claims against it involving the above-described indemnities. Any claim for indemnity brought against Williams in the future may have a material adverse effect on Williams’ results of operations in the period in which the claim is made. In addition to the foregoing, various other proceedings are pending against Williams that are incidental to its operations, none of which are expected to be material to Williams’ expected future annual results of operations, liquidity, and financial position. Summary Williams, Transco, and NWP have disclosed estimated ranges of reasonably possible losses for certain matters above, as well as all significant matters for which they are unable to reasonably estimate a range of possible loss. Williams, Transco, and NWP estimate that for all other matters for which they are able to reasonably estimate a range of loss, the aggregate reasonably possible losses beyond amounts accrued are immaterial to expected future annual results of operations, liquidity, and financial position. These calculations have been made without consideration of any potential recovery from third parties. Commitments Commitments for construction and acquisition of property, plant, and equipment for Williams, Transco, and NWP are approximately $4.3 billion, $414 million, and $57 million, respectively at December 31, 2025. A significant portion of the Williams commitment relates to acquisition of long-lead time equipment for the data center power innovation projects, which are backed by reimbursement from the customer if the equipment order is cancelled. Commitments for Gas & NGL Marketing Services pipeline transportation capacity and storage capacity are approximately $974 million at December 31, 2025, a majority of which is expected to be paid over the next five years. Actual payments for Gas & NGL Marketing Services were approximately $301 million in 2025, $293 million in 2024, and $244 million in 2023 for pipeline transportation capacity and storage capacity. Williams has also entered a long-term LNG purchase obligation at market-based prices for approximately 10 percent of the volumes produced by Louisiana LNG, expected to begin in 2029. It is expected that the purchased LNG can be sold at market-based prices.

Equity-Based Compensation (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Williams Companies Incentive Plan [Member]
Equity-Based Compensation (Textuals) [Abstract]
Shares authorized for issuance	50.0
Shares reserved for future issuance	13.0
Shares available for future grants	7.0
Equity-based compensation expense	$ 93	$ 99	$ 77
Tax benefit from equity-based compensation expense	22	$ 24	$ 19
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized [Abstract]
Unrecognized equity-based compensation expense	$ 78
Unrecognized equity-based compensation expense, Weighted-average period of recognition in years	1 year 9 months 18 days
Williams Companies Incentive Plan [Member] \| Nonvested Restricted Stock Units [Member]
Rollforward of nonvested restricted stock unit activity and related information
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	5.1	6.4
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Williams Companies Incentive Plan [Member] \| Performance Shares [Member]
Rollforward of nonvested restricted stock unit activity and related information
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1.6
Williams Companies Incentive Plan [Member] \| Performance Shares [Member] \| Minimum [Member]
Rollforward of nonvested restricted stock unit activity and related information
Range of vested shares based on extent to which certain financial targets are achieved	0.00%
Williams Companies Incentive Plan [Member] \| Performance Shares [Member] \| Maximum [Member]
Rollforward of nonvested restricted stock unit activity and related information
Range of vested shares based on extent to which certain financial targets are achieved	200.00%
Williams Companies Incentive Plan [Member] \| Stock options [Member]
Rollforward of stock option activity and related information
Options Outstanding, Ending Balance	0.3
Options Exercisable at Period End	0.3
Employee Stock Purchase Plan [Member]
Equity-Based Compensation (Textuals) [Abstract]
Shares available for future grants	0.5

Revenue Recognition Contract Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	$ 1,046	$ 1,081
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	198	183
Contract with Customer, Liability, Increase (Decrease) for Contract Acquired in Business Combination	23	53
Other Significant Noncash Transaction, Value of Consideration Received	7	8
Reclassification Of Contract Liabilities To Liabilities Held For Sale	(19)	0
Contract with Customer, Liability, Revenue Recognized	(307)	(279)
Contract with Customer, Liability - End of Period	948	1,046
Transcontinental Gas Pipe Line Company, LLC [Member]
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	173	184
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	0	0
Contract with Customer, Liability, Increase (Decrease) for Contract Acquired in Business Combination	0	0
Other Significant Noncash Transaction, Value of Consideration Received	0	0
Reclassification Of Contract Liabilities To Liabilities Held For Sale	0	0
Contract with Customer, Liability, Revenue Recognized	(10)	(11)
Contract with Customer, Liability - End of Period	163	173
Northwest Pipeline LLC [Member]
Contract With Customer, Liability [Line Items]
Contract with Customer, Liability - Beginning of Period	0	2
Contract with Customer, Liability, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress	0	0
Contract with Customer, Liability, Increase (Decrease) for Contract Acquired in Business Combination	0	0
Other Significant Noncash Transaction, Value of Consideration Received	0	0
Reclassification Of Contract Liabilities To Liabilities Held For Sale	0	0
Contract with Customer, Liability, Revenue Recognized	0	(2)
Contract with Customer, Liability - End of Period	$ 0	$ 0

Provision (Benefit) for Income Taxes Deferred Tax Table (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Gross deferred income tax liabilities:
Property, plant and equipment	$ 5,116	$ 4,501
Investments	1,718	1,733
Other	237	193
Total gross deferred income tax liabilities	7,071	6,427
Gross deferred income tax assets:
Accrued liabilities	1,142	1,146
Corporate alternative minimum tax credits	203	108
Federal loss carryovers	224	325
Disallowed business interest expense carryforward	117	247
State losses and credits	171	224
Other	127	92
Total gross deferred income tax assets	1,984	2,142
Less valuation allowance	83	91
Net deferred income tax assets	1,901	2,051
Deferred income tax liabilities	$ 5,170	$ 4,376

Segment Disclosures Recon from Segment to Consolidated - Assets and Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	$ 4,518	$ 4,107	$ 4,614
Total assets	58,573	54,532	52,627
Current assets	3,244	2,661	4,513
Other Assets, Noncurrent	2,011	1,830	1,573
Payments to Acquire Productive Assets	5,424	5,598	4,313
Operating Segments [Member] \| Transmission, Power & Gulf [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	512	272	652
Total assets	26,515	23,149	19,705
Payments to Acquire Productive Assets	3,845	4,399	2,501
Operating Segments [Member] \| Northeast G & P [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	3,236	3,346	3,477
Total assets	12,533	12,918	13,319
Payments to Acquire Productive Assets	209	210	340
Operating Segments [Member] \| West [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	460	476	477
Total assets	12,398	12,144	12,188
Payments to Acquire Productive Assets	1,067	529	1,186
Operating Segments [Member] \| Gas & NGL Marketing Services
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	292	0	0
Total assets	317	46	77
Payments to Acquire Productive Assets	1	2	7
Operating Segments [Member] \| Reportable Segment, Aggregation before Other Operating Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	4,500	4,094	4,606
Total assets	51,763	48,257	45,289
Payments to Acquire Productive Assets	5,122	5,140	4,034
Corporate, Non-Segment \| Other Operating Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Equity-method investments	18	13	8
Total assets	1,555	1,784	1,252
Payments to Acquire Productive Assets	$ 302	$ 458	$ 279

Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2025

Regulated Operations [Abstract]

Schedule of Regulatory Assets

Williams


	December 31,
	2025		2024
	(Millions)
Current assets reported within Other current assets and deferred charges	$	130	$	84
Noncurrent assets reported within Regulatory assets, deferred charges, and other	568		582
Total regulatory assets	$	698	$	666


Current liabilities reported within Other current liabilities	$	117	$	85
Noncurrent liabilities reported within Regulatory liabilities, deferred income, and other	1,202		1,300
Total regulatory liabilities	$	1,319	$	1,385

Transco


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	70	$	47

ARO	51		16
Deferred cash out	—		6
ARO - Eminence	5		5
Total current regulatory assets	126		74
Long-term regulatory assets:
ARO	195		243
Grossed-up deferred taxes on equity AFUDC	28		29
ARO - Eminence	10		15
Slug catcher	6		6

Other	29		27
Total long-term regulatory assets	268		320
Total regulatory assets	$	394	$	394

Current regulatory liabilities:
Electric power cost	$	59	$	26
Deferred taxes - liability	18		31
Postretirement benefits other than pension	5		—
Pension	5		—
Deferred cash out	5		—
Other	1		1
Total current regulatory liabilities	93		58
Long-term regulatory liabilities:
Negative salvage	592		632
Deferred taxes - liability	246		252
Postretirement benefits other than pension	22		31
Pension	22		30
Sentinel meter station depreciation	7		7
Other	25		24
Total long-term regulatory liabilities	914		976
Total regulatory liabilities	$	1,007	$	1,034

NWP


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	—	$	4
Levelized depreciation	3		2
Total current regulatory assets	3		6
Long-term regulatory assets:
Levelized depreciation	5		7
Grossed-up deferred taxes on equity AFUDC	3		4
Washington State Carbon and Greenhouse Gas Tax	72		38
Total long-term regulatory assets	80		49
Total regulatory assets	$	83	$	55

Current regulatory liabilities:

Deferred taxes - liability	$	20	$	20

Fuel recovery	—		—
Total current regulatory liabilities	20		20
Long-term regulatory liabilities:
Deferred taxes - liability	146		160
Postretirement benefits other than pension	44		43
Negative salvage - net	35		30

Total long-term regulatory liabilities	225		233
Total regulatory liabilities	$	245	$	253

Schedule of Regulatory Liabilities

Williams


	December 31,
	2025		2024
	(Millions)
Current assets reported within Other current assets and deferred charges	$	130	$	84
Noncurrent assets reported within Regulatory assets, deferred charges, and other	568		582
Total regulatory assets	$	698	$	666


Current liabilities reported within Other current liabilities	$	117	$	85
Noncurrent liabilities reported within Regulatory liabilities, deferred income, and other	1,202		1,300
Total regulatory liabilities	$	1,319	$	1,385

Transco


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	70	$	47

ARO	51		16
Deferred cash out	—		6
ARO - Eminence	5		5
Total current regulatory assets	126		74
Long-term regulatory assets:
ARO	195		243
Grossed-up deferred taxes on equity AFUDC	28		29
ARO - Eminence	10		15
Slug catcher	6		6

Other	29		27
Total long-term regulatory assets	268		320
Total regulatory assets	$	394	$	394

Current regulatory liabilities:
Electric power cost	$	59	$	26
Deferred taxes - liability	18		31
Postretirement benefits other than pension	5		—
Pension	5		—
Deferred cash out	5		—
Other	1		1
Total current regulatory liabilities	93		58
Long-term regulatory liabilities:
Negative salvage	592		632
Deferred taxes - liability	246		252
Postretirement benefits other than pension	22		31
Pension	22		30
Sentinel meter station depreciation	7		7
Other	25		24
Total long-term regulatory liabilities	914		976
Total regulatory liabilities	$	1,007	$	1,034

NWP


	December 31,
	2025		2024
	(Millions)
Current regulatory assets:
Fuel recovery	$	—	$	4
Levelized depreciation	3		2
Total current regulatory assets	3		6
Long-term regulatory assets:
Levelized depreciation	5		7
Grossed-up deferred taxes on equity AFUDC	3		4
Washington State Carbon and Greenhouse Gas Tax	72		38
Total long-term regulatory assets	80		49
Total regulatory assets	$	83	$	55

Current regulatory liabilities:

Deferred taxes - liability	$	20	$	20

Fuel recovery	—		—
Total current regulatory liabilities	20		20
Long-term regulatory liabilities:
Deferred taxes - liability	146		160
Postretirement benefits other than pension	44		43
Negative salvage - net	35		30

Total long-term regulatory liabilities	225		233
Total regulatory liabilities	$	245	$	253

Fair Value Measurements, Guarantees, and Concentration of Credit Risk

12 Months Ended

Dec. 31, 2025

Fair Value Disclosures [Abstract]

Fair Value Measurements, Guarantees, and Concentration of Credit Risk [Text Block]

Note 16 – Fair Value Measurements, Guarantees, and Concentration of Credit Risk


					Fair Value Measurements Using
	Carrying Amount		Fair Value		Quoted Prices In Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(Millions)
Assets (liabilities) at December 31, 2025:
Measured on a recurring basis:
ARO Trust - Transco	$	356	$	356	$	356	$	—	$	—
Commodity derivative assets (1)	336		722		431		158		133
Commodity derivative liabilities (1)	(340)		(915)		(497)		(270)		(148)


Additional disclosures:


Guarantees	(35)		(28)		—		(12)		(16)
Debt by issuer, including current portion:
Williams	(21,649)		(21,556)		—		(21,556)		—
Transco	(5,888)		(5,941)		—		(5,941)		—
NWP	(748)		(747)		—		(747)		—
MountainWest	(376)		(385)		—		(385)		—
Total debt	(28,661)		(28,629)		—		(28,629)		—

Assets (liabilities) at December 31, 2024:
Measured on a recurring basis:
ARO Trust - Transco	$	297	$	297	$	297	$	—	$	—
Commodity derivative assets (1)	344		726		427		188		111
Commodity derivative liabilities (1)	(400)		(1,070)		(532)		(475)		(63)

Additional disclosures:

Guarantees	(36)		(28)		—		(12)		(16)
Debt by issuer, including current portion:
Williams	(20,167)		(19,517)		—		(19,517)		—
Transco	(5,235)		(5,276)		—		(5,276)		—
NWP	(582)		(573)		—		(573)		—
MountainWest	(372)		(364)		—		(364)		—
Gulf Coast Storage deferred consideration (Note 3)	(100)		(100)		—		(100)		—
Total debt	(26,456)		(25,830)		—		(25,830)		—

(1)The carrying amount is presented net of counterparty offsetting arrangements and collateral (see Note 17 – Commodity Derivatives).

Fair Value Methods

The following methods and assumptions are used in estimating the fair value of financial instruments:

Assets and Liabilities Measured at Fair Value on a Recurring Basis

ARO Trust

Transco is entitled to collect rates in the amounts necessary to fund its future AROs and deposits a portion of the collected rates into an external ARO Trust. The ARO Trust invests in a moderate risk portfolio of actively traded mutual funds that are measured at fair value on a recurring basis based on quoted prices in an active market and is reported in Regulatory assets, deferred charges, and other in Williams’ Consolidated Balance Sheet and in Deferred charges and other in the Transco Balance Sheet. The Money market fund held in the ARO Trust is considered an investment. Both realized and unrealized gains and losses are ultimately recorded to the ARO regulatory asset.

Effective March 1, 2026, the annual funding obligation is approximately $51 million. See Note 18 – Contingencies and Commitments for additional information.

Investments within the ARO Trust were as follows:


	December 31, 2025				December 31, 2024
	Amortized Cost Basis		Fair Value		Amortized Cost Basis		Fair Value
	(Millions)
Money market fund	$	34	$	34	$	27	$	27
U.S. equity funds	53		169		53		146
International equity fund	32		51		32		40
Municipal bond fund	104		102		88		84
Total	$	223	$	356	$	200	$	297

Commodity derivatives

Williams’ commodity derivatives include exchange-traded contracts and OTC contracts, which consist of physical forwards, futures, and swaps that are measured at fair value on a recurring basis. Williams also has other derivatives related to asset management agreements and other contracts that require physical delivery. Derivatives classified as Level 1 are valued using New York Mercantile Exchange (NYMEX) futures prices. Derivatives classified as Level 2 are valued using basis transactions that represent the cost to transport natural gas from a NYMEX delivery point to the contract delivery point. These transactions are based on quotes obtained either through electronic trading platforms or directly from brokers. Derivatives classified as Level 3 are valued using a combination of observable and unobservable inputs. See Note 17 – Commodity Derivatives for additional information.

The following table presents a reconciliation of changes in fair value of the net commodity derivatives classified as Level 3 in the fair value hierarchy.




	Year Ended December 31,
	2025		2024
	(Millions)
Balance at beginning of period	$	48	$	53
Gains (losses) included in Williams’ Consolidated Statement of Income	50		(5)
Purchases, issuances, and settlements	(31)		(1)
Transfers into Level 3	(78)		1
Transfers out of Level 3	(4)		—
Balance at end of period	$	(15)	$	48

The derivatives classified within Level 3, including those transferred in during 2025, primarily reflect long-term energy commodity contracts valued based on pricing inputs that include internally-developed estimates for prices beyond observable periods, which are considered significant unobservable inputs to the valuation.

Additional Fair Value Disclosures

Guarantees

Guarantees primarily consist of a guarantee Williams has provided in the event of nonpayment by a previously owned communications subsidiary, Williams Communications Group, Inc., (WilTel), on a lease performance obligation that extends through 2042. Guarantees also include an indemnification related to a disposed operation.

To estimate the fair value of the WilTel guarantee, an estimated default rate is applied to the sum of the future contractual lease payments using an income approach. The estimated default rate is determined by obtaining the average cumulative issuer-weighted default rate based on the credit rating of WilTel’s current owner and the term of the underlying obligation. The default rate is published by Moody’s Investors Service. The carrying value of the WilTel guarantee is reported in Other current liabilities. The maximum potential undiscounted liquidity exposure is approximately $21 million at December 31, 2025. The exposure declines systematically through the remaining term of WilTel’s obligation.

The fair value of the guarantee associated with the indemnification related to a disposed operation was estimated using an income approach that considered probability-weighted scenarios of potential levels of future performance. The terms of the indemnification do not limit the maximum potential future payments associated with the guarantee. The carrying value of this guarantee is reported in Regulatory liabilities, deferred income, and other.

Williams is required by its revolving credit agreement to indemnify lenders for certain taxes required to be withheld from payments due to the lenders and for certain tax payments made by the lenders. The maximum potential amount of future payments under these indemnifications is based on the related borrowings and such future payments cannot currently be determined. These indemnifications generally continue indefinitely unless limited by the underlying tax regulations and have no carrying value. Williams has never been called upon to perform under these indemnifications and there is no current expectation of a future claim.

Long-term debt, including current portion

The disclosed fair value of long-term debt is determined primarily by a market approach using broker quoted indicative period-end bond prices. The quoted prices are based on observable transactions in less active markets for the debt or similar instruments. The fair values of the financing obligations associated with Transco’s Dalton, Leidy South, and Atlantic Sunrise projects, as well as the deferred consideration obligation associated with the Gulf Coast

Storage Acquisition (see Note 3 – Acquisitions and Divestitures), all included within long-term debt including current portion, were determined using an income approach (see Note 13 – Debt and Banking Arrangements).

Nonrecurring fair value measurements

In December 2025, Williams’ management approved a plan to sell certain gas gathering assets in the Mid-Continent region. These operations were designated as held for sale at December 31, 2025. As a result, the fair value of the disposal group was measured using the expected sales price under a contract with a third party which resulted in an impairment of $176 million, which included Intangible assets – net, within the West segment and is included in Impairment or write-off of certain assets within Operating income (loss). These inputs resulted in a fair value measurement of $48 million within Level 2 of the fair value hierarchy. The estimated fair value of the Property, plant, and equipment – net and Intangible assets – net were determined using a market approach, which incorporated indications of interest from third parties.

In September 2025, Williams’ management decided to abandon certain compression assets in the DJ Basin resulting in a $25 million write-off of Property, plant, and equipment – net within the West segment. This write-off represents a Level 3 measurement within the fair value hierarchy, reflecting significant unobservable inputs, and is included in Impairment or write-off of certain assets within Operating income (loss).

Concentration of Credit Risk

Accounts receivable

The following table summarizes Williams’ concentration of receivables, net of allowances:


	December 31,
	2025		2024
	(Millions)
Natural gas, NGLs, and related products and services	$	575	$	594
Regulated interstate natural gas transportation and storage	404		339
Marketing of natural gas and NGLs	535		516
Upstream activities	18		45
Accounts receivable related to revenues from contracts with customers	1,532		1,494
Receivables from derivatives	444		294
Other accounts receivable	108		75
Trade accounts and other receivables - net	$	2,084	$	1,863

Williams’ customers include producers, distribution companies, industrial users, gas marketers, and pipelines primarily located in the continental United States. As a general policy, collateral is not required for receivables with the exception of the marketing receivables discussed below. Customers’ financial condition and credit worthiness are evaluated regularly; and, based upon this evaluation, Williams may obtain collateral to support receivables.

Williams uses established credit policies to determine and monitor the creditworthiness of gas marketing and trading counterparties, including requirements to post collateral or other credit security, as well as the quality of pledged collateral. Collateral or credit security is most often in the form of cash or letters of credit from an investment-grade financial institution, but may also include U.S. government securities. Williams also utilizes netting agreements whenever possible to mitigate exposure to gas marketing and trading counterparty credit risk. When more than one derivative transaction with the same counterparty is outstanding and a legally enforceable netting agreement exists with that counterparty, the “net” mark-to-market exposure represents a reasonable measure of the credit risk with that counterparty.

Transco and NWP receivables from contracts with customers are included within Receivables - Trade and Receivables - Affiliates. Receivables that are not related to contracts with customers are included within the balance of Receivables - Advances to affiliate and Receivables - Other.

Revenues

Customers representing 10 percent or more of Transco’s and NWP’s revenues include:


	Year Ended December 31,
	2025		2024		2023
	(Millions)
Transco:
Dominion Energy, Inc (1)	$	216	$	217	$	287

NWP:
Puget Sound Energy, Inc.	$	139	$	136	$	126
Northwest Natural Gas Company	49		47		47
Cascade Natural Gas Corporation	48		46		47

_______________

(1) The 2025 and 2024 amounts are less than 10 percent of Transco’s revenue.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2E
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2E

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 940
-SubTopic 820
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Variable Interest Entities (Tables)

12 Months Ended

Dec. 31, 2025

Variable Interest Entity Disclosures [Abstract]

Schedule of Variable Interest Entities [Table Text Block]

The following table presents amounts included in the Consolidated Balance Sheet that are only for the use or obligation of the consolidated VIEs:


	December 31,

	2025		2024 (1)
	(Millions)
Assets (liabilities):
Cash and cash equivalents	$	53	$	15
Trade accounts and other receivables	155		178
Inventories	6		5
Other current assets and deferred charges	5		7
Property, plant, and equipment – net	4,412		4,896
Intangible assets – net	1,831		1,940
Regulatory assets, deferred charges, and other	23		27
Accounts payable	(56)		(57)
Other current liabilities	(19)		(29)

Regulatory liabilities, deferred income, and other	(78)		(263)

__________

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References + Details

Revenue Recognition Contract Liabilities Performance Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	$ 948	$ 1,046	$ 1,081
Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	163	173	184
Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0	$ 0	$ 2
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	169
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	10
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	145
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	10
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	120
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	11
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	91
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	11
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	68
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	10
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	355
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	111
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Contract with Customer, Liability	$ 0
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Performance Obligations Related To Contract Liabilities [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period

Revenue Recognition Remaining Performance Obligations (Details) $ in Millions	Dec. 31, 2025 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 32,171
Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	21,933
Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	3,761
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,589
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,990
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	399
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	4,265
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,772
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	386
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	3,865
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,576
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	367
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,970
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	1,846
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	348
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	2,703
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	1,759
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	342
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	13,779
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	9,990
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Amount	$ 1,919
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Transcontinental Gas Pipe Line Company, LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Remaining Performance Obligations [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2031-01-01 \| Northwest Pipeline LLC [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period

Leases (Details) - USD ($) $ in Millions	12 Months Ended
Leases (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Lease, Cost [Abstract]
Operating lease cost	$ 39	$ 39	$ 38
Variable lease cost	33	31	31
Sublease income	0	0	(1)
Total lease cost	72	70	68
Cash paid for operating lease liabilities	40	37	37
Assets and Liabilities, Lessee [Abstract]
Right-of-use-assets	$ 170	$ 154
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Operating lease noncurrent liability	$ 151	$ 142
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities and Deferred Revenue, Noncurrent	Other Liabilities and Deferred Revenue, Noncurrent
Weighted-average remaining lease term – operating leases (years)	10 years	11 years
Weighted-average discount rate – operating leases	4.99%	4.90%
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2026	$ 40
2027	36
2028	28
2029	25
2030	21
Thereafter	87
Total future lease payments	237
Amount representing interest	$ 54
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities
Total obligations under operating leases	$ 183
Williams Companies Inc [Member]
Assets and Liabilities, Lessee [Abstract]
Operating lease current liability	$ 32	$ 26
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Transcontinental Gas Pipe Line Company, LLC [Member]
Lease, Cost [Abstract]
Operating lease cost	$ 11	$ 9	9
Variable lease cost	7	7	7
Total lease cost	18	16	16
Cash paid for operating lease liabilities	12	9	10
Assets and Liabilities, Lessee [Abstract]
Right-of-use-assets	$ 64	$ 48
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Operating lease current liability	$ 9	$ 6
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Operating lease noncurrent liability	$ 63	$ 51
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Weighted-average remaining lease term – operating leases (years)	12 years	13 years
Weighted-average discount rate – operating leases	4.84%	4.77%
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2026	$ 12
2027	13
2028	12
2029	13
2030	12
Thereafter	36
Total future lease payments	98
Amount representing interest	$ 26
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities
Total obligations under operating leases	$ 72
Northwest Pipeline LLC [Member]
Lease, Cost [Abstract]
Operating lease cost	1	$ 3	1
Variable lease cost	0	1	1
Total lease cost	1	4	2
Cash paid for operating lease liabilities	1	2	$ 1
Assets and Liabilities, Lessee [Abstract]
Right-of-use-assets	$ 4	$ 5
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Operating lease current liability	$ 0	$ 1
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities
Operating lease noncurrent liability	$ 4	$ 5
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Weighted-average remaining lease term – operating leases (years)	18 years	19 years
Weighted-average discount rate – operating leases	4.66%	4.90%
Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]
2026	$ 0
2027	1
2028	0
2029	1
2030	0
Thereafter	4
Total future lease payments	6
Amount representing interest	$ 2
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities
Total obligations under operating leases	$ 4