Item 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of ONEOK, Inc.

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of ONEOK, Inc. and its subsidiaries (the "Company") as of December 31, 2025 and 2024, and the related consolidated statements of income, of comprehensive income, of equity and of cash flows for each of the three years in the period ended December 31, 2025, including the related notes (collectively referred to as the "consolidated financial statements"). We also have audited the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control - Integrated Framework (2013) issued by the COSO.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

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Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Critical Audit Matters

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Revenue Recognition – Liquids Commodity Sales

As described in Note A to the consolidated financial statements, the Company records revenue from liquids commodity sales when the commodity is delivered to the customer as this represents the point in time when control of the product is transferred to the customer. Revenue is recorded based on the contracted selling price, which is generally index-based and settled daily or monthly. The Company recognized liquids commodity sales of $25,566 million for the year ended December 31, 2025.

The principal consideration for our determination that performing procedures relating to revenue recognition for liquids commodity sales is a critical audit matter is a high degree of auditor effort in performing procedures related to the Company’s revenue recognition.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the revenue recognition process for liquids commodity sales. These procedures also included, among others, (i) testing revenue recognized for a sample of liquids commodity sales revenue transactions by obtaining and inspecting source documents, such as contracts, settlement statements, invoices, and payments receipts and (ii) confirming a sample of outstanding customer invoices balances as of December 31, 2025, and for confirmations not returned, obtaining and inspecting source documents, such as contracts, settlement statements, invoices, and subsequent payment receipts.

s/ PricewaterhouseCoopers LLP

Tulsa, Oklahoma

February 24, 2026

We have served as the Company’s auditor since 2007.

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ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF INCOME
									Years Ended December 31,
															2025						2024						2023
												(Millions of dollars, except per share amounts)
Revenues
Commodity sales															$	28,878					$	17,780					$	15,614
Services and other															4,751						3,918						2,063
Total revenues (Note Q)															33,629						21,698						17,677
Cost of sales and fuel (exclusive of items shown separately below)															23,373						13,311						11,929
Operations and maintenance															2,585						2,162						1,319
Depreciation and amortization															1,514						1,134						769
General taxes															378						334						216
Transaction costs (Note B)															81						73						158
Other operating income, net (Notes A and B)															(43)						(305)						(786)
Operating income															5,741						4,989						4,072
Equity in net earnings from investments (Note N)															386						439						202
Other income, net															146						53						89
Interest expense (net of capitalized interest of $68, $62 and $43, respectively)															(1,783)						(1,371)						(866)
Income before income taxes															4,490						4,110						3,497
Income taxes (Note M)															(1,028)						(998)						(838)
Net income															3,462						3,112						2,659
Less: Net income attributable to noncontrolling interests															69						77						—
Net income attributable to ONEOK															3,393						3,035						2,659
Less: Preferred stock dividends															—						1						1
Net income available to common shareholders															$	3,393					$	3,034					$	2,658
Basic EPS (Note J)															$	5.43					$	5.19					$	5.49
Diluted EPS (Note J)															$	5.42					$	5.17					$	5.48
Average shares (millions)
Basic															624.8						584.6						484.3
Diluted															625.9						586.5						485.4

See accompanying Notes to Consolidated Financial Statements.

ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
						Years Ended December 31,
						2025						2024						2023
						(Millions of dollars)
Net income						$	3,462					$	3,112					$	2,659
Other comprehensive income (loss), net of tax
Change in fair value of derivatives, net of tax of $(19), $16 and $(46), respectively						59						(53)						155
Derivative amounts reclassified to net income, net of tax of $1, $5 and $21, respectively						(2)						(16)						(66)
Changes in benefit plan obligations and other, net of tax of $(3), $(2) and $3, respectively						12						6						(14)
Total other comprehensive income (loss), net of tax						69						(63)						75
Comprehensive income						3,531						3,049						2,734
Less: Comprehensive income attributable to noncontrolling interests						69						77						—
Comprehensive income attributable to ONEOK						$	3,462					$	2,972					$	2,734

See accompanying Notes to Consolidated Financial Statements.

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ONEOK, Inc. and Subsidiaries
CONSOLIDATED BALANCE SHEETS
						December 31,
						2025						2024
Assets						(Millions of dollars)
Current assets
Cash and cash equivalents						$	78					$	733
Accounts receivable, net						3,010						2,326
Inventories						948						748
Other current assets						452						431
Total current assets						4,488						4,238
Property, plant and equipment
Property, plant and equipment						55,489						52,274
Accumulated depreciation and amortization						7,628						6,339
Net property, plant and equipment (Note E)						47,861						45,935
Other assets
Investments in unconsolidated affiliates (Note N)						2,889						2,316
Goodwill (Note F)						8,058						8,091
Intangible assets, net (Note F)						2,901						3,039
Other assets						444						450
Total other assets						14,292						13,896
Total assets						$	66,641					$	64,069
Liabilities and equity
Current liabilities
Current maturities of long-term debt (Note G)						$	1,241					$	1,059
Short-term borrowings (Note G)						820						—
Accounts payable						2,838						2,187
Commodity imbalances						217						260
Accrued interest						499						511
Other current liabilities						750						702
Total current liabilities						6,365						4,719
Long-term debt, excluding current maturities (Note G)						30,755						31,018
Deferred credits and other liabilities
Deferred income taxes (Note M)						6,349						5,451
Other deferred credits						603						748
Total deferred credits and other liabilities						6,952						6,199
Commitments and contingencies (Note O)
Equity (Note H)
Preferred stock, $0.01 par value: authorized 100,000,000 shares; issued and outstanding 0 shares at December 31, 2025; issued and outstanding 20,000 shares at December 31, 2024						—						—
Common stock, $0.01 par value: authorized 1,200,000,000 shares; issued 655,909,018 shares and outstanding 629,707,691 shares at December 31, 2025; issued 609,713,834 shares and outstanding 583,110,633 shares at December 31, 2024						7						6
Paid-in capital						20,961						16,354
Accumulated other comprehensive loss						(27)						(96)
Retained earnings						2,373						1,579
Treasury stock, at cost: 26,201,327 shares at December 31, 2025, and 26,603,201 shares at December 31, 2024						(829)						(807)
Total ONEOK shareholders' equity						22,485						17,036
Noncontrolling interests in consolidated subsidiaries						84						5,097
Total equity						22,569						22,133
Total liabilities and equity						$	66,641					$	64,069

See accompanying Notes to Consolidated Financial Statements.

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ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF CASH FLOWS
						Years Ended December 31,
						2025						2024						2023
						(Millions of dollars)
Operating activities
Net income						$	3,462					$	3,112					$	2,659
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization						1,514						1,134						769
Equity in net earnings from investments (Note N)						(386)						(439)						(202)
Distributions received from unconsolidated affiliates						397						390						202
Deferred income taxes (Note M)						957						889						829
Gain on sale of business (Note B)						—						(227)						—
Medford settlement gain (Note A)						—						—						(779)
Medford settlement proceeds (Note A)						—						—						502
Other, net						35						72						83
Changes in assets and liabilities:
Accounts receivable						(683)						49						107
Inventories, net of commodity imbalances						(263)						17						118
Accounts payable						671						114						(62)
Other assets and liabilities, net						(105)						(223)						195
Cash provided by operating activities						5,599						4,888						4,421
Investing activities
Capital expenditures (less allowance for equity funds used during construction)						(3,152)						(2,021)						(1,595)
Cash paid for acquisitions, net of cash acquired						(25)						(5,829)						(5,015)
Proceeds from the sale of business (Note B)						—						1,200						—
Purchases of and contributions to unconsolidated affiliates (Note N)						(622)						(111)						(207)
Medford settlement proceeds (Note A)						—						—						328
Other, net						48						149						85
Cash used in investing activities						(3,751)						(6,612)						(6,404)
Financing activities
Dividends paid						(2,583)						(2,313)						(1,839)
Short-term borrowings, net						820						—						—
Issuance of long-term debt, net of discounts (Note G)						2,989						7,094						5,298
Debt financing costs						(32)						(67)						(71)
Repurchase of common stock (Note H)						(75)						(159)						—
Delaware Basin JV Acquisition (Note B)						(550)						—						—
Extinguishment of long-term debt (Note G)						(2,979)						(2,003)						(1,300)
Repurchase of EnLink's Series C Preferred Units						—						(365)						—
Other, net						(93)						(68)						13
Cash provided by (used in) financing activities						(2,503)						2,119						2,101
Change in cash and cash equivalents						(655)						395						118
Cash and cash equivalents at beginning of period						733						338						220
Cash and cash equivalents at end of period						$	78					$	733					$	338
Supplemental cash flow information:
Cash paid for interest, net of amounts capitalized						$	1,732					$	1,297					$	653

See accompanying Notes to Consolidated Financial Statements.

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ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY
			ONEOK Shareholders' Equity
			Preferred Stock			Common Stock			Paid-in Capital			AOCL*			Retained Earnings			Treasury Stock			Noncontrolling Interests			Total Equity
			(Millions of dollars)
January 1, 2023			$	—		$	5		$	7,253		$	(108)		$	50		$	(706)		$	—		$	6,494
Net income			—			—			—			—			2,659			—			—			2,659
Other comprehensive income			—			—			—			75			—			—			—			75
Preferred stock dividends - $55.00 per share			—			—			—			—			(1)			—			—			(1)
Magellan Acquisition consideration (Note B)			—			1			9,061			—			—			—			—			9,062
Common stock issued			—			—			9			—			—			29			—			38
Common stock dividends - $3.82 per share (Note H)			—			—			—			—			(1,839)			—			—			(1,839)
Other, net			—			—			(3)			—			(1)			—			—			(4)
December 31, 2023			—			6			16,320			(33)			868			(677)			—			16,484
Net income			—			—			—			—			3,035			—			77			3,112
Other comprehensive loss			—			—			—			(63)			—			—			—			(63)
Preferred stock dividends - $55.00 per share			—			—			—			—			(1)			—			—			(1)
Common stock issued			—			—			25			—			—			42			—			67
Common stock dividends - $3.96 per share (Note H)			—			—			—			—			(2,318)			—			—			(2,318)
Repurchase of common stock (Note H)			—			—			—			—			—			(172)			—			(172)
EnLink Controlling Interest Acquisition (Note B)			—			—			—			—			—			—			5,076			5,076
Distributions to noncontrolling interests																					(66)			(66)
Contributions from noncontrolling interests			—			—			—			—			—			—			3			3
Other, net			—			—			9			—			(5)			—			7			11
December 31, 2024			—			6			16,354			(96)			1,579			(807)			5,097			22,133
Net income			—			—			—			—			3,393			—			69			3,462
Other comprehensive income			—			—			—			69			—			—			—			69
Preferred stock dividends - $13.75 per share			—			—			—			—			—			—			—			—
Common stock issued			—			—			(9)			—			—			40			—			31
Common stock dividends - $4.12 per share (Note H)			—			—			—			—			(2,596)			—			—			(2,596)
Repurchase of common stock (Note H)			—			—			—			—			—			(62)			—			(62)
EnLink Acquisition (Note B)			—			1			4,377			—			—			—			(4,378)			—
Delaware Basin JV Acquisition (Note B)			—			—			185			—			—			—			(678)			(493)
Distributions to noncontrolling interests			—			—			—			—			—			—			(47)			(47)
Contributions from noncontrolling interests			—			—			—			—			—			—			19			19
Other, net			—			—			54			—			(3)			—			2			53
December 31, 2025			$	—		$	7		$	20,961		$	(27)		$	2,373		$	(829)		$	84		$	22,569

*Accumulated other comprehensive loss

See accompanying Notes to Consolidated Financial Statements.

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ONEOK, INC. AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

A. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Organization and Nature of Operations - We are a corporation incorporated under the laws of the state of Oklahoma.

Our Natural Gas Gathering and Processing segment provides midstream services to producers in the Rocky Mountain region, the Mid-Continent region and the Permian Basin. Raw natural gas is typically gathered at the wellhead, compressed and transported through pipelines to our processing facilities. Most raw natural gas produced at the wellhead also contains a mixture of NGL components, including ethane, propane, iso-butane, normal butane and natural gasoline. Gathered wellhead natural gas is directed to our processing plants to remove NGLs, resulting in residue natural gas (primarily methane). Residue natural gas is then recompressed and delivered to natural gas pipelines, storage facilities and end users. The NGLs separated from the raw natural gas are delivered through NGL pipelines to fractionation facilities for further processing.

In our Natural Gas Liquids segment, NGLs are extracted at our own and third-party natural gas processing plants and are gathered by our NGL gathering pipelines. Gathered NGLs are directed to our downstream fractionators to be separated into Purity NGLs. Purity NGLs are stored or distributed to our customers, such as petrochemical companies, propane distributors, diluent users, ethanol producers, refineries and exporters. We provide midstream services to producers of NGLs in the Rocky Mountain region, Mid-Continent region, Permian Basin and Gulf Coast region and deliver those products to the market. Our primary markets include the Mid-Continent in Conway, Kansas, the Gulf Coast in Mont Belvieu, Texas, Louisiana and the upper Midwest. The majority of the pipeline-connected natural gas processing plants in the Williston Basin, Oklahoma, Kansas and the Texas Panhandle as well as a large number in the Permian Basin, Barnett Shale, East Texas and Louisiana regions are connected to our NGL gathering systems.

In our Natural Gas Pipelines segment, we receive residue natural gas from third parties and our own natural gas processing plants and interconnecting pipelines. Residue natural gas is transported or stored for end users, such as large industrial customers, natural gas and electric utilities serving commercial and residential consumers and can ultimately reach international markets through liquified natural gas exports (Louisiana Gulf Coast) and cross border pipelines. Our assets are connected to key supply areas and demand centers, including export markets in Mexico via Roadrunner and supply areas in Canada and the United States via our interstate and intrastate natural gas pipelines, Northern Border and Matterhorn, which enables us to provide essential natural gas transportation and storage services. Growing demand from data centers and continued demand from local distribution companies, electric-generation facilities and large industrial companies support capital projects and low-cost expansions that position us well to provide additional services to our customers when needed.

Our Refined Products and Crude segment is principally engaged in the transportation, storage and distribution of Refined Products and crude oil. We are also engaged in the gathering of crude oil*.* Our crude oil assets are strategically located to gather, transport and store crude oil and are connected to refineries, export facilities and multiple trading and demand centers. Throughout our distribution system, terminals play a key role in facilitating product movements and marketing by providing storage, distribution, blending and other ancillary services. Products transported on our Refined Products pipeline system include gasoline, distillates, aviation fuel and certain NGLs. Shipments originate on our Refined Products pipeline system from direct connections to refineries or through interconnections with other pipelines or terminals for transportation and ultimate distribution to retail fueling stations, convenience stores, travel centers, railroads, airports and other end users.

Basis of Presentation - Our accompanying Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the SEC. These statements have been prepared in accordance with GAAP.

Consolidation - Our Consolidated Financial Statements include our accounts and the accounts of our subsidiaries over which we have control or are the primary beneficiary. Third-party ownership interests in our controlled subsidiaries are presented as noncontrolling interests. All intercompany balances and transactions have been eliminated in consolidation.

We account for investments where we control the investment using the consolidation method of accounting. Under this method, we consolidate all assets and liabilities of an investment on our Consolidated Balance Sheets and record noncontrolling interests for the portion of the investment we do not own. We include all of the investment’s results of operations on our Consolidated Statements of Income and record income attributable to noncontrolling interests for the portion of the investment that we do not own. As of December 31, 2025, noncontrolling interests in our Consolidated Balance Sheets related to Ascension and MBTC Pipeline. As a result of the Delaware Basin JV Acquisition and the EnLink Acquisition, these entities are now wholly owned subsidiaries and are no longer recorded as noncontrolling interests in our Consolidated Balance Sheets as of December 31, 2025. As of December 31, 2024, noncontrolling interests in our Consolidated Balance Sheets were

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composed of the approximately 57% of outstanding EnLink Units we did not own, Series B Preferred Units and the partially owned consolidated subsidiaries of EnLink.

See Note H for disclosures of our noncontrolling interests.

Investments in unconsolidated affiliates are accounted for using the equity method if we have the ability to exercise significant influence over operating and financial policies of our investee. Under this method, an investment is carried at its acquisition cost and adjusted each period for contributions made, distributions received and our share of the investee’s comprehensive income. The difference between the carrying value of an investment and our share of the investment’s underlying equity in net assets is referred to as a basis difference. Basis differences related to depreciable or amortizable assets are amortized through equity in net earnings from investments. The premium or excess cost over underlying fair value of net assets is referred to as equity-method goodwill. The portion of the basis difference that is attributable to our equity-method goodwill is not amortized. Impairment of equity investments is recorded when the impairments are other than temporary. These amounts are recorded as investments in unconsolidated affiliates on our accompanying Consolidated Balance Sheets.

See Note N for disclosures of our unconsolidated affiliates.

Distributions paid to us from our unconsolidated affiliates are classified as operating activities on our Consolidated Statements of Cash Flows until the cumulative distributions exceed our proportionate share of income from the unconsolidated affiliate since the date of our initial investment. Cumulative distributions paid to us from the unconsolidated affiliate that exceed our cumulative proportionate share of income from the unconsolidated affiliate in each period represents a return of investment and is classified as an investing activity on our Consolidated Statements of Cash Flows.

Variable Interest Entities (VIEs) - We evaluate all legal entities in which we hold an ownership interest to determine if the entity is a VIE. Variable interests are ownership interests in an entity that change with changes in the fair value of the VIE’s assets. When we conclude that we hold an interest in a VIE, we must determine if we are the entity’s primary beneficiary. A primary beneficiary is deemed to have the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance. We consolidate any VIE when we determine that we are the primary beneficiary.

Significant judgment is exercised in determining that a legal entity is a VIE and in evaluating our interest in a VIE. We use primarily a qualitative analysis to determine if an entity is a VIE. We evaluate our interests in a VIE to determine whether we are the primary beneficiary. We continually monitor our interests in legal entities for changes in the design or activities of an entity and changes in our interests, including our status as the primary beneficiary to determine if the changes require us to revise our previous conclusions.

See Note I for our VIE disclosures.

Use of Estimates - The preparation of our Consolidated Financial Statements and related disclosures in accordance with GAAP requires us to make estimates and assumptions with respect to values or conditions that cannot be known with certainty that affect the reported amounts on our Consolidated Financial Statements. Items that may be estimated include, but are not limited to, the economic useful life of assets, fair value of assets, liabilities, derivative instruments and equity-method investments, obligations under employee benefit plans, allowance for credit losses, expenses for services received but for which no invoice has been received, provision for income taxes, including any deferred tax valuation allowances, the results of litigation, environmental remediation and various other recorded or disclosed amounts. In addition, a portion of our revenues and cost of sales and fuel are recorded based on current month prices and estimated volumes. The estimates are reversed in the following month when we record actual volumes.

We evaluate our estimates on an ongoing basis using historical experience, consultation with experts and other methods we consider reasonable based on the particular circumstances. Nevertheless, actual results may differ significantly from the estimates. Any effects on our financial position or results of operations from revisions to these estimates are recorded in the period when the facts that give rise to the revision become known.

Fair Value Measurements - For our fair value measurements, we utilize market prices, third-party pricing services, present value methods and standard option valuation models to determine the price we would receive from the sale of an asset or the transfer of a liability in an orderly transaction at the measurement date. We measure the fair value of a group of financial assets and liabilities consistent with how a market participant would price the net risk exposure at the measurement date.

Most of the contracts in our derivative portfolio are executed in liquid markets where price transparency exists. Our financial commodity derivatives are primarily settled through a NYMEX or Intercontinental Exchange clearing broker account with daily

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margin requirements. We validate our valuation inputs with third-party information and settlement prices from other sources, where available.

We compute the fair value of our derivative portfolio by discounting the projected future cash flows from our derivative assets and liabilities to present value using interest-rate yields to calculate present-value discount factors derived from the implied forward SOFR yield curve. The fair value of our forward-starting interest-rate swaps is determined using financial models that incorporate the implied forward SOFR yield curve for the same period as the future interest-rate swap settlements. We consider current market data in evaluating counterparties’, as well as our own, nonperformance risk, net of collateral, by using counterparty-specific bond yields. Although we use our best estimates to determine the fair value of the derivative contracts we have executed, the ultimate market prices realized could differ materially from our estimates.

Fair Value Hierarchy - At each balance sheet date, we utilize a fair value hierarchy to classify fair value amounts recognized or disclosed in our financial statements based on the observability of inputs used to estimate such fair value. The levels of the hierarchy are described below:

• Level 1 - fair value measurements are based on unadjusted quoted prices for identical securities in active markets. These balances are composed predominantly of exchange-traded derivative contracts for natural gas, Refined Products and crude oil.

• Level 2 - fair value measurements are based on significant observable pricing inputs, including quoted prices for similar assets and liabilities in active markets and inputs from third-party pricing services supported with corroborative evidence. These balances are composed of exchange cleared and over-the-counter derivatives to hedge natural gas, NGLs, Refined Products and crude oil price risk and over-the-counter interest-rate derivatives.

• Level 3 - fair value measurements are based on inputs that may include one or more unobservable inputs.

Determining the appropriate classification of our fair value measurements within the fair value hierarchy requires management’s judgment regarding the degree to which market data is observable or corroborated by observable market data. We categorize derivatives based on the lowest level input that is significant to the fair value measurement in its entirety.

See Note C for our fair value measurements disclosures.

Cash and Cash Equivalents - Cash equivalents consist of highly liquid investments, which are readily convertible into cash and have original maturities of three months or less.

Revenue Recognition - Revenues are recognized when control of the promised goods or services is transferred to our customers in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods or services. Our payment terms vary by customer and contract type, including requiring payment before products or services are delivered to certain customers. However, the term between customer prepayments, completion of our performance obligations, invoicing and receipt of payment due is generally not significant.

Performance Obligations and Revenue Sources - Revenue sources are disaggregated in Note R and are derived from commodity sales and services revenues, as described below:

Commodity Sales (all segments) - We contract to deliver residue natural gas, unfractionated NGLs and/or Purity NGLs, Refined Products, condensate and crude oil to customers at a specified delivery point. Our sales agreements may be daily or longer-term contracts for a specified volume. We consider the sale and delivery of each unit of a commodity an individual performance obligation as the customer is expected to control, accept and benefit from each unit individually. We record revenue when the commodity is delivered to the customer as this represents the point in time when control of the product is transferred to the customer. Revenue is recorded based on the contracted selling price, which is generally index-based and settled daily or monthly. Occasionally, we sell unfractionated NGLs to customers at an index-based price less third-party fractionation costs. These costs are included as a reduction to commodity sales revenue.

Services

Gathering only contracts (Natural Gas Gathering and Processing segment) - Under this type of contract, we charge fees for providing midstream services, which include gathering and treating our customers’ natural gas. Our performance obligation begins with delivery of raw natural gas to our system. This service is treated as one performance obligation that is satisfied over time. We use the output method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously.

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Fee with POP contracts with producer take-in-kind rights (Natural Gas Gathering and Processing segment) - Under this type of contract, we do not control the stream of unprocessed natural gas that we receive at the wellhead due to the producer’s take-in-kind rights. We purchase commodities that the producer does not take-in-kind and charge fees for providing midstream services, which include gathering, treating, compressing and processing our customers’ natural gas. After performing these services, we return certain commodities to the producer, sell any remaining commodities and remit a portion of the commodity sales proceeds to the producer less our contractual fees. Our performance obligation begins with delivery of raw natural gas to our system. This service is treated as one performance obligation that is satisfied over time. We use the output method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously.

Transportation, exchange and terminal service contracts (Natural Gas Liquids and Refined Products and Crude segments) - Under this type of contract, we charge fees for providing midstream services, which may include a bundled combination of one or more of the following services: gathering, transporting, terminalling, fractionation or other ancillary services. Our performance obligation begins with delivery of product to our system. These services represent a series of distinct services that are treated as one performance obligation that is satisfied over time. We use the output method based on delivery of product to our system as the measure of progress, as our services are performed simultaneously. For transportation services under a tariff on our transportation pipelines, fees are recorded when our delivery obligation is complete. We have certain contracts that require counterparties to ship a minimum volume over an agreed-upon time period, which are contracted as minimum dollar or volume commitments. Revenue pursuant to these take-or-pay contracts is initially deferred and subsequently recognized when the customers utilize their committed volumes or when the likelihood of meeting the minimum volume commitment becomes remote.

Storage contracts (Natural Gas Liquids, Refined Products and Crude and Natural Gas Pipelines segments) - We reserve a stated storage capacity and inject/withdraw/store commodities for our customers. As these services represent a stand-ready obligation provided on a daily basis over the life of the agreement, the fixed capacity reservation fees are allocated and evenly recognized in revenue over the contract term. Capacity reservation fees that vary based on a stated or implied economic index and correspond with the costs to provide our services are recognized in revenue as invoiced to our customers. We use the output method based on the passage of time to measure satisfaction of the performance obligation associated with our daily stand-ready services. Other fees are recognized in revenue as those services are provided and are dependent on the volume moved, which is at our customers’ discretion.

Firm service transportation contracts (Natural Gas Pipelines segment) - We reserve a stated transportation capacity and transport commodities for our customer. The capacity reservation and transportation services are considered a bundled service, as we integrate them into one stand-ready obligation provided on a daily basis over the life of the agreement and satisfied over time. Fixed capacity reservation fees are allocated and evenly recognized in revenue. Capacity reservation fees that vary based on a stated or implied economic index and correspond with the costs to provide our services are recognized in revenue based on a daily effective fee rate. If the capacity reservation fees vary solely as a contract feature, contract assets or liabilities are recorded for the difference between the amount recorded in revenue and the amount billed to the customer. Transportation fees are recognized in revenue as those services are provided and are dependent on the volume transported by our customer, which is at our customers’ discretion. We use the output method based on the passage of time to measure satisfaction of the performance obligation associated with our daily stand-ready services.

Interruptible transportation contracts (Natural Gas Pipelines segment) - We agree to transport natural gas on our pipelines between the customers’ specified nominated-receipt and delivery points if capacity is available after satisfying firm transportation service obligations. The transaction price is based on the transportation fees times the volumes transported. We use the output method based on delivery of product to the customer to measure satisfaction of the performance obligation. The total consideration for delivered volumes is recorded in revenue at the time of delivery, when the customer obtains control.

Many of the contract types described above contain additional fees or charges payable by customers for nonperformance (e.g., minimum volume commitments or product specifications), which are considered to be variable consideration. These fees and charges are not recorded until it is probable that a significant reversal of the associated revenue will not occur.

Receivables from Customers - Substantially all of the balances in accounts receivable on our Consolidated Balance Sheets at December 31, 2025, and December 31, 2024, are related to customer receivables.

See Note Q for our revenue disclosures.

Contract Assets and Contract Liabilities - Contract assets and contract liabilities are recorded when the amount of revenue recognized from a contract with a customer differs from the amount billed to the customer and recorded in accounts receivable. Our contract asset balances at the beginning and end of the period primarily related to our firm service transportation contracts

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with tiered rates, which are not material. Our contract liabilities at the beginning and end of the period primarily related to deferred revenue on Refined Products and crude oil transportation contracts, NGL storage contracts and contributions in aid of construction received from customers, which were not material.

Cost of Sales and Fuel - Cost of sales and fuel primarily includes (i) the cost of purchased commodities, including natural gas, NGLs, Refined Products, condensate and crude oil, (ii) fees incurred for third-party transportation, fractionation and storage of commodities, (iii) fuel and power costs incurred to operate our own facilities that gather, process, transport and store commodities, (iv) product gains and losses and (v) an offset from the contractual fees deducted from the cost of purchased commodities under the contract types below:

Fee with POP contracts with no producer take-in-kind rights (Natural Gas Gathering and Processing segment) - We purchase raw natural gas and charge contractual fees for providing midstream services, which include gathering, treating, compressing and processing the producer’s natural gas. After performing these services, we sell the commodities and return a portion of the commodity sales proceeds to the producer less our contractual fees.

Purchase with fee (Natural Gas Liquids and Refined Products and Crude segments) - Under this type of contract, we purchase product at an index price and charge fees for providing midstream services, which may include a bundled combination of gathering, transporting and/or fractionation.

Operations and Maintenance - Operations and maintenance primarily includes (i) payroll and benefit costs, (ii) third-party costs for operations, maintenance and integrity management, regulatory compliance and environmental and safety, and (iii) other business-related service costs.

Accounts Receivable - Accounts receivable represent valid claims against nonaffiliated customers for products sold or services rendered. We present accounts receivable net of an allowance for credit losses to reflect the net amount expected to be collected. We assess the creditworthiness of our counterparties on an ongoing basis and require security, including prepayments and other forms of collateral, when appropriate. Outstanding customer receivables are reviewed regularly for possible nonpayment indicators, and allowances for credit losses are recorded based upon management’s estimate of collectability, current conditions and supportable forecasts at each balance sheet date. At December 31, 2025, our allowance for credit losses was not material.

Inventory - The values of current NGLs, natural gas, Refined Products and crude oil in storage are determined using the lower of weighted-average cost or net realizable value. Materials and supplies are valued at average cost.

Commodity Imbalances - In our Natural Gas Gathering and Processing, Natural Gas Liquids and Natural Gas Pipelines segments, commodity imbalances represent amounts payable or receivable for NGL exchange contracts and natural gas pipeline imbalances and are valued at market prices. Under the majority of our NGL exchange agreements, we physically receive volumes of unfractionated NGLs, including the risk of loss and legal title to such volumes, from the exchange counterparty. In turn, we deliver Purity NGLs back to the customer and charge gathering, transportation and fractionation fees. To the extent that the volumes we receive under such agreements differ from those we deliver, we record a net exchange receivable or payable position with the counterparties. These net exchange receivables and payables are generally settled with movements of Purity NGLs rather than with cash. Natural gas pipeline imbalances are settled in cash or in-kind, subject to the terms of the pipelines’ tariffs or by agreement.

In our Refined Products and Crude segment, commodity imbalances represent differences in product volumes in our pipeline systems and terminals, compared to the volumes of our customers’ inventories, as we do not take legal title to the majority of the products on our pipeline systems and terminals. To the extent the product volumes differ from the volumes of our customers’ book inventories, we record adjustments to our product inventories. When product shortages cause a net short inventory position in a product, a liability is recorded based on market prices. Refined Products and crude oil imbalances are generally settled in-kind through product purchases and sales.

Derivatives and Risk Management - We utilize derivatives to reduce our market-risk exposure to commodity price and interest-rate fluctuations and to achieve more predictable cash flows. We record all derivative instruments at fair value, with the exception of normal purchases and normal sales transactions that are expected to result in physical delivery. Commodity price and interest-rate volatility may have a significant impact on the fair value of derivative instruments as of a given date. The accounting for changes in the fair value of a derivative instrument depends on whether it has been designated and qualifies as part of a hedging relationship and, if so, the reason for holding it.

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The table below summarizes the various ways in which we account for our derivative instruments and the impact on our Consolidated Financial Statements:

						Recognition and Measurement
Accounting Treatment						Balance Sheet						Income Statement
Normal purchases and normal sales			-			Fair value not recorded			-			Change in fair value not recognized in earnings
Mark-to-market			-			Recorded at fair value			-			Change in fair value recognized in earnings
Cash flow hedge			-			The gain or loss on the derivative instrument is reported initially as a component of accumulated other comprehensive income (loss)			-			The gain or loss on the derivative instrument is reclassified out of accumulated other comprehensive income (loss) into earnings when the forecasted transaction affects earnings
Fair value hedge			-			Recorded at fair value			-			The gain or loss on the derivative instrument is recognized in earnings
			-			Change in fair value of the hedged item is recorded as an adjustment to book value			-			Change in fair value of the hedged item is recognized in earnings

To reduce our exposure to fluctuations in natural gas, NGLs, Refined Products, condensate and crude oil prices, we periodically enter into futures, forward purchases and sales, options or swap transactions in order to hedge anticipated purchases and sales of natural gas, NGLs, Refined Products, condensate and crude oil. Treasury locks and interest-rate swaps are used from time to time to manage interest-rate risk. Under certain conditions, we designate our derivative instruments as a hedge of exposure to changes in fair values or cash flows. We formally document all relationships between hedging instruments and hedged items, as well as risk-management objectives and strategies for undertaking various hedge transactions, and methods for assessing and testing hedge effectiveness. We specifically identify the forecasted transaction that has been designated as the hedged item in a cash flow hedge relationship. We assess hedging relationships at the inception of the hedge, and periodically thereafter, to determine whether the hedging relationship is, and is expected to remain, highly effective. We also document our normal purchases and normal sales transactions that we expect to result in physical delivery and that we elect to exempt from derivative accounting treatment.

The realized revenues and purchase costs of our derivative instruments not considered held for trading purposes and derivatives that qualify as normal purchases or normal sales that are expected to result in physical delivery are reported on a gross basis.

Cash flows from futures, forwards, options and swaps that are accounted for as hedges are included in the same category as the cash flows from the related hedged items in our Consolidated Statements of Cash Flows.

See Notes C and D for disclosures of our fair value measurements and risk-management and hedging activities, respectively.

Property, Plant and Equipment - Our properties are stated at cost, including AFUDC and capitalized interest. In some cases, the cost of regulated property retired or sold, plus removal costs, less salvage, is charged to accumulated depreciation. Gains and losses from sales or transfers of nonregulated properties or an entire operating unit or system of our regulated properties are recognized in income. Maintenance and repairs are charged directly to expense.

The interest portion of AFUDC and capitalized interest represent the cost of borrowed funds used to finance construction activities for regulated and nonregulated projects, respectively. We capitalize interest costs during the construction or upgrade of qualifying assets. These costs are recorded as a reduction to interest expense. The equity portion of AFUDC represents the capitalization of the estimated average cost of equity used during the construction of major projects and is recorded in the cost of our regulated properties and as a credit to the allowance for equity funds used during construction.

Our properties are depreciated using the straight-line method over their estimated useful lives. Generally, we estimate the useful lives of individual assets or apply depreciation rates to functional groups of property having similar economic lives. We periodically conduct depreciation studies to assess the economic lives of our assets. For our regulated assets, these depreciation studies are completed as a part of our rate proceedings or tariff filings, and the changes in economic lives, if applicable, are implemented prospectively as of the approved effective date. For our nonregulated assets, if it is determined that the estimated economic life changes, the changes are made prospectively. Changes in the estimated economic lives of our property, plant and equipment could have a material effect on our financial position or results of operations.

Property, plant and equipment on our Consolidated Balance Sheets includes construction work in process for capital projects that have not yet been placed in service and therefore are not being depreciated. Assets are transferred out of construction work in process when they are substantially complete and ready for their intended use.

See Note E for our property, plant and equipment disclosures.

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Impairment of Goodwill and Long-Lived Assets, Including Intangible Assets and Equity Method Investments - We assess our goodwill for impairment at least annually as of July 1, unless events or changes in circumstances indicate an impairment may have occurred before that time. Our qualitative goodwill impairment analysis performed as of July 1, 2025, did not result in an impairment charge nor did our analysis reflect any reporting units at risk, and subsequent to that date, no event has occurred indicating that the implied fair value of our reporting units are less than the carrying value of their net assets.

Goodwill - As part of our goodwill impairment test, we assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine whether it was more likely than not that the fair value of our reporting units are less than their carrying amount. If further testing is necessary, or a quantitative test is elected, we perform a Step 1 analysis. In a Step 1 analysis, an assessment is made by comparing the fair value of a reporting unit with its carrying amount, including goodwill. If the carrying value of a reporting unit exceeds its fair value, an impairment loss is recognized in an amount equal to that excess, limited to the total amount of goodwill allocated to that reporting unit.

To estimate the fair value of our reporting units, we use two generally accepted valuation approaches, an income approach and a market approach, using assumptions consistent with a market participant’s perspective. Under the income approach, we use anticipated cash flows over a period of years plus a terminal value and discount these amounts to their present value using appropriate discount rates. The forecasted cash flows are based on probability weighted-average possible future cash flows for a reporting unit over a period of years. Under the market approach, we apply EBITDA multiples to forecasted EBITDA. The multiples used are consistent with recent market transactions.

Long-lived assets - We assess our long-lived asset groups for impairment whenever events or changes in circumstances indicate that an asset group’s carrying amount may not be recoverable. An impairment is indicated if the carrying amount of a long-lived asset group exceeds the sum of the undiscounted future cash flows expected to result from the use and eventual disposition of the asset group. If an impairment is indicated, we record an impairment loss equal to the difference between the carrying value and the fair value of the long-lived asset group.

Investments in unconsolidated affiliates - The impairment test for equity-method investments considers whether the fair value of the equity investment as a whole, not the underlying net assets, has declined and whether that decline is other than temporary. Therefore, we periodically evaluate the amount at which we carry our equity-method investments to determine whether current events or circumstances warrant adjustments to our carrying values.

See Notes E, F and N for our disclosures related to long-lived assets, goodwill and intangible assets and investments in unconsolidated affiliates, respectively.

Leases - We lease certain buildings, warehouses, office space, compression, land and equipment, including pipeline equipment, pipeline capacity, rail cars and information technology equipment. Our office space lease arrangements typically include variable lease cost related to utility expenses, which are determined based on our pro-rata share of building expenses each month and are expensed as incurred. Our lease payments are generally straight-line and the exercise of lease renewal options, which vary in term, is at our sole discretion. We include renewal periods in a lease term if we are reasonably certain to exercise available renewal options. Our lease agreements do not include any residual value guarantees or material restrictive covenants. We apply the short-term policy election, which allows us to exclude from recognition leases with an initial term of 12 months or less. Our weighted-average discount rates represent the rate implicit in the lease or our incremental borrowing rate for a term equal to the remaining term of the lease. Our finance lease assets and liabilities are not material.

Our lessor arrangements primarily include capacity, storage and service contracts and are not material. We have made an accounting policy election for both our lessee and lessor arrangements to combine lease and non-lease components. This election is applied to all of our lease arrangements as our non-lease components do not result in significant timing differences in the recognition of rental expenses or income.

Regulation - Depending on the specific service provided, our natural gas transmission pipelines, NGL, Refined Products and crude oil pipelines and certain natural gas storage facilities are subject to rate regulation and/or accounting requirements by one or more of the FERC, Oklahoma Corporation Commission, Kansas Corporation Commission, Louisiana Public Service Commission, Railroad Commission of Texas, Wyoming Public Service Commission and Colorado Public Utilities Commission. Accordingly, portions of our Natural Gas Liquids and Natural Gas Pipelines segments follow the accounting and reporting guidance for regulated operations as defined pursuant to Financial Accounting Standards Board’s (FASB) Accounting Standards Codification 980, Regulated Operations. During the rate-making process for certain of our assets, regulatory authorities set the framework for what we can charge customers for our services and establish the manner that our costs are accounted for, including allowing us to defer recognition of certain costs and permitting recovery of the amounts through rates

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over time as opposed to expensing such costs as incurred. Certain examples of types of regulatory guidance include costs for fuel and losses, acquisition costs, contributions in aid of construction, charges for depreciation, and gains or losses on disposition of assets. This allows us to stabilize rates over time rather than passing such costs on to the customer for immediate recovery. Actions by regulatory authorities could have an effect on the amounts we may charge our customers. Any difference in the amount recoverable and the amount deferred is recorded as income or expense at the time of the regulatory action. A write-off of regulatory assets and costs not recovered may be required if all or a portion of the regulated operations have rates that are no longer (i) established by independent, third-party regulators and (ii) set at levels that will recover our costs when considering the demand and competition for our services.

Retirement and Other Postretirement Employee Benefits - We maintain three defined benefit pension plans, including the ONEOK Retirement Plan, covering certain legacy ONEOK employees, and the Magellan Pension Plan and the Magellan Pension Plan for USW Employees, each covering certain legacy Magellan employees. We sponsor health and welfare plans that provide postretirement medical and life insurance benefits to certain legacy ONEOK employees hired prior to 2017 and certain legacy Magellan employees who retire after a specified age with at least five years of service and satisfy certain other conditions. The expense and liability related to these plans is calculated using statistical and other factors that attempt to anticipate future events. These factors include assumptions about the discount rate, expected return on plan assets, rate of future compensation increases, interest credit rating, mortality and employment length. In determining the projected benefit obligations and costs, assumptions can change from period to period and may result in changes in the costs and liabilities we recognize.

See Note L for our retirement and other postretirement employee benefits disclosures.

Income Taxes - Deferred income taxes are provided for the difference between the financial statement and income tax basis of assets and liabilities and carryforward items based on income tax laws and rates existing at the time the temporary differences are expected to reverse. Generally, the effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date of the rate change.

We utilize a more-likely-than-not recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position that is taken or expected to be taken in a tax return. We reflect penalties and interest as part of income tax expense as they become applicable for tax provisions that do not meet the more-likely-than-not recognition threshold and measurement attribute. For all periods presented, we had no uncertain tax positions that required the establishment of a material reserve.

We utilize the “with-and-without” approach for intra-period tax allocation for purposes of allocating total tax expense (or benefit) for the year among the various financial statement components.

We file numerous consolidated and separate income tax returns with federal tax authorities of the United States along with the tax authorities of several states. EnLink Midstream Operating, LP and EnLink Partners are both in the process of federal review by the Internal Revenue Service for the calendar years ended December 31, 2019, and December 31, 2020, and statute waivers are in place for these years. At this time, we believe the audits will close without a material impact. No other ONEOK entity is under any United States federal audits or statute waivers at this time.

See Note M for our income tax disclosures.

Asset Retirement Obligations - Asset retirement obligations represent legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development and/or normal use of the asset. Certain of our gathering and processing and pipeline facilities are subject to agreements or regulations that give rise to our asset retirement obligations for removal or other disposition costs associated with retiring the assets in place upon the discontinued use of the assets. We recognize the fair value of a liability for an asset retirement obligation in the period when it is incurred if a reasonable estimate of the fair value can be made. We are not able to estimate reasonably the fair value of the asset retirement obligations for portions of our assets, primarily certain pipeline assets, because the settlement dates are indeterminable given our expected continued use of the assets with proper maintenance. We expect our pipeline assets, for which we are unable to estimate reasonably the fair value of the asset retirement obligation, will continue in operation as long as supply and demand for natural gas, NGLs, Refined Products and crude oil exist. Based on the widespread use of these products in the medical, transportation, synthetics and agriculture industries, as well as for residential and industrial customers and electric generation, we expect supply and demand to exist for the foreseeable future.

For assets in which we are able to make an estimate, the fair value of the liability is added to the carrying amount of the associated asset, and this additional carrying amount is depreciated over the life of the asset. The liability is accreted at the end

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of each period through charges to operating expense. If the obligation is settled for an amount other than the carrying amount of the liability, we will recognize a gain or loss on settlement. The depreciation and accretion expense are immaterial to our Consolidated Financial Statements.

Contingencies - Our accounting for contingencies covers a variety of business activities, including contingencies for legal and environmental exposures. We accrue these contingencies when our assessments indicate that it is probable that a liability has been incurred or an asset will not be recovered, and an amount can be estimated reasonably. We expense legal fees as incurred and base our legal liability estimates on currently available facts and our estimates of the ultimate outcome or resolution. Accruals for estimated losses from environmental remediation obligations generally are recognized no later than completion of a remediation feasibility study. Our expenditures for environmental evaluation, mitigation, remediation and compliance to date have not been material in relation to our financial position or results of operations, and our expenditures related to environmental matters did not have a material effect on earnings or cash flows during 2025, 2024 and 2023. Actual results may differ from our estimates resulting in an impact, positive or negative, on earnings.

See Note O for additional discussion of contingencies.

Share-Based Payments - We expense the fair value of share-based payments net of estimated forfeitures. We estimate forfeiture rates based on historical forfeitures under our share-based payment plans.

See Note K for our share-based payments disclosures.

Earnings per Common Share - Basic EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period, vested restricted and performance units that have been deferred and share awards deferred under the compensation plan for non-employee directors. Diluted EPS is calculated based on the daily weighted-average number of shares of common stock outstanding during the period plus potentially dilutive components. The dilutive components are calculated based on the dilutive effect for each quarter. For fiscal-year periods, the dilutive components for each quarter are averaged to arrive at the fiscal year-to-date dilutive component.

See Note J for our EPS disclosures.

Segment Reporting - In accordance with the “Segment Reporting” Topic 280, our chief operating decision-maker has been identified as the chief executive officer, who reviews the financial performance of each of our four segments to make decisions about allocating resources and assessing our financial performance as a whole, on a regular basis. Adjusted EBITDA by segment is the single measure of profit and loss utilized in this evaluation by our chief executive officer and is provided through monthly and quarterly review packages. Forecasted and actual adjusted EBITDA is used in the evaluation and approval of capital projects. We believe this financial measure is useful because it and similar measures are used by many companies in our industry as a measurement of financial performance and are commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. Adjusted EBITDA for each segment is defined as net income adjusted for interest expense, depreciation and amortization, noncash impairment charges, income taxes, noncash compensation expense and certain other noncash items. Adjusted EBITDA from our unconsolidated affiliates is calculated consistently with the definition above and excludes items such as interest expense, depreciation and amortization, income taxes and other noncash items. Although the amounts related to our unconsolidated affiliates are included in the calculation of adjusted EBITDA, such inclusion should not be understood to imply that we have control over the operations and resulting revenues, expenses or cash flows of such unconsolidated affiliates. This calculation may not be comparable with similarly titled measures of other companies.

See Note R for our segments disclosures.

Medford Insurance Proceeds - In 2022, a fire occurred at our 210 MBbl/d Medford, Oklahoma, NGL fractionation facility. In the first quarter of 2023, we reached an agreement with our insurers to settle all claims for physical damage and business interruption related to the Medford incident. Under the terms of the settlement agreement, we agreed to resolve the claims for total insurance payments of $930 million, $100 million of which was received in 2022. The remaining $830 million was received in the first quarter of 2023. The proceeds serve as settlement for property damage, business interruption claims to the date of the settlement and as payment in lieu of future business interruption insurance claims. We applied the $830 million received to our outstanding insurance receivable at December 31, 2022, of $51 million, and recorded an operational gain for the remaining $779 million in other operating income, net, within the Consolidated Statement of Income for the year ended December 31, 2023. We classified proceeds received within the Consolidated Statement of Cash Flows based on our assessment of the nature of the loss (property and business interruption) included in the settlement.

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Recently Issued Accounting Standards Update - Changes to GAAP are established by the FASB in the form of Accounting Standards Update (ASUs) to the FASB Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not discussed herein were assessed and determined to be either not applicable or clarifications of ASUs previously issued. Except as discussed below, there have been no new accounting pronouncements that have become effective or have been issued that are of significance or potential significance to us.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires public entities, on an annual basis, to provide disclosure of specific disaggregated information about the reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024, with early adoption permitted. We adopted this standard in 2025 and updated our income tax disclosures retrospectively. See Note M.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40), which requires public entities to provide disaggregated information for certain types of costs and expenses included in each income statement caption, such as inventory purchases, employee compensation, depreciation, intangible asset amortization and depletion. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027, with early adoption permitted. We are currently evaluating the impact of this standard on our disclosures.

In November 2025, the FASB issued ASU 2025-09, Derivatives and Hedging – Hedge Accounting Improvements (Topic 815), which is intended to enhance or clarify Topic 815 to better align hedge accounting with the economics of an entity’s risk management activities, allow hedging of groups of forecasted transactions and expand the types of hedge transactions that can be aggregated. Additionally, the guidance allows entities to designate a variable price component of a nonfinancial forecasted transaction, facilitate hedge accounting on variable-rate debt and provides clarification related to reference rate reform. ASU 2025-09 is effective for fiscal years beginning after December 15, 2026, with early adoption permitted. We elected to adopt this guidance beginning in the first quarter 2026. The adoption of this standard did not materially impact us.

B. ACQUISITIONS AND DIVESTITURES

BridgeTex Additional Interest Acquisition - On July 22, 2025, we completed the BridgeTex Additional Interest Acquisition. Pursuant to the purchase agreement, we paid approximately $270 million in cash, which we funded with short-term borrowings. Following the completion of the transaction, we now have a 60% ownership interest in BridgeTex. Our investment in BridgeTex will continue to be accounted for using the equity method as we continue to have the ability to exercise significant influence over the operating and financial policies of BridgeTex, although we do not have the ability to exercise control.

Delaware Basin JV Acquisition - On May 28, 2025, we completed the Delaware Basin JV Acquisition for $941 million. Pursuant to the purchase agreement, we paid $550 million in cash, including post-closing adjustments, which we funded with short-term borrowings and issued approximately 4.9 million shares of ONEOK common stock to the seller with a fair value of $391 million as of the closing date. Following the completion of the transaction, it is now a wholly owned subsidiary.

As we controlled the Delaware Basin JV at December 31, 2024, prior to the Delaware Basin JV Acquisition, the change in our ownership interest was accounted for as an equity transaction, and no gain or loss was recognized in our Consolidated Statement of Income from the acquisition. The Delaware Basin JV Acquisition was a taxable exchange. The transaction resulted in a decrease to the carrying value of noncontrolling interests in consolidated subsidiaries at the acquisition date of $678 million and an increase to paid-in capital of $185 million, including deferred tax assets.

EnLink Acquisition - On January 31, 2025, we completed the EnLink Acquisition. Pursuant to the EnLink Merger Agreement, each publicly held common unit of EnLink was exchanged for a fixed ratio of 0.1412 shares of ONEOK common stock, including EnLink Units that were exchanged for all previously outstanding Series B Preferred Units immediately prior to closing. We issued 41 million shares of common stock with a fair value of $4.0 billion. As a result of the completion of the EnLink Acquisition, common units of EnLink are no longer publicly traded, and EnLink is now a wholly owned subsidiary.

As we controlled EnLink at December 31, 2024, prior to the EnLink Acquisition, the change in our ownership interest was accounted for as an equity transaction. The carrying value of the noncontrolling interests in consolidated subsidiaries at the acquisition date was $4.4 billion. The difference between the equity consideration and the carrying value of the noncontrolling interests in consolidated subsidiaries at the acquisition date was recognized as an adjustment to paid-in capital.

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Supplemental Cash Flow Information - Our noncash balance sheet activity related to the EnLink Acquisition is as follows (in millions):

Common stock						$	1
Paid-in capital						$	4,377
Noncontrolling interests in consolidated subsidiaries						$	(4,378)

EnLink Controlling Interest Acquisition - On October 15, 2024, we completed the EnLink Controlling Interest Acquisition, acquiring GIP’s interest in EnLink consisting of approximately 43% of the outstanding EnLink Units for $14.90 in cash per unit and 100% of the outstanding limited liability company interests in the managing member of EnLink for $300 million, for total cash consideration of $3.3 billion. Through our 100% ownership of the managing member of EnLink, we obtained control of EnLink. We used a portion of the proceeds from our September 2024 underwritten public offering of $7.0 billion senior unsecured notes to fund this acquisition. For additional information on our long-term debt, see Note G.

This acquisition meaningfully increased our scale and integrated value chain within the growing Permian Basin while expanding and extending our asset bases in the Mid-Continent, North Texas and Louisiana regions.

The EnLink Controlling Interest Acquisition was accounted for using the acquisition method of accounting for business combinations pursuant to Accounting Standards Codification 805, “Business Combinations,” which requires, among other things, assets acquired and liabilities assumed to be recorded at their fair value on the acquisition date. Determining the fair value of acquired assets and liabilities assumed required management to make estimates, assumptions and judgments, and in some cases, management also utilized third-party specialists to assist and advise on those estimates.

The following tables set forth the acquisition consideration and final purchase price allocation of assets acquired and liabilities assumed:

			October 15, 2024
			(Millions of dollars and units, except per unit data)
EnLink Units outstanding
43% of EnLink Units outstanding			200.3
Cash consideration per EnLink unit			$14.90
Cash consideration for EnLink Units			$	2,985
100% of the outstanding liability company interests in the managing member of EnLink			300
Total cash consideration			$	3,285

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			October 15, 2024
Assets acquired:			(Millions of dollars)
Cash and cash equivalents			$	446
Accounts receivables, net			551
Inventories			87
Other current assets			38
Property, plant and equipment			11,447
Investments in unconsolidated affiliates			342
Intangible assets			1,051
Other assets			129
Total assets acquired			14,091
Liabilities assumed:
Current maturities of long-term debt			758
Accounts payable			465
Other current liabilities (a)			532
Long-term debt, excluding current maturities			4,577
Deferred income taxes			1,988
Other deferred credits and liabilities			90
Total liabilities assumed			8,410
Noncontrolling interests			5,076
Total identifiable net assets			605
Goodwill			2,680
Total purchase price			$	3,285

(a) - Included obligation to repay Series C Preferred Units. See Note H.

In 2025, there were no material changes to the preliminary purchase price allocation as disclosed in our 2024 Annual Report.

Property, plant and equipment:

Property, plant and equipment consisted primarily of pipeline and rights of way, pipeline-related equipment and processing plant and fractionators and will be depreciated on a straight-line basis over the estimated useful lives of the assets.

Intangible assets:

Net identifiable intangible assets related to customer relationships that will be amortized over the period of expected benefit.

Long-term debt, excluding current maturities:

We utilized publicly traded prices to estimate the fair value. The debt comprised senior unsecured obligations with varying maturities and interest rates as outlined in Note G. Recognizing the debt at its acquisition date fair value resulted in a discount from the notional value. The discount was immaterial and will be amortized into interest expense over the remaining life of the debt.

Deferred income taxes:

The EnLink Controlling Interest Acquisition resulted in a difference between the carrying value of the underlying assets acquired and the carryover tax basis of assets, which resulted in a deferred tax liability recorded as part of the purchase price allocation.

Goodwill:

We established deferred income tax liabilities resulting from carryover tax basis, which increased goodwill. The remainder of the goodwill balance primarily represented commercial synergies. Goodwill will not be deductible for tax purposes. For additional information on goodwill, see Note F.

Noncontrolling interest:

Represented the approximately 57% of EnLink Units not acquired in the EnLink Controlling Interest Acquisition, valued at the acquisition date closing price of EnLink, the Series B Preferred Units and partially owned consolidated subsidiaries.

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Results of operations:

The results of operations attributable to the EnLink Controlling Interest Acquisition have been included in our Consolidated Financial Statements since the date of acquisition. Revenue and income before income taxes attributable to the net assets acquired for the period October 15, 2024, through December 31, 2024, were $1.5 billion and $173 million, respectively.

Medallion Acquisition - On October 31, 2024, we completed the Medallion Acquisition with GIP, acquiring all of the equity interests in Medallion for total cash consideration of $2.6 billion, inclusive of the purchase of additional interests in a Medallion joint venture owned by a separate third party. We used a portion of the proceeds from our September 2024 underwritten public offering of $7.0 billion senior unsecured notes to fund this acquisition. For additional information on our long-term debt, see Note G.

This acquisition expanded our midstream services for crude oil and condensate in West Texas, specifically the Midland Basin. The assets of Medallion included crude oil gathering and transportation pipelines and crude oil storage facilities. Medallion’s assets and operations are reported in our Refined Products and Crude segment.

The Medallion Acquisition was accounted for using the acquisition method of accounting for business combinations pursuant to Accounting Standards Codification 805, “Business Combinations,” which requires, among other things, assets acquired and liabilities assumed to be recorded at their fair value on the acquisition date. Determining the fair value of acquired assets and liabilities assumed required management to make estimates, assumptions and judgments, and in some cases, management also utilized third-party specialists to assist and advise on those estimates.

The following table sets forth the final purchase price allocation of assets acquired and liabilities assumed:

			October 31, 2024
Assets acquired:			(Millions of dollars)
Cash and cash equivalents			$	36
Accounts receivables, net			114
Other current assets			22
Property, plant and equipment			1,596
Intangible assets			730
Other assets			2
Total assets acquired			2,500
Liabilities assumed:
Accounts payable			103
Other current liabilities			3
Other deferred credits and liabilities			40
Total liabilities assumed			146
Total identifiable net assets			2,354
Goodwill			263
Total purchase price			$	2,617

In 2025, there were no material changes to the preliminary purchase price allocation as disclosed in our 2024 Annual Report.

Property, plant and equipment:

Property, plant and equipment consisted primarily of pipeline and pump station equipment and will be depreciated on a straight-line basis over the estimated useful lives of the assets.

Intangible assets:

Net identifiable intangible assets related to customer relationships that will be amortized over the period of expected benefit.

Goodwill:

Goodwill represented commercial synergies and is expected to be fully deductible for tax purposes. For additional information on goodwill, see Note F.

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Results of operations:

The results of operations attributable to the Medallion Acquisition have been included in our Consolidated Financial Statements since the date of acquisition. Revenue and income before income taxes attributable to the net assets acquired for the period November 1, 2024, through December 31, 2024, were $256 million and $43 million, respectively.

Gulf Coast NGL Pipelines Acquisition - On June 17, 2024, we completed the acquisition of a system of NGL pipelines from Easton Energy, a Houston-based midstream company, for approximately $280 million. This acquisition in our Natural Gas Liquids segment included approximately 450 miles of liquids products pipelines located in the strategic Gulf Coast market centers for NGLs, Refined Products and crude oil.

Interstate Natural Gas Pipeline Divestiture - On December 31, 2024, we sold three of our wholly owned interstate natural gas pipeline systems to DT Midstream, Inc. for total cash consideration of $1.2 billion and recognized a gain of $227 million in other operating income, net, within the Consolidated Statement of Income for the year ended December 31, 2024. This transaction aligned and enhanced our capital allocation priorities within our integrated value chain. These pipeline systems were previously reported in our Natural Gas Pipelines segment.

Magellan Acquisition - On September 25, 2023, we completed the Magellan Acquisition. This acquisition strategically diversified our complementary asset base and allows for significant expected synergies as a combined entity. Each common unit of Magellan was exchanged for a fixed ratio of 0.667 shares of ONEOK common stock and $25.00 of cash, for a total consideration of $14.1 billion. A total of approximately 135 million shares of common stock were issued, with a fair value of approximately $9.0 billion as of the closing date of the Magellan Acquisition. We funded the cash portion of this acquisition with an underwritten public offering of $5.25 billion senior unsecured notes. For additional information on our long-term debt, please see Note G.

The Magellan Acquisition was accounted for using the acquisition method of accounting for business combinations pursuant to Accounting Standards Codification 805, “Business Combinations,” which requires, among other things, assets acquired and liabilities assumed to be recorded at their fair value on the acquisition date. Determining the fair value of acquired assets and liabilities assumed required management to make estimates, assumptions and judgments, and in some cases, management also utilized third-party specialists to assist and advise on those estimates.

The following tables set forth the acquisition consideration and final purchase price allocation of assets acquired and liabilities assumed:

			September 25, 2023
			(Millions of dollars and shares/units, except per share/unit data)
Magellan public common units outstanding			202.1
Cash consideration per Magellan unit			$25.00
Cash consideration			$	5,052
Magellan public common units outstanding			202.1
ONEOK exchange ratio per Magellan unit			0.667
Shares of ONEOK common stock issued			134.8
ONEOK common stock closing price on September 25, 2023			$66.54
Fair value of common stock issued			$	8,969
Fair value of Magellan replacement equity awards			93
Equity consideration			$	9,062
Total consideration			$	14,114

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			September 25, 2023
Assets acquired:			(Millions of dollars)
Cash and cash equivalents			$	37
Accounts receivables, net			333
Inventories			352
Other current assets			140
Property, plant and equipment			11,644
Investments in unconsolidated affiliates			922
Intangible assets			1,124
Other assets			121
Total assets acquired			14,673
Liabilities assumed:
Accounts payable			213
Other current liabilities			721
Long-term debt, excluding current maturities			4,013
Other deferred credits and liabilities			201
Total liabilities assumed			5,148
Total identifiable net assets			9,525
Goodwill			4,589
Total purchase price			$	14,114

Intangible assets:

The preliminary value of net identifiable intangible assets related to customer relationships that will be amortized over the period of expected benefit.

Goodwill:

Goodwill primarily represented expected tax benefits from future depreciation and amortization of acquired assets and commercial synergies, and is expected to be fully deductible for tax purposes. For additional information on goodwill, see Note F.

Transaction Costs - The following table sets forth the impact of acquisition-related transaction costs in our Consolidated Statements of Income as of the periods indicated:

															Years Ended
															December 31,
																		2025 (a)						2024 (b)						2023 (c)
															(Millions of dollars)
Transaction costs																		$	81					$	73					$	158
Interest expense																		—						23						21
Total																		$	81					$	96					$	179

(a) - Primarily nonrecurring costs including $65 million related primarily to advisory fees and severance and $16 million of noncash compensation expense related to the settlement of share-based awards for certain EnLink employees associated with the EnLink Acquisition.

(b) - Primarily nonrecurring costs related to advisory fees and bridge commitment fees associated with the EnLink Controlling Interest Acquisition and Medallion Acquisition.

(c) - Primarily nonrecurring costs related to advisory fees, severance and settlement of share-based awards for certain Magellan employees and integration costs, as well as bridge facility commitment fees associated with the Magellan Acquisition.

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Pro Forma Financial Information (unaudited)

The following table sets forth the unaudited supplemental pro forma financial information for the years ended December 31, 2024 and 2023, as if we had completed the Magellan Acquisition on January 1, 2022, and the EnLink Controlling Interest Acquisition and the Medallion Acquisition on January 1, 2023:

																								Year Ended December 31, 2024
																														Pro Forma EnLink Controlling Interest Acquisition						Pro Forma Medallion Acquisition						Pro Forma Combined
																																				As reported
																		(Millions of dollars)
Revenues																																				$	21,698					$	4,579					$	1,078					$	27,355
Net income																																				$	3,112					$	288					$	81					$	3,481

																								Year Ended December 31, 2023
																														Pro Forma EnLink Controlling Interest Acquisition						Pro Forma Medallion Acquisition						Pro Forma Magellan Acquisition			Pro Forma Combined
																																				As reported
																		(Millions of dollars)
Revenues																																				$	17,677					$	6,239					$	947					$	2,322		$	27,185
Net income																																				$	2,659					$	383					$	(16)					$	232		$	3,258

The summarized unaudited pro forma information reflects the following adjustments:

• Reflects depreciation and amortization based on the final fair values of property, plant and equipment, and intangible assets;

• Reflects nonrecurring transaction costs incurred presented above that were reclassified and included in pro forma net income as if they had been incurred as of the earliest period presented for each respective acquisition;

• Reflects interest expense related to the underwritten public offerings of senior unsecured notes used to fund the cash consideration and other costs related to the acquisitions;

• Reflects the amortization of excess fair value of Magellan and EnLink share-based awards;

• Reflects the income tax effect of the pro forma adjustments;

• Reflects the elimination of historical activity between ONEOK, Magellan, EnLink and Medallion.

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C. FAIR VALUE MEASUREMENTS

Recurring Fair Value Measurements - The following tables set forth our recurring fair value measurements as of the dates indicated:

			December 31, 2025
			Level 1						Level 2						Level 3						Total - Gross						Netting (a)						Total - Net
			(Millions of dollars)
Derivative assets
Commodity contracts			$	60					$	69					$	—					$	129					$	(67)					$	62
Total derivative assets			$	60					$	69					$	—					$	129					$	(67)					$	62
Derivative liabilities
Commodity contracts			$	(21)					$	(46)					$	—					$	(67)					$	67					$	—
Total derivative liabilities			$	(21)					$	(46)					$	—					$	(67)					$	67					$	—

(a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2025, we held no cash and posted cash of $4 million with a counterparty, which is included in other current assets in our Consolidated Balance Sheets.

			December 31, 2024
			Level 1						Level 2						Level 3						Total - Gross						Netting (a)						Total - Net
			(Millions of dollars)
Derivative assets
Commodity contracts			$	41					$	34					$	—					$	75					$	(72)					$	3
Total derivative assets			$	41					$	34					$	—					$	75					$	(72)					$	3
Derivative liabilities
Commodity contracts			$	(40)					$	(46)					$	—					$	(86)					$	81					$	(5)
Total derivative liabilities			$	(40)					$	(46)					$	—					$	(86)					$	81					$	(5)

(a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis. We net derivative assets and liabilities when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us. At December 31, 2024, we held no cash and posted cash of $45 million with a counterparty, including $10 million of cash collateral that is offsetting derivative net liability positions under master-netting arrangements in the table above. The remaining $35 million of cash collateral in excess of derivative liability positions is included in other current assets in our Consolidated Balance Sheets.

Other Financial Instruments - The approximate fair value of cash and cash equivalents, accounts receivable, accounts payable and short-term borrowings is equal to book value due to the short-term nature of these items. Our cash and cash equivalents are composed of bank and money market accounts and are classified as Level 1. Our short-term borrowings are classified as Level 2 since the estimated fair value of the short-term borrowings can be determined using information available in the commercial paper market. We have investments associated with our supplemental executive retirement plan and nonqualified deferred compensation plan that are carried at fair value and primarily are composed of mutual funds, municipal bonds and other fixed income securities classified as Level 1 and Level 2.

The book value of our consolidated long-term debt, including current maturities, was $32.0 billion and $32.1 billion at December 31, 2025 and 2024, respectively. At December 31, 2025 and 2024, the estimated fair value of our consolidated long-term debt, including current maturities, was $32.7 billion and $31.9 billion, respectively. For comparability to the book value of our consolidated long-term debt, the unamortized debt discounts and issuance costs at December 31, 2025 and 2024, totaled $1.2 billion and $1.1 billion, respectively, which resulted in the estimated fair value, net of unamortized debt discounts and issuance costs, of $31.5 billion and $30.8 billion, respectively. The estimated fair value of the aggregate senior notes outstanding was determined using quoted market prices for similar issues with similar terms and maturities. The estimated fair value of our consolidated long-term debt is classified as Level 2.

D. RISK-MANAGEMENT AND HEDGING ACTIVITIES USING DERIVATIVES

Risk-management Activities - We are sensitive to changes in the prices of natural gas, NGLs, Refined Products and crude oil, principally as a result of contractual terms under which these commodities are processed, purchased and sold. We are also

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subject to the risk of interest-rate fluctuation in the normal course of business. We use physical-forward purchases and sales and financial derivatives to secure a certain price for a portion of our natural gas, NGLs, Refined Products, condensate and crude oil purchases and sales; to reduce our exposure to commodity price and interest-rate fluctuations; and to achieve more predictable cash flows. Additionally, we may use physical-forward purchases and financial derivatives to reduce commodity price risk associated with power and natural gas used to operate our facilities. We follow established policies and procedures to assess risk and approve, monitor and report our risk-management activities. We have not used these instruments for trading purposes.

Commodity price risk - Commodity price risk refers to the risk of loss in cash flows and future earnings arising from adverse changes in the price of natural gas, NGLs, Refined Products and crude oil. We may use the following commodity derivative instruments to reduce the near-term commodity price risk associated with a portion of our forecasted purchases and sales of these commodities:

• Futures contracts - Standardized contracts to purchase or sell natural gas and crude oil for future delivery or settlement under the provisions of exchange regulations;

• Forward contracts - Nonstandardized commitments between two parties to purchase or sell natural gas, NGLs, Refined Products, condensate and crude oil for future physical delivery. These contracts are typically nontransferable and can only be canceled with the consent of both parties;

• Swaps - Exchange of one or more payments based on the value of one or more commodities. These instruments transfer the financial risk associated with a future change in value between the counterparties of the transaction, without also conveying ownership interest in the asset or liability;

• Options - Contractual agreements that give the holder the right, but not the obligation, to buy or sell a fixed quantity of a commodity at a fixed price within a specified period of time. Options may either be standardized and exchange-traded or customized and nonexchange-traded; and

• Collars - Combination of a purchased put option and a sold call option, which places a floor and ceiling price for commodity sales being hedged.

We may also use other instruments to mitigate commodity price risk.

In our Natural Gas Gathering and Processing segment, we are exposed to commodity price risk as a result of retaining a portion of the commodity sales proceeds associated with our fee with POP contracts. Under certain fee with POP contracts, our fees and POP percentage may increase or decrease if production volumes, delivery pressures or commodity prices change relative to specified thresholds. We also are exposed to basis risk between the various production and market locations where we buy and sell commodities. As part of our hedging strategy, we use the previously described commodity derivative financial instruments and physical-forward contracts to reduce the impact of price fluctuations related to natural gas, NGLs and condensate.

In our Natural Gas Liquids segment, we are primarily exposed to commodity price risk resulting from the relative values of the various Purity NGLs to each other, the value of NGLs in storage and the relative value of NGLs to natural gas. We are also exposed to location price differential risk as a result of the relative value of NGL purchases at one location and sales at another location, primarily related to our optimization and marketing business. As part of our hedging strategy, we utilize physical-forward contracts and commodity derivative financial instruments to reduce the impact of price fluctuations related to NGLs.

In our Natural Gas Pipelines segment, we are primarily exposed to commodity price risk on our intrastate pipelines because they consume natural gas in operations and retain natural gas from our customers for operations or as part of our fee for compression services provided. When the amount consumed in operations differs from the amount provided by our customers, our pipelines must buy or sell natural gas, or store or use natural gas inventory, which can expose this segment to commodity price risk depending on the regulatory treatment for this activity. To the extent that commodity price risk in our Natural Gas Pipelines segment is not mitigated by fuel cost-recovery mechanisms, we may use physical-forward sales or purchases to reduce the impact of natural gas price fluctuations. We are also exposed to location price differential risk as a result of the relative value of natural gas purchases at one location and sales at another location, primarily related to our optimization and marketing business. As part of our hedging strategy, we utilize physical-forward contracts and commodity derivative financial instruments to reduce the impact of price fluctuations related to natural gas.

In our Refined Products and Crude segment, we are primarily exposed to commodity price risk from our liquids blending and marketing activities, as well as product retained during the operations of our pipelines and terminals. As part of our hedging strategy, we use the previously described commodity derivative financial instruments and physical-forward contracts to reduce the impact of price fluctuations related to NGLs, Refined Products and crude oil.

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Interest-rate risk - We may manage interest-rate risk through the use of fixed-rate debt, floating-rate debt, Treasury locks and interest-rate swaps. Treasury locks are agreements to pay the difference between the benchmark Treasury rate and the rate that is designated in the terms of the agreement. In the third quarter and second quarter of 2025, we entered into $300 million notional quantity and $700 million notional quantity, respectively, of Treasury locks to hedge the variability of interest payments on a portion of our forecasted debt issuances. In the third quarter of 2025, we settled all of the outstanding $1.0 billion notional quantity of Treasury locks in connection with our underwritten public offering of $3.0 billion senior unsecured notes in August 2025. All of our Treasury locks were designated as cash flow hedges.

At December 31, 2025, and December 31, 2024, we had no outstanding interest-rate derivative instruments.

Fair Values of Derivative Instruments - See Note A for a discussion of the inputs associated with our fair value measurements. The following table sets forth the fair values of our derivative instruments presented on a gross basis as of the dates indicated:

						December 31, 2025												December 31, 2024
			Location in our Consolidated Balance Sheets			Assets						(Liabilities)						Assets						(Liabilities)
						(Millions of dollars)
Derivatives designated as hedging instruments
Commodity contracts (a)(b)			Other current assets			$	112					$	(50)					$	39					$	(47)
Total derivatives designated as hedging instruments						112						(50)						39						(47)
Derivatives not designated as hedging instruments
Commodity contracts (a)(b)			Other current assets/liabilities			17						(17)						36						(33)
			Other deferred credits			—						—						—						(6)
Total derivatives not designated as hedging instruments						17						(17)						36						(39)
Total derivatives						$	129					$	(67)					$	75					$	(86)

(a) - Derivative assets and liabilities are presented in our Consolidated Balance Sheets on a net basis when a legally enforceable master-netting arrangement exists between the counterparty to a derivative contract and us.

(b) - At December 31, 2024, our derivative net liability positions under master-netting arrangements for financial commodity contracts were offset by cash collateral of $10 million.

Notional Quantities for Derivative Instruments - The following table sets forth the notional quantities for our derivative instruments, consisting of futures and swaps, held as of the dates indicated:

						December 31, 2025						December 31, 2024
						Net Purchased/Payor (Sold/Receiver)
Derivatives designated as hedging instruments:
Cash flow hedges
Fixed price
- Natural gas (Bcf)						(19.4)						(12.2)
- NGLs, Refined Products and crude oil (MMBbl)						(22.1)						(12.2)
Basis
- Natural gas (Bcf)						(17.9)						(11.2)
- NGLs, Refined Products and crude oil (MMBbl)						(0.6)						—
Derivatives not designated as hedging instruments:
Fixed price
- Natural gas (Bcf)						(4.1)						(8.0)
- NGLs, Refined Products and crude oil (MMBbl)						0.1						(2.7)
Basis
- Natural gas (Bcf)						(0.2)						(3.7)
- NGLs, Refined Products and crude oil (MMBbl)						—						(0.2)
Swing Swaps
- Natural gas (Bcf)						(0.6)						(0.2)

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Cash Flow Hedges - At December 31, 2025 and 2024, the accumulated other comprehensive income (loss) relating to risk-management assets and liabilities, net of taxes, was $19 million and $(38) million, respectively. Corresponding unrealized gains (losses) related to risk-management assets and liabilities at December 31, 2025 and 2024, are not material.

The following table sets forth the unrealized change in fair value of cash flow hedges in other comprehensive income (loss) for the periods indicated:

						Years Ended December 31,
			2025						2024						2023
						(Millions of dollars)
Commodity contracts						$	83					$	(50)					$	147
Interest-rate contracts						(5)						(19)						54
Total unrealized change in fair value of cash flow hedges in other comprehensive income (loss)						$	78					$	(69)					$	201

The following table sets forth the effect of cash flow hedges on net income for the periods indicated:

Derivatives in Cash Flow Hedging Relationships						Location of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income
						Years Ended December 31,
						2025						2024						2023
												(Millions of dollars)
Commodity contracts						Commodity sales revenues						$	53					$	60					$	201
						Cost of sales and fuel						(34)						(19)						(93)
Interest-rate contracts						Interest expense						(16)						(20)						(21)
Total change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income on derivatives												$	3					$	21					$	87

Credit Risk - We monitor the creditworthiness of our counterparties and compliance with policies and limits established by our Risk Oversight and Strategy Committee. We maintain credit policies with regard to our counterparties that we believe minimize credit risk. These policies include an evaluation of potential counterparties’ financial condition (including credit ratings, bond yields and credit default swap rates), collateral requirements under certain circumstances and the use of standardized master-netting agreements that allow us to net the positive and negative exposures associated with a single counterparty. We use internally developed credit ratings for counterparties that do not have a credit rating.

Our financial commodity derivatives are primarily settled through a NYMEX or Intercontinental Exchange clearing broker account with daily margin requirements. However, we may enter into financial derivative instruments that contain provisions that require us to maintain an investment-grade credit rating from S&P, Fitch and/or Moody’s. If our credit ratings on our senior unsecured long-term debt were to decline below investment grade, the counterparties to the derivative instruments could request collateralization on derivative instruments in net liability positions.

The counterparties to our derivative contracts typically consist of major energy companies, financial institutions and commercial and industrial end users. This concentration of counterparties may affect our overall exposure to credit risk, either positively or negatively, in that the counterparties may be affected similarly by changes in economic, regulatory or other conditions. Based on our policies, exposures, credit and other reserves, we do not anticipate a material adverse effect on our financial position or results of operations as a result of counterparty nonperformance.

At December 31, 2025, the credit exposure from our derivative assets is with investment-grade companies in the financial services sector.

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E. PROPERTY, PLANT AND EQUIPMENT

The following table sets forth our property, plant and equipment by property type, as of the dates indicated:

						Estimated Useful Lives (Years)						December 31, 2025						December 31, 2024
												(Millions of dollars)
Gathering pipelines and related equipment						3 to 47						$	13,219					$	11,643
Processing and fractionation and related equipment						3 to 40						12,594						12,406
Storage and related equipment						5 to 54						3,770						3,684
Transmission pipelines and related equipment						3 to 87						21,756						21,315
General plant and other						2 to 60						1,171						1,316
Land						—						416						592
Construction work in process						—						2,563						1,318
Property, plant and equipment												55,489						52,274
Accumulated depreciation and amortization												(7,628)						(6,339)
Net property, plant and equipment												$	47,861					$	45,935

The depreciation expense for the years ended December 31, 2025, 2024 and 2023 was $1.4 billion, $1.1 billion and $736 million, respectively.

We incurred costs for construction work in process that had not been paid at December 31, 2025, 2024 and 2023, of $173 million, $179 million and $242 million, respectively. Such amounts are not included in capital expenditures (less AFUDC) on the Consolidated Statements of Cash Flows.

EnLink Controlling Interest Acquisition - In October 2024, we completed the EnLink Controlling Interest Acquisition and acquired property, plant and equipment, which primarily include pipeline and rights of way, pipeline-related equipment, processing plants and fractionators, valued at $11.4 billion.

Medallion Acquisition - In October 2024, we completed the Medallion Acquisition and acquired property, plant and equipment, which primarily include pipeline and pump station equipment, valued at $1.6 billion.

Interstate Natural Gas Pipeline Divestiture - In December 2024, we completed the sale of three of our wholly owned interstate natural gas pipeline systems to DT Midstream, Inc. These assets, which are primarily transmission pipelines and related equipment, had a gross cost basis of $1.3 billion.

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F. GOODWILL AND INTANGIBLE ASSETS

Goodwill - The following table sets forth our goodwill, by segment, for the periods indicated:

			Natural Gas Gathering and Processing						Natural Gas Liquids						Natural Gas Pipelines						Refined Products and Crude						Total
			(Millions of dollars)
Gross goodwill			$	639					$	1,863					$	353					$	5,389					$	8,244
Accumulated impairment losses			(153)						—						—						—						(153)
December 31, 2024			486						1,863						353						5,389						8,091
EnLink Controlling Interest Acquisition adjustment			8						(45)						2						(2)						(37)
Medallion Acquisition adjustment			—						—						—						4						4
December 31, 2025			$	494					$	1,818					$	355					$	5,391					$	8,058

Intangible Assets - Our intangible assets relate primarily to acquired customer relationships from our recent acquisitions and are being amortized on a straight-line basis over a weighted average life of 26 years. Amortization expense for intangible assets was $138 million in 2025, $62 million in 2024 and $33 million in 2023. The amortization expense for each of the next five years is estimated to be $135 million. The following table reflects the gross carrying amount and accumulated amortization of intangible assets as of the dates presented:

			December 31,
			2025						2024
			(Millions of dollars)
Gross intangible assets			$	3,290					$	3,290
Accumulated amortization			(389)						(251)
Intangible assets, net			$	2,901					$	3,039

.

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G. DEBT

The following table sets forth our consolidated debt as of the dates indicated:

			December 31, 2025						December 31, 2024
			(Millions of dollars)
Commercial paper outstanding, bearing a weighted-average interest rate of 3.91% as of December 31, 2025 (a)			$	820					$	—
Senior unsecured obligations:
$250 at 3.2% due March 2025			—						250
$750 at 4.15% due June 2025 (b)			—						422
$400 at 2.2% due September 2025			—						387
$600 at 5.85% due January 2026			—						600
$650 at 5.0% due March 2026			—						650
$500 at 4.85% due July 2026 (b)			491						491
$750 at 5.55% due November 2026			750						750
$500 at 4.0% due July 2027			500						500
$1,250 at 4.25% due September 2027			1,250						1,250
$500 at 5.625% due January 2028 (b)			500						500
$800 at 4.55% due July 2028			800						800
$100 at 6.875% due September 2028			100						100
$750 at 5.650% due November 2028			750						750
$700 at 4.35% due March 2029			700						700
$500 at 5.375% due June 2029 (b)			499						499
$750 at 3.4% due September 2029			714						714
$600 at 4.4% due October 2029			600						600
$850 at 3.1% due March 2030			780						780
$500 at 3.25% due June 2030			500						500
$1,000 at 6.5% due September 2030 (b)			1,000						1,000
$500 at 5.8% due November 2030			500						500
$600 at 6.35% due January 2031			600						600
$1,250 at 4.75% due October 2031			1,250						1,250
$750 at 4.95% due October 2032			750						—
$750 at 6.1% due November 2032			750						750
$1,500 at 6.05% due September 2033			1,500						1,500
$500 at 5.65% due September 2034 (b)			500						500
$1,600 at 5.05% due November 2034			1,600						1,600
$400 at 6.0% due June 2035			400						400
$1,000 at 5.4% due October 2035			1,000						—
$600 at 6.65% due October 2036			600						600
$250 at 6.4% due May 2037			250						250
$600 at 6.85% due October 2037			600						600
$650 at 6.125% due February 2041			650						650
$250 at 4.2% due December 2042			250						250
$400 at 6.2% due September 2043			400						400
$550 at 5.15% due October 2043			550						550
$350 at 5.6% due April 2044 (b)			340						340
$250 at 4.2% due March 2045			250						250
$450 at 5.05% due April 2045 (b)			413						413
$500 at 4.25% due September 2046			500						500
$500 at 5.45% due June 2047 (b)			448						448
$700 at 4.95% due July 2047			407						564
$500 at 4.2% due October 2047			500						500
$1,000 at 5.2% due July 2048			753						919
$500 at 4.85% due February 2049			500						500
$750 at 4.45% due September 2049			380						576
$500 at 4.5% due March 2050			271						443
$800 at 3.95% due March 2050			797						797
$300 at 7.15% due January 2051			300						300
$1,750 at 6.625% due September 2053			1,750						1,750
$1,500 at 5.7% due November 2054			1,480						1,500
$1,250 at 6.25% due October 2055			1,250						—
$800 at 5.85% due November 2064			722						800
Total debt			33,965						33,243
Unamortized debt discounts			(979)						(1,000)
Unamortized debt issuance costs and terminated swaps			(170)						(166)
Current maturities of long-term debt			(1,241)						(1,059)
Short-term borrowings (a)			(820)						—
Long-term debt			$	30,755					$	31,018

(a) - Individual issuances of commercial paper under our commercial paper program generally mature in 90 days or less.

(b) - As of December 31, 2024, amounts represent EnLink and EnLink Partners’ debt acquired in the EnLink Controlling Interest Acquisition on October 15, 2024. At the completion of the EnLink Acquisition on January 31, 2025, ONEOK assumed the outstanding debt of EnLink and EnLink Partners.

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Commercial Paper Program - In September 2025, we increased the size of our commercial paper program to $3.5 billion from $2.5 billion.

$3.5 Billion Credit Agreement - In February 2025, we amended and restated our $2.5 Billion Credit Agreement to increase the size to $3.5 billion, extend the term to February 2030 and make other nonmaterial modifications. Our $3.5 Billion Credit Agreement is a revolving credit facility and contains certain customary conditions for borrowing, as well as customary financial, affirmative and negative covenants. Among other things, these covenants include maintaining a ratio of consolidated net indebtedness to adjusted EBITDA (EBITDA, as defined in our $3.5 Billion Credit Agreement, adjusted for all noncash items and increased for projected EBITDA from certain lender-approved capital expansion projects). In addition, adjusted EBITDA as defined in our $3.5 Billion Credit Agreement allows inclusion of the trailing 12 months of consolidated adjusted EBITDA of an acquired business. In December 2025, we completed the acquisition of a system of gas gathering assets, which allowed us to effectively extend the acquisition adjustment period under our $3.5 Billion Credit Agreement and, as a result, our leverage ratio covenant of 5.5 to 1 was extended through the quarter ending June 30, 2026, after which it will decrease to 5.0 to 1.

The $3.5 Billion Credit Agreement includes a $100 million sublimit for the issuance of standby letters of credit and a $200 million sublimit for swingline loans. Under the terms of the $3.5 Billion Credit Agreement, we may request up to an aggregate $1.0 billion increase in the size of the facility, upon satisfaction of customary conditions, including receipt of commitments from new lenders or increased commitments from existing lenders. The $3.5 Billion Credit Agreement contains provisions for an applicable margin rate and an annual facility fee, both of which adjust with changes in our credit ratings. Borrowings, if any, will accrue at Term SOFR plus an applicable margin based on our credit ratings at the time of determination plus an adjustment of 10 basis points. Under our current credit ratings, the applicable margin on any borrowings would be 110 basis points. We are required to pay an annual facility fee equal to the daily amount of aggregate commitments under the $3.5 Billion Credit Agreement times an applicable rate based on our credit rating at the time of determination. Under our current credit ratings, the applicable rate is 15 basis points. We have the option to request two additional one-year maturity extensions, subject to lender approvals. The $3.5 Billion Credit Agreement also contains various customary events of default, the occurrence of which could result in a termination of the lenders’ commitments and the acceleration of all of our obligations thereunder. As of December 31, 2025, we had no outstanding borrowings, our ratio of consolidated indebtedness to adjusted EBITDA was 4.3 to 1, and we were in compliance with all covenants under our $3.5 Billion Credit Agreement.

EnLink Acquisitions - In October 2024, we completed the EnLink Controlling Interest Acquisition and, as a result, we acquired the EnLink Revolving Credit Facility. The EnLink Revolving Credit Facility, which would have matured in June 2027, was a $1.4 billion unsecured revolving credit facility that included a $500 million letter of credit subfacility. Borrowings under the EnLink Revolving Credit Facility bore interest at Term SOFR plus a Term SOFR spread adjustment of 0.10% per annum and an applicable margin (ranging from 1.125% to 2.00%) or the Base Rate (the highest of the federal funds rate plus 0.50%, one-month Adjusted Term SOFR plus 1.0% or the administrative agent’s prime rate) plus an applicable margin (ranging from 0.125% to 1.00%). Upon closing of the EnLink Acquisition on January 31, 2025, the EnLink Revolving Credit Facility was terminated.

In October 2024, we completed the EnLink Controlling Interest Acquisition and, as a result, we acquired the $500 million EnLink AR Facility. In December 2024, EnLink terminated the EnLink AR Facility, and we entered into an agreement to provide revolving unsecured loans to EnLink through a promissory note at an interest rate of 4.85% at December 31, 2024. This was a floating rate agreement, which bore interest at ONEOK’s current short-term borrowing rate plus 0.25%. At December 31, 2024, we held a promissory note receivable of $510 million, which was eliminated in consolidation. Interest earned from this agreement was not material. Upon closing of the EnLink Acquisition on January 31, 2025, we terminated the agreement to provide revolving unsecured loans to EnLink through a promissory note.

Senior Unsecured Obligations - All notes are senior unsecured obligations, ranking equally in right of payment with all of our existing and future unsecured senior indebtedness, and are structurally subordinate to any of the existing and future debt and other liabilities of any nonguarantor subsidiaries.

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Debt Issuances - We completed the following underwritten public offerings for the periods presented:

			2025 (a)						2024 (b)						2023 (c)
			Principal			Interest			Principal			Interest			Principal			Interest
(Millions of dollars, except for percentages)
3 year note									$	1,250		4.25%			$	750		5.55%
5 year note									600			4.4%			750			5.65%
7 year note			$	750		4.95%			1,250			4.75%			500			5.80%
10 year note			1,000			5.4%			1,600			5.05%			1,500			6.05%
30 year note			1,250			6.25%			1,500			5.7%			1,750			6.625%
40 year note									800			5.85%
Total			$	3,000					$	7,000					$	5,250

(a) - The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $2.96 billion. The net proceeds from this offering were partially used to repay our commercial paper outstanding and repay in full at maturity our senior notes due September 2025. The remaining net proceeds from the offering were used for general corporate purposes, including the repurchase and redemption of existing notes.

(b) - The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $6.9 billion. The net proceeds from this offering were used to fund the EnLink Controlling Interest Acquisition and the Medallion Acquisition, purchase additional interests in a Medallion joint venture owned by a separate third party, to pay fees and expenses related to the acquisitions and to repay outstanding indebtedness.

(c) - The net proceeds, after deducting underwriting discounts, commissions and offering expenses, were $5.2 billion. The net proceeds were used to fund the cash consideration and other costs related to the Magellan Acquisition.

Debt Extinguishments - We completed the following debt extinguishments for the periods presented:

2025						2024						2023
			Principal						Principal						Principal
(Millions of dollars, except for percentages)
$250 at 3.2% due March 2025			$	250		$500 at 2.75% due September 2024			$	484		$500 at 7.5% due September 2023 (a)			$	500
$750 at 4.15% due June 2025			422			$500 at 4.9% due March 2025 (a)			500			$425 at 5.0% due September 2023 (a)			425
$400 at 2.2% due September 2025			387			Guardian Term Loan Agreement			120			Open Market Repurchases (c)			322
$600 at 5.85% due January 2026 (a)			600			Viking Term Loan Agreement			60
$650 at 5.0% due March 2026 (a)			650			EnLink Revolving Credit Facility			465
Open Market Repurchases (b)			789			EnLink AR Facility			374
Total			$	3,098					$	2,003					$	1,247

(a) - Amounts redeemed at 100% of principal plus accrued and unpaid interest.

(b) - In 2025, we repurchased in the open market certain of our senior notes in the principal amount of $789 million for an aggregate repurchase price of $681 million, including accrued and unpaid interest. In connection with these open market repurchases, we recognized $106 million of net gains on extinguishment of debt which is included in other income, net in our Consolidated Statement of Income for the year ended December 31, 2025.

(c) - In 2023, we repurchased in the open market certain of our senior notes in the principal amount of $322 million for an aggregate repurchase price of $280 million, including accrued and unpaid interest. In connection with these open market repurchases, we recognized $41 million of net gains on extinguishment of debt which is included in other income, net in our Consolidated Statement of Income for the year ended December 31, 2023.

The aggregate maturities of long-term debt outstanding and interest payments on total debt outstanding as of December 31, 2025, for the years 2026 through 2030 are shown below:

						Senior Unsecured Obligations																		Interest Obligations on Debt						Total
						(Millions of dollars)
2026						$	1,241																	$	1,739					$	2,980
2027						$	1,750																	$	1,668					$	3,418
2028						$	2,150																	$	1,566					$	3,716
2029						$	2,513																	$	1,451					$	3,964
2030						$	2,780																	$	1,341					$	4,121

Compliance with Debt Covenants - As of December 31, 2025, we were in compliance with the covenants contained in our various debt agreements.

Other - We amortize premiums, discounts and expenses incurred in connection with the issuance of long-term debt consistent with the terms of the respective debt instrument.

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Debt Guarantees - At the completion of the EnLink Acquisition on January 31, 2025, ONEOK assumed the outstanding debt of EnLink and EnLink Partners (the “Assumed Debt”). EnLink and EnLink Partners were released as primary obligors from all debt obligations under the Assumed Debt, but each entity provided a guarantee for our and ONEOK Partners’ indebtedness to the holders of each series of outstanding securities, including for the Assumed Debt.

ONEOK, ONEOK Partners, the Intermediate Partnership, Magellan, EnLink and EnLink Partners have cross guarantees in place for ONEOK’s and ONEOK Partners’ indebtedness.

H. EQUITY

Noncontrolling Interests - As of December 31, 2025, noncontrolling interests in our Consolidated Balance Sheets related to Ascension and MBTC Pipeline. On February 4, 2025, we announced a definitive agreement to form the MBTC Pipeline joint venture, of which we own 80%. As a result of the Delaware Basin JV Acquisition and the EnLink Acquisition, these entities are now wholly owned subsidiaries and are no longer recorded as noncontrolling interests in our Consolidated Balance Sheets as of December 31, 2025.

In October 2024, we completed the EnLink Controlling Interest Acquisition, acquiring GIP’s interest in EnLink consisting of approximately 43% of the outstanding EnLink Units. In connection with the EnLink Controlling Interest Acquisition, we recorded noncontrolling interests with a fair value of $5.1 billion representing the approximately 57% of outstanding EnLink Units we did not own, the Series B Preferred Units and partially owned consolidated subsidiaries of EnLink.

As of December 31, 2024, included within noncontrolling interests are Series B Preferred Units, which were issued under EnLink Partners’ partnership agreement and represent noncontrolling ownership interests in EnLink Partners. EnLink Partners was a controlled subsidiary of EnLink in which EnLink owned all of the outstanding common units. Series B Preferred Units were exchangeable for EnLink Units in an amount equal to the number of outstanding Series B Preferred Units multiplied by an exchange ratio of 1.15, subject to certain adjustments. The exchange was subject to our option to pay cash instead of issuing additional EnLink common units.

As of December 31, 2024, $515 million of noncontrolling interest on our Consolidated Balance Sheets related to Series B Preferred Units, and there were 27.4 million units outstanding. There were no Series B Preferred Units converted or redeemed during the ownership period of October 15, 2024, through December 31, 2024. Distributions made on Series B Preferred Units were not material.

As of December 31, 2024, EnLink owned a 50.1% interest in the Delaware Basin JV, which owns processing facilities located in the Delaware Basin in Texas. Noncontrolling interests included the other owner’s minority interest in the Delaware Basin JV. As of December 31, 2024, $684 million of noncontrolling interests on our Consolidated Balance Sheets related to the Delaware Basin JV and the other partially owned consolidated subsidiary of EnLink was not material.

Series A and B Convertible Preferred Stock - There are no shares of Series A or Series B Preferred Stock currently issued or outstanding.

EnLink Series C Preferred Units - Series C Preferred Units represented noncontrolling ownership interests in EnLink Partners. In September 2024, EnLink gave notice to redeem all of its outstanding Series C Preferred Units, and reclassified the obligation to a liability on their Consolidated Balance Sheets. On October 17, 2024, EnLink redeemed all outstanding Series C Preferred Units at $1,000 per Series C Preferred Unit, plus $8.28 per Series C Preferred Unit of unpaid distributions, for $365 million with proceeds received from borrowings under the EnLink Revolving Credit Facility. As of December 31, 2024, there were no remaining Series C Preferred Units outstanding.

Equity Issuances - On May 28, 2025, we completed the Delaware Basin JV Acquisition. Pursuant to the purchase agreement, we issued approximately 4.9 million shares of ONEOK common stock to the seller with a fair value of $391 million as of the closing date.

On January 31, 2025, we completed the EnLink Acquisition. Pursuant to the EnLink Merger Agreement, each publicly held common unit of EnLink was exchanged for a fixed ratio of 0.1412 shares of ONEOK common stock, including EnLink Units that were exchanged for all previously outstanding Series B Preferred Units immediately prior to closing. We issued 41 million shares of common stock with a fair value of $4.0 billion. There are no remaining Series B Preferred Units outstanding.

In September 2023, we completed the Magellan Acquisition. Pursuant to the Magellan Merger Agreement, each common unit of Magellan was exchanged for a fixed ratio of 0.667 shares of ONEOK common stock and $25.00 of cash. We issued

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approximately 135 million shares of common stock, with a fair value of approximately $9.0 billion as of the closing date of the Magellan Acquisition.

We have an “at-the-market” equity program for the offer and sale from time to time of our common stock up to an aggregate offering price of $1.0 billion. The program allows us to offer and sell common stock at prices we deem appropriate through a sales agent, in forward sales transactions through a forward seller or directly to one or more of the program’s managers acting as principals. Sales of our common stock may be made by means of ordinary brokers’ transactions on the NYSE, in block transactions or as otherwise agreed to between us and the sales agent. We are under no obligation to offer and sell common stock under the program. As of December 31, 2025, no shares have been sold through our “at-the-market” program.

Share Repurchase Program - In January 2024, our Board of Directors authorized a share repurchase program to buy up to $2.0 billion of our outstanding common stock. We expect shares to be acquired from time to time in open market transactions or through privately negotiated transactions at our discretion, subject to market conditions and other factors. The program will terminate upon completion of the repurchase of the $2.0 billion of common stock or on January 1, 2029, whichever occurs first. For the year ended December 31, 2025, we repurchased $62 million of our outstanding common stock under the program with cash on hand. For the year ended December 31, 2024, we repurchased $172 million of our outstanding common stock under the program with cash on hand and short-term borrowings.

Dividends - Holders of our common stock share equally in any common stock dividends declared by our Board of Directors. Dividends paid totaled $2.6 billion, $2.3 billion and $1.8 billion for 2025, 2024 and 2023, respectively. The following table sets forth the quarterly dividends per share paid on our common stock in the periods indicated:

						Years Ended December 31,
						2025						2024						2023
First Quarter						$	1.03					$	0.99					$	0.955
Second Quarter						1.03						0.99						0.955
Third Quarter						1.03						0.99						0.955
Fourth Quarter						1.03						0.99						0.955
Total						$	4.12					$	3.96					$	3.82

Additionally, a quarterly common stock dividend of $1.07 per share ($4.28 per share on an annualized basis) was declared for shareholders of record at the close of business on February 2, 2026, and paid on February 13, 2026.

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I. VARIABLE INTEREST ENTITIES

Consolidated Variable Interest Entities (VIEs) - As of December 31, 2024, we consolidated EnLink, Delaware Basin JV and Ascension VIEs. As a result of the Delaware Basin JV Acquisition and the EnLink Acquisition, these respective entities are no longer considered VIEs.

As of December 31, 2025, we consolidated the following VIEs:

MBTC Pipeline - On February 4, 2025, we announced a definitive agreement with MPLX LP to form the MBTC Pipeline joint venture, which will construct and operate a 24-inch pipeline from our Mont Belvieu, Texas, storage facility to a new liquified petroleum gas export terminal in Texas City, Texas. We own an 80% interest in MBTC Pipeline, and we are the operator. MBTC Pipeline is a VIE because the nonmanaging member does not have substantive rights (except in the case of default and other triggering events) to remove the managing member or participating rights over the managing member. As the managing member, we are the primary beneficiary because we control the decisions that most significantly impact MBTC Pipeline.

Ascension - We own a 50% interest in Ascension, which owns an NGL transmission pipeline that connects our Riverside fractionator to the other owner’s refinery. Ascension is a VIE because the nonmanaging member does not have substantive rights (except in the case of default and other triggering events) to remove us as the managing member. They also do not have the ability to participate or block our decisions as the managing member, which makes us the primary beneficiary because we control the decisions that most significantly impact Ascension.

As of December 31, 2025, the assets and liabilities of our consolidated VIEs were not material. The following table presents the balance sheet information for the assets and liabilities that are only for the use or obligation of our consolidated VIEs, which were included in our Consolidated Balance Sheets as of December 31, 2024:

						December 31, 2024
						(Millions of dollars)
Assets:
Cash and cash equivalents						$	46
Accounts receivable, net						735
Inventories						54
Other current assets						39
Net property, plant and equipment						11,397
Investments in unconsolidated affiliates						317
Goodwill						2,717
Intangible assets, net						1,047
Other assets						134

Liabilities:
Current maturities of long-term debt						$	422
Accounts payable						639
Commodity imbalances						10
Accrued interest						73
Other current liabilities						90
Long-term debt, excluding current maturities						4,693
Deferred income taxes						2,041
Other deferred credits						97

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J. EARNINGS PER SHARE

The following tables set forth the computation of basic and diluted EPS for the periods indicated:

			Year Ended December 31, 2025
			Income						Shares						Per Share Amount
			(Millions, except per share amounts)
Basic EPS
Net income attributable to ONEOK available for common stock			$	3,393					624.8						$	5.43
Diluted EPS
Effect of dilutive securities			—						1.1
Net income attributable to ONEOK available for common stock and common stock equivalents			$	3,393					625.9						$	5.42

			Year Ended December 31, 2024
			Income						Shares						Per Share Amount
			(Millions, except per share amounts)
Basic EPS
Net income attributable to ONEOK available for common stock			$	3,034					584.6						$	5.19
Diluted EPS
Effect of dilutive securities			—						1.9
Net income attributable to ONEOK available for common stock and common stock equivalents			$	3,034					586.5						$	5.17

			Year Ended December 31, 2023
			Income						Shares						Per Share Amount
			(Millions, except per share amounts)
Basic EPS
Net income available for common stock			$	2,658					484.3						$	5.49
Diluted EPS
Effect of dilutive securities			—						1.1
Net income available for common stock and common stock equivalents			$	2,658					485.4						$	5.48

K. SHARE-BASED PAYMENTS

Our Equity Incentive Plan (EIP) provides for the granting of stock-based compensation to eligible employees and non-employee directors, including restricted stock units, performance units, director stock awards and other awards. In May 2025, our shareholders approved the 2025 Equity Incentive Plan (2025 EIP), which replaced the EIP approved by our shareholders in 2018. All new equity awards are issued under the 2025 EIP. There were 19.1 million shares of common stock authorized for issuance under the 2025 EIP and at December 31, 2025, we had 18.6 million shares available for issuance. This calculation of available shares reflects shares issued and estimated shares expected to be issued upon vesting of outstanding awards granted under the 2025 EIP, excluding estimated forfeitures expected to be returned to the plan.

EnLink Acquisitions - As discussed in Note B, we completed the EnLink Controlling Interest Acquisition on October 15, 2024. EnLink had previously issued restricted incentive units and performance units that vest at the end of a designated period, typically three years. The fair value of these awards attributable to pre-combination service was allocated to consideration transferred and was included as part of the purchase price. The portion attributable to post-combination service is being recognized as compensation expense on a straight-line basis over the remaining vesting period of the awards. Upon completion of the EnLink Acquisition on January 31, 2025, each outstanding unit-based award was converted into a restricted stock unit with respect to shares of our common stock and measured at their acquisition date fair value as if they were vested and issued on the acquisition date. Converted restricted stock unit awards accrue dividend equivalents that are paid out in cash quarterly.

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Magellan Acquisition - As discussed in Note B, we completed the Magellan Acquisition on September 25, 2023. Prior to the acquisition, Magellan had previously issued unit-based awards consisting of time-vested phantom units and performance phantom units, that vested at the end of a designated period, typically three years. Pursuant to the terms of the Magellan Merger Agreement, each outstanding unit-based award was converted into a restricted stock unit with respect to shares of our common stock and measured at their acquisition date fair value as if they were vested and issued on the acquisition date. The fair value attributable to pre-combination service was allocated to consideration transferred and was included as part of the purchase price. The portion attributable to post-combination service is being recognized as compensation expense on a straight-line basis over the remaining vesting period of the awards. Converted restricted stock unit awards accrue dividend equivalents that are paid out in cash at vesting.

Restricted Stock Units - We have granted restricted stock units to key employees that vest at the end of a designated period, typically three years, and entitle the grantee to receive shares of our common stock. Restricted stock unit awards are measured at fair value as if they were vested and issued on the grant date and adjusted for estimated forfeitures. Restricted stock unit awards accrue dividend equivalents in the form of additional restricted stock units prior to vesting. Compensation expense is recognized on a straight-line basis over the vesting period of the award.

Performance Unit Awards - We have granted performance unit awards to key employees that vest at the end of a three-year period. Upon vesting, a holder of outstanding performance units is entitled to receive a number of shares of our common stock equal to a percentage (0% to 200%) of the performance units granted, based on our total shareholder return over the performance period, compared with the total shareholder return of a peer group of other energy companies over the same period. Performance unit awards are measured at fair value on the grant date based on a Monte Carlo model and adjusted for estimated forfeitures. Performance unit awards accrue dividend equivalents in the form of additional performance units prior to vesting. Compensation expense is recognized on a straight-line basis over the vesting period of the award.

Stock Compensation for Non-Employee Directors - The 2025 EIP provides for the granting of director stock awards and other awards to non-employee directors, up to $1.0 million per year for each such director when combined with any cash fees.

General - For all awards outstanding, we used a 3% forfeiture rate based on historical forfeitures under our share-based payment plans. We currently use treasury stock to satisfy our share-based payment obligations.

Compensation expense, exclusive of those recognized within transaction costs, for our share-based payment plans was $92 million, $102 million and $63 million during 2025, 2024 and 2023, respectively, before related tax benefits of $31 million, $36 million and $14 million, respectively.

Restricted Stock Unit Activity - As of December 31, 2025, we had $87 million of total unrecognized compensation cost related to our nonvested restricted stock unit awards, which is expected to be recognized over a weighted-average period of 1.9 years. The following tables set forth activity and various statistics for our restricted stock unit awards:

						Number of Units						Weighted Average Price
Nonvested December 31, 2024						1,360,122						$	68.71
Granted (a)						1,605,626						$	88.80
Released to participants (b)						(938,789)						$	75.33
Forfeited (b)						(77,622)						$	85.70
Nonvested December 31, 2025						1,949,337						$	81.40

(a) - Included 480,280 unvested restricted stock unit awards converted in conjunction with the EnLink Acquisition.

(b) - Included 348,019 restricted stock unit awards released to participants and forfeited in conjunction with the EnLink Acquisition.

						2025						2024						2023
Weighted-average grant date fair value (per share)						$	88.80					$	75.42					$	66.50
Grant date fair value of units granted (millions of dollars)						$	143					$	39					$	111

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Performance Unit Activity - As of December 31, 2025, we had $39 million of total unrecognized compensation cost related to the nonvested performance unit awards, which is expected to be recognized over a weighted-average period of 1.7 years. The following tables set forth activity and various statistics related to the performance unit awards and the assumptions used in the valuations at the respective grant dates:

						Number of Units						Weighted Average Price
Nonvested December 31, 2024						1,099,699						$	84.25
Granted						449,020						$	80.55
Released to participants						(332,706)						$	79.21
Forfeited						(50,905)						$	84.55
Nonvested December 31, 2025						1,165,108						$	84.25

						2025						2024						2023
Volatility (a)						27.17%						29.00%						63.30%
Dividend yield						4.15%						5.40%						5.75%
Risk-free interest rate						4.30%						4.46%						4.43%

(a) - Volatility was based on historical volatility over three years using daily stock price observations.

						2025						2024						2023
Weighted-average grant date fair value (per share)						$	80.55					$	85.69					$	87.46
Grant date fair value of units granted (millions of dollars)						$	36					$	39					$	32

Employee Stock Purchase Plan - We have reserved a total of 13.1 million shares of common stock for issuance under our Employee Stock Purchase Plan (the ESPP). Subject to certain exclusions, all employees are eligible to participate in the ESPP. Employees can choose to have up to 10% of their base pay withheld from each paycheck during the offering period to purchase our common stock, subject to the terms and limitations of the plan. The purchase price of the stock is 85% of the lower of its grant date or exercise date market price. Approximately 58%, 59% and 69% of employees participated in the plan in 2025, 2024 and 2023, respectively. Under the plan, we sold 356,745 shares at a weighted average of $65.34 per share in 2025, 275,874 shares at a weighted average of $64.38 per share in 2024 and 236,108 shares at a weighted average of $52.70 per share in 2023.

Employee Stock Award Program - Under our Employee Stock Award Program (the ESAP), we issued, for no monetary consideration, to all eligible employees one share of our common stock when the per-share closing price of our common stock on the NYSE is at or above each one-dollar increment above its previous high closing price. We authorized a total of 900,000 shares of common stock under the ESAP. The ESAP terminated as of November 7, 2024, and no additional grants were made under the program after such date. In May 2025, our shareholders approved the 2025 Employee Stock Award Program (the 2025 ESAP), which issues shares of our common stock in the same manner as the ESAP and permits our Board of Directors to issue additional shares of our common stock in its discretion. A total of 700,000 shares of common stock were authorized for issuance under the 2025 ESAP. Shares issued to employees under these programs during 2025 and 2024 totaled 66,916 and 127,825, respectively. Employees have received awards through the $117 milestone. No shares were issued to employees under these programs in 2023.

Deferred Compensation Plan for Non-Employee Directors - Our Deferred Compensation Plan for Non-Employee Directors provides our non-employee directors the option to defer all or a portion of their compensation for their service on our Board of Directors. Under the plan, directors may elect either a cash deferral option or a phantom stock option. Under the cash deferral option, directors may elect to defer the receipt of all or a portion of their annual retainer fees (other than their stock retainer fees), which will be credited with interest during the deferral period. Under the phantom stock option, directors may defer all or a portion of their annual retainer fees and receive such fees on a deferred basis in the form of shares of common stock under our EIP or 2025 EIP, which earn the equivalent of dividends declared on our common stock. Shares are distributed to non-employee directors at the fair market value of our common stock at the date of distribution.

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L. EMPLOYEE BENEFIT PLANS

Retirement and Other Postretirement Benefit Plans

ONEOK Retirement Plan - We maintain the ONEOK Retirement Plan, a defined benefit pension plan covering certain legacy ONEOK employees, which closed to new participants in 2005. In addition, we have a supplemental executive retirement plan for the benefit of certain officers who participate in the ONEOK Retirement Plan. Our supplemental executive retirement plan is closed to new participants. We fund our defined benefit pension plan at a level needed to maintain or exceed the minimum funding levels required by the Employee Retirement Income Security Act of 1974, as amended.

Magellan Retirement Plans - As a result of the Magellan Acquisition in 2023, we assumed two defined benefit pension plans covering certain legacy Magellan employees, including the Magellan Pension Plan, which closed to new participants upon the closing of the acquisition, and the Magellan Pension Plan for USW Employees, which closed to new participants in January 2024. We fund these defined benefit pension plans at a level needed to maintain or exceed the minimum funding levels required by the Employee Retirement Income Security Act of 1974, as amended.

Other Postretirement Benefit Plans - We sponsor health and welfare plans that provide postretirement medical and life insurance benefits to certain legacy ONEOK employees hired prior to 2017 and certain legacy Magellan employees who retire after a specified age with at least five years of service and satisfy certain other conditions. The postretirement medical plan for pre-Medicare participants is contributory, with retiree contributions adjusted periodically, and contains other cost-sharing features such as deductibles and coinsurance. The postretirement medical plan for Medicare-eligible participants is an account-based plan under which participants may elect to purchase private insurance policies under a private exchange and/or seek reimbursement of other eligible medical expenses and is not available to legacy Magellan employees.

Obligations and Funded Status - The following table sets forth our retirement and other postretirement benefit plans benefit obligations and fair value of plan assets for the periods indicated:

						Retirement Benefits												Other Postretirement Benefits
						December 31,												December 31,
						2025						2024						2025						2024
Change in benefit obligation						(Millions of dollars)
Benefit obligation, beginning of period						$	689					$	702					$	46					$	51
Service cost						15						21						—						—
Interest cost						39						37						3						2
Plan participants’ contributions						—						—						1						1
Actuarial loss (gain)						2						(35)						(1)						(5)
Benefits paid						(38)						(36)						(4)						(3)
Benefit obligation, end of period (a)						707						689						45						46
Change in plan assets
Fair value of plan assets, beginning of period						535						554						15						16
Actual return on plan assets						60						12						2						1
Employer contributions						29						5						—						—
Plan participants’ contributions						—						—						1						1
Benefits paid						(38)						(36)						(4)						(3)
Fair value of plan assets, end of period (b)						586						535						14						15
Balance at December 31						$	(121)					$	(154)					$	(31)					$	(31)
Current liabilities						$	(5)					$	(5)					$	—					$	—
Noncurrent liabilities						(116)						(149)						(31)						(31)
Balance at December 31						$	(121)					$	(154)					$	(31)					$	(31)

(a) - The benefit obligation for Retirement Benefits at December 31, 2025 and 2024, included the supplemental executive retirement plan obligation.

(b) - Fair value of plan assets for Retirement Benefits excluded the assets of our supplemental executive retirement plan, which totaled $90 million and $92 million at December 31, 2025 and 2024, respectively, and are included in other assets on the Consolidated Balance Sheets. These assets are maintained in a rabbi trust and are not treated as assets of the supplemental executive retirement plan.

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The accumulated benefit obligation for our retirement plans was $648 million and $628 million at December 31, 2025 and 2024, respectively.

The components of net periodic benefit cost and related assumptions, and amounts recognized in other comprehensive income related to our retirement and other postretirement benefit plans are not material. The balance in accumulated other comprehensive loss at December 31, 2025 and 2024, was $46 million and $58 million, respectively. This balance is expected to be amortized over the average remaining service period of employees participating in these plans.

Actuarial Assumptions - The following table sets forth the weighted-average assumptions used to determine benefit obligations for retirement and other postretirement benefits for the periods indicated:

						Retirement Benefits												Other Postretirement Benefits
						December 31,												December 31,
						2025						2024						2025						2024
Discount rate						5.70%						5.80%						5.70%						5.80%
Compensation increase rate						3.48%						3.65%						NA						NA
Interest credit rating (a)						4.84%						4.78%						NA						NA

(a) - This actuarial assumption is only applicable to the pension plans assumed with the Magellan Acquisition.

We determine our discount rates annually utilizing portfolios of high-quality bonds matched to the estimated benefit cash flows of our retirement and other postretirement benefit plans. Bonds selected to be included in the portfolios are only those rated by S&P or Moody’s as an AA or Aa2 rating or better and exclude callable bonds, bonds with less than a minimum issue size, yield outliers and other filtering criteria to remove unsuitable bonds.

Plan Assets - Our investment strategy is to invest plan assets in accordance with sound investment practices that emphasize long-term fundamentals. The goal of this strategy is to maximize investment returns while managing risk in order to meet the plan’s current and projected financial obligations. The investment allocation for our ONEOK Retirement Plan follows a glide path approach of liability-driven investing that shifts a higher portfolio weighting to fixed income as the plan’s funded status increases. A majority of the assets of the Magellan Pension Plan and the Magellan Pension Plan for USW Employees are allocated to fixed income securities and invested to match the duration of the plans’ short, intermediate and long-term liabilities, with the remaining amount allocated to equity securities. Our pension plans utilize a diversified mix of investments that may include domestic and international equities, short, intermediate and long-term corporate and government obligations, real estate and hedge funds. The combined target allocation for the assets of our pension plans as of December 31, 2025, is as follows:

Domestic and international equities						30		%
Long duration fixed income						58		%
Return-seeking credit						4		%
Hedge funds						5		%
Real estate funds						3		%
Total						100		%

As part of our risk management for the plans, minimums and maximums have been set for each of the asset classes listed above.

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The fair value of the plan assets for our other postretirement benefit plans as of December 31, 2025, are not material. The following tables set forth the plan assets by fair value category as of the measurement date for our defined benefit pension plans:

						Pension Benefits
						December 31, 2025
Asset Category						Level 1						Level 2						Level 3						Subtotal						Measured at NAV (d)						Total
						(Millions of dollars)
Investments:
Equity securities						$	73					$	—					$	—					$	73					$	—					$	73
Cash and money market funds						8						—						—						8						—						8
Government obligations						34						—						—						34						—						34
Corporate obligations						122						—						—						122						—						122
Common/collective trusts
Equity securities (a)						—						—						—						—						102						102
Real estate funds						—						—						—						—						17						17
Government obligations						—						—						—						—						66						66
Corporate obligations (b)						—						—						—						—						130						130
Short-term investments						—						—						—						—						6						6
Other investments (c)						—						—						—						—						28						28
Fair value of plan assets						$	237					$	—					$	—					$	237					$	349					$	586

(a) - This category represents securities of the respective market sector from diverse industries.

(b) - This category represents bonds from diverse industries.

(c) - This category represents alternative investments in limited partnerships, which can be redeemed with a 30-day notice with no further restrictions. There were no unfunded capital commitments. These limited partnerships invest through multi-strategy programs in broadly diversified portfolios of private investment funds, hedge funds and/or separate accounts to seek equity-like returns with low market correlation, reduced volatility and limited risk.

(d) - Plan asset investments measured at fair value using the net asset value per share.

						Pension Benefits
						December 31, 2024
Asset Category						Level 1						Level 2						Level 3						Subtotal						Measured at NAV (d)						Total
						(Millions of dollars)
Investments:
Equity securities						$	64					$	—					$	—					$	64					$	—					$	64
Cash and money market funds						7						—						—						7						—						7
Government obligations						36						—						—						36						—						36
Corporate obligations						101						—						—						101						—						101
Common/collective trusts
Equity securities (a)						—						—						—						—						107						107
Real estate funds						—						—						—						—						18						18
Government obligations						—						—						—						—						50						50
Corporate obligations (b)						—						—						—						—						118						118
Short-term investments						—						—						—						—						5						5
Other investments (c)						—						—						—						—						29						29
Fair value of plan assets						$	208					$	—					$	—					$	208					$	327					$	535

(a) - This category represents securities of the respective market sector from diverse industries.

(b) - This category represents bonds from diverse industries.

(c) - This category represents alternative investments in limited partnerships, which can be redeemed with a 30-day notice with no further restrictions. There were no unfunded capital commitments. These limited partnerships invest through multi-strategy programs in broadly diversified portfolios of private investment funds, hedge funds and/or separate accounts to seek equity-like returns with low market correlation, reduced volatility and limited risk.

(d) - Plan asset investments measured at fair value using the net asset value per share.

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Contributions - During 2025, we contributed $9 million to our ONEOK Retirement Plan, $17 million to our Magellan Pension Plan and $3 million to our Magellan Pension Plan for USW Employees, all of which were related to the 2024 plan year. We do not expect contributions to our defined benefit pension plans to be material in 2026. We do not expect to make any contributions to other postretirement benefit plans in 2026.

Pension and Other Postretirement Benefit Payments - Benefit payments for our defined benefit pensions and other postretirement benefit plans for the period ending December 31, 2025, were $38 million and $4 million, respectively. The following table sets forth the defined benefit pension and other postretirement benefits payments expected to be paid in 2026 through 2035:

						Pension Benefits						Other Postretirement Benefits
Benefits to be paid in:						(Millions of dollars)
2026						$	47					$	4
2027						$	47					$	4
2028						$	49					$	4
2029						$	52					$	4
2030						$	53					$	4
2031 through 2035						$	280					$	17

The expected benefits to be paid are based on the same assumptions used to measure our benefit obligation at December 31, 2025, and include estimated future employee service.

Other Employee Benefit Plans

401(k) Plan - The ONEOK 401(k) Plan covers all employees, and employee contributions are discretionary. We match 100% of employee 401(k) Plan contributions up to 6% of each participant’s eligible compensation, subject to certain conditions and limits. We also make profit-sharing contributions under our 401(k) Plan for employees who do not participate in our defined benefit pension plans. Effective January 1, 2025, quarterly profit-sharing contributions increased to 6% from 1% of each profit-sharing participant’s eligible compensation during the quarter. We may also make annual discretionary profit-sharing contributions of up to 2% of eligible compensation. Our contributions made to the plan, including profit-sharing contributions, were $128 million, $66 million and $44 million in 2025, 2024 and 2023, respectively.

EnLink terminated the EnLink 401(k) Plan effective January 30, 2025, prior to the closing of the EnLink Acquisition. Legacy EnLink employees were permitted to roll their EnLink 401(k) Plan account balance to the ONEOK 401(k) Plan, an individual retirement account or take a distribution. The EnLink 401(k) Plan was liquidated and closed in December 2025.

Medallion terminated the Medallion 401(k) Plan effective October 30, 2024, prior to the closing of the Medallion Acquisition on October 31, 2024. Legacy Medallion employees were permitted to roll their Medallion 401(k) Plan account balance to the ONEOK 401(k) Plan or an individual retirement account or take a distribution. The Medallion 401(k) Plan was liquidated and closed in September 2025.

Magellan terminated the Magellan 401(k) Plan effective September 24, 2023, prior to the closing of the Magellan Acquisition. Legacy Magellan employees were given the option to roll their Magellan 401(k) Plan account balance to the ONEOK 401(k) Plan or an individual retirement account or take a distribution. The Magellan 401(k) Plan was liquidated and closed in September 2024.

Nonqualified Deferred Compensation Plan - The 2020 Nonqualified Deferred Compensation Plan and its predecessor nonqualified deferred compensation plans (collectively, the NQDC Plan) provide a select group of management and highly compensated employees, as approved by our chief executive officer, with the option to defer portions of their compensation and receive notional employer contributions that generally are not available due to limitations on employer and employee contributions to qualified defined contribution plans under federal tax laws. Our investments which are included in other assets on the Consolidated Balance Sheets related to the NQDC Plan were not material. These investments are maintained in a rabbi trust. Our contributions to the plan were not material.

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M. INCOME TAXES

The following table sets forth our provision for income taxes for the periods indicated:

			Years Ended December 31,
			2025						2024						2023
			(Millions of dollars)
Current tax expense (benefit)
Federal			$	49					$	89					$	(3)
State			22						20						12
Total current tax expense			71						109						9
Deferred tax expense
Federal			888						792						739
State			69						97						90
Total deferred tax expense			957						889						829
Total provision for income taxes			$	1,028					$	998					$	838

The following table is a reconciliation of our income tax provision for the periods indicated:

			Years Ended December 31,
			2025												2024												2023
			(Millions of dollars, except for percentages)
									(b)												(b)												(b)
Income before income taxes			$	4,490											$	4,110											$	3,497
Federal statutory income tax rate			21.0		%										21.0		%										21.0		%
Provision for federal income taxes			943						21.0		%				863						21.0		%				734						21.0		%
State income taxes, net of federal tax benefit (a)			91						2.0		%				125						3.0		%				102						2.9		%
Nontaxable or nondeductible items			(6)						(0.1)		%				3						0.1		%				(1)						—		%
Other, net			—						—		%				7						0.2		%				3						0.1		%
Income tax provision			$	1,028					22.9		%				$	998					24.3		%				$	838					24.0		%

(a) - Our operations are primarily apportioned across Oklahoma, Texas, Kansas and North Dakota for state income tax purposes.

(b) - Represents percent of income before income taxes.

The following table sets forth cash paid for income taxes, net of refunds, for the periods indicated:

			Years Ended December 31,
			2025						2024						2023
			(Millions of dollars)
Federal			$	52					$	85					$	27
State			22						17						10
Total cash paid for income taxes, net of refunds			$	74					$	102					$	37

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The following table sets forth the tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities as of the dates indicated:

						December 31, 2025						December 31, 2024
Deferred tax assets						(Millions of dollars)
Employee benefits and other accrued liabilities						$	98					$	99
Federal net operating loss						2,570						2,818
Federal tax credit						6						—
State net operating loss and benefits						546						515
Derivative instruments						—						15
Interest expense limitation						237						407
Other						17						39
Total deferred tax assets						3,474						3,893
Valuation allowance for state net operating loss and tax credits
Carryforward expected to expire prior to utilization						(267)						(252)
Net deferred tax assets						3,207						3,641
Deferred tax liabilities
Excess of tax over book depreciation						92						58
Derivative instruments						5						—
Investment in partnerships (a)						9,459						9,034
Total deferred tax liabilities						9,556						9,092
Net deferred tax liabilities						$	6,349					$	5,451

(a) Due primarily to excess of tax over book depreciation.

On January 31, 2025, we completed the EnLink Acquisition by acquiring all of the remaining and outstanding publicly held EnLink Units. EnLink is now a wholly owned subsidiary and included in our consolidated income tax returns.

As of December 31, 2025, we have federal net operating loss carryforwards of $12.2 billion, which have an indefinite carryforward period. We expect to generate taxable income and utilize these net operating loss carryforwards in future periods. We also have loss and credit carryovers in multiple states, $13.2 billion of which, have an indefinite carryforward period and $1.2 billion of which will expire between 2029 and 2043. We have deferred tax assets related to federal and state net operating loss and credit carryforwards of $3.1 billion and $3.3 billion in 2025 and 2024, respectively. We believe that it is more likely than not that the tax benefits of certain state carryforwards will not be utilized; therefore, we recorded a valuation allowance, which was increased by $15 million, $12 million and $165 million in 2025, 2024 and 2023, respectively, through net income.

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N. UNCONSOLIDATED AFFILIATES

Investments in Unconsolidated Affiliates - The following table sets forth our investments in unconsolidated affiliates as of the dates indicated:

						Net Ownership Interest						December 31, 2025						December 31, 2024
												(Millions of dollars)
BridgeTex (a)						60%						$	504					$	250
Northern Border						50%						444						333
Overland Pass						50%						391						400
Saddlehorn						40%						361						373
Matterhorn (b)						15%						272						248
MVP						25%						228						235
Roadrunner						50%						181						183
Texas City Logistics						50%						162						—
Other						Various						346						294
Investments in unconsolidated affiliates (c)												$	2,889					$	2,316

(a) - In July 2025, we purchased an additional 30% interest in BridgeTex, resulting in a 60% ownership interest.

(b) - As of December 31, 2025, the 15% interest represented ONEOK’s ownership interest in Matterhorn as a result of the EnLink Acquisition on January 31, 2025. As of December 31, 2024, the 15% interest represented EnLink’s ownership interest in Matterhorn.

(c) - Included basis differences of $431 million and $368 million at December 31, 2025, and 2024, respectively, related to property, plant and equipment and equity-method goodwill (Note A).

Equity in Net Earnings from Investments - The following table sets forth our equity in net earnings from investments for the periods indicated:

						Years Ended December 31,
						2025						2024						2023
						(Millions of dollars)
Northern Border						$	105					$	95					$	75
Overland Pass						91						86						56
Saddlehorn (a)						50						50						10
BridgeTex (a)(c)						41						127						(1)
Roadrunner						41						40						43
Matterhorn (b)						24						8						—
MVP (a)						13						14						4
Other						21						19						15
Equity in net earnings from investments						$	386					$	439					$	202

(a) - The year ended December 31, 2023, included equity in net earnings from the period September 25, 2023, through December 31, 2023.

(b) - The year ended December 31, 2024, included equity in net earnings from the period October 15, 2024, through December 31, 2024.

(c) - The year ended December 31, 2024, included equity in net earnings of $88 million on BridgeTex associated with the nonrecurring recognition of deferred revenue.

We incurred expenses in transactions with unconsolidated affiliates of $280 million, $254 million and $132 million for 2025, 2024 and 2023, respectively, primarily related to Overland Pass, Matterhorn and Northern Border. Revenue earned and accounts receivable from, and accounts payable to, our unconsolidated affiliates were not material.

We have agreements with our unconsolidated affiliates which provide that distributions to members are made, primarily, on a pro rata basis according to each member’s ownership interest.

We are the operator of Roadrunner, BridgeTex, MVP and Saddlehorn. In each case, we have operating agreements that provide for reimbursement or payment to us for management services and certain operating costs. Reimbursements and payments included in operating income in our Consolidated Statements of Income for all periods presented were not material.

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In 2025, we, WhiteWater, MPLX LP and Enbridge Inc., through the existing Matterhorn joint venture, announced the new approximately 450-mile, 48-inch Eiger Express Pipeline, designed to transport up to approximately 3.7 Bcf/d of natural gas from the Permian Basin to Katy, Texas. WhiteWater will construct and operate the pipeline. Our total ownership interest in the pipeline will be 25.5%, which includes a 15% interest held directly in the Eiger joint venture with the remainder held through Matterhorn. Our investment in Eiger is accounted for using the equity method as we have the ability to exercise significant influence over the operating and financial policies of Eiger, although we do not have the ability to exercise control.

On July 22, 2025, we completed the BridgeTex Additional Interest Acquisition. Pursuant to the purchase agreement, we paid approximately $270 million in cash, which we funded with short-term borrowings. Following the completion of the transaction, we now have a 60% ownership interest in BridgeTex. Our investment in BridgeTex continues to be accounted for using the equity method as we continue to have the ability to exercise significant influence over the operating and financial policies of BridgeTex, although we do not have the ability to exercise control.

On February 4, 2025, we announced definitive agreements to form joint ventures with MPLX LP to construct a 400 MBbl/d liquified petroleum gas export terminal in Texas City, Texas, and a new 24-inch pipeline from our Mont Belvieu, Texas, storage facility to the new terminal. Texas City Logistics, the export terminal joint venture, is owned 50% by us and 50% by MPLX LP, with MPLX LP constructing and operating the facility. Our investment in Texas City Logistics is accounted for using the equity method as we have the ability to exercise significant influence over the operating and financial policies of Texas City Logistics, although we do not have the ability to exercise control.

In 2025, we made equity contributions to Texas City Logistics and Northern Border of $160 million and $101 million, respectively, which, in combination with equal contributions from our joint venture partners, were primarily used for funding capital projects. In 2024, we acquired an additional 10% interest in Saddlehorn, resulting in a total ownership interest of 40%. In 2023, we made an equity contribution of $105 million to Roadrunner, which, in combination with an equal contribution from our joint venture partner, was used to repay Roadrunner’s outstanding debt. Also in 2023, we made an equity contribution of $91 million to Northern Border, which, in combination with an equal contribution from our joint venture partner, was used to partially repay the outstanding balance of its revolving credit facility and fund capital projects.

O. COMMITMENTS AND CONTINGENCIES

Commitments - The following table sets forth our transportation, volume and storage commitments for the periods indicated:

Commitments						(Millions of dollars)
2026						$	286
2027						272
2028						253
2029						238
2030						229
Thereafter						870
Total						$	2,148

Regulatory, Environmental and Safety Matters - The operation of pipelines, terminals, plants and other facilities for the gathering, processing, fractionation, transportation and storage of products is subject to numerous and complex laws and regulations pertaining to health, safety and the environment. As an owner and/or operator of these facilities, we must comply with laws and regulations that relate to air and water quality, hazardous and solid waste management and disposal, cultural resource protection and other environmental and safety matters. The cost of planning, designing, constructing and operating pipelines, terminals, plants and other facilities must incorporate compliance with these laws, regulations and safety standards. Failure to comply with these laws and regulations may trigger a variety of administrative, civil and potentially criminal enforcement measures, including citizen suits, which can include the assessment of monetary penalties, the imposition of remedial requirements and the issuance of injunctions or restrictions on operation or construction. Management does not believe that, based on currently known information, a material risk of noncompliance with these laws and regulations exists that will adversely affect our consolidated results of operations, financial condition or cash flows.

Legal Proceedings - We are a party to various legal proceedings that have arisen in the normal course of our operations. While the results of these proceedings cannot be predicted with certainty, we believe the reasonably possible losses from such proceedings, individually and in the aggregate, are not material. Additionally, we believe the probable final outcome of such proceedings will not have a material adverse effect on our consolidated results of operations, financial position or cash flows.

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P. LEASES

Lessee activity - The following table sets forth information about our operating lease assets and liabilities included in our Consolidated Balance Sheets as of the dates indicated:

Leases			Location in our Consolidated Balance Sheets						December 31, 2025						December 31, 2024
									(Millions of dollars)
Operating lease assets			Other assets						$	245					$	220
Operating lease liabilities
Current			Other current liabilities						$	54					$	62
Noncurrent			Other deferred credits						183						154
Total operating lease liabilities									$	237					$	216

The weighted average remaining lease term for our operating leases was 11.0 years and 9.1 years at December 31, 2025 and 2024, respectively. The weighted average discount rate for our operating leases was 5.52% and 5.51% at December 31, 2025 and 2024, respectively. Our weighted-average discount rates represent the rate implicit in the lease or our incremental borrowing rate for a term equal to the remaining term of the lease.

The following table sets forth the maturity of our lease liabilities as of December 31, 2025:

												Operating Leases
									(Millions of dollars)
2026												$	61
2027												39
2028												34
2029												29
2030												22
2031 and beyond												130
Total lease payments												315
Less: Interest												78
Present value of lease liabilities												$	237

Our lease costs and supplemental cash flow information related to our leases for the periods ended December 31, 2025 and 2024, are not material.

Q. REVENUES

Unsatisfied Performance Obligations - We do not disclose the value of unsatisfied performance obligations for (i) contracts with an original expected length of one year or less and (ii) variable consideration on contracts for which we recognize revenue at the amount to which we have the right to invoice for services performed.

The following table presents aggregate value allocated to unsatisfied performance obligations as of December 31, 2025, and the amounts we expect to recognize in revenue in future periods, related primarily to firm transportation and storage contracts with remaining contract terms ranging from one month to 20 years:

Expected Period of Recognition in Revenue						(Millions of dollars)
2026						$	1,259
2027						1,162
2028						985
2029						845
2030 and beyond						2,810
Total						$	7,061

The table above excludes variable consideration allocated entirely to wholly unsatisfied performance obligations, wholly unsatisfied promises to transfer distinct goods or services that are part of a single performance obligation and consideration we

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determine to be fully constrained. Information on the nature of the variable consideration excluded and the nature of the performance obligations to which the variable consideration relates can be found in the description of the major contract types discussed in Note A. The amounts we determined to be fully constrained relate to future sales obligations under long-term sales contracts where the value is not known and certain minimum volume agreements, which we consider to be fully constrained until invoiced.

R. SEGMENTS

Segment Descriptions - Our operations are divided into four reportable business segments, as follows:

• our Natural Gas Gathering and Processing segment gathers, compresses, treats, processes and markets natural gas;

• our Natural Gas Liquids segment gathers, treats, fractionates and transports NGLs and stores, markets and distributes Purity NGLs;

• our Natural Gas Pipelines segment transports, stores and markets natural gas; and

• our Refined Products and Crude segment gathers, transports, stores, distributes, blends and markets Refined Products and crude oil.

On October 15, 2024, we completed the EnLink Controlling Interest Acquisition. Our 2024 results include the impact of the EnLink Controlling Interest Acquisition from the period of October 15, 2024, to December 31, 2024, across all four of our existing operating segments. On October 31, 2024, we completed the Medallion Acquisition. Our 2024 results include the impact of the Medallion Acquisition from the period of November 1, 2024, to December 31, 2024, in our Refined Products and Crude segment.

Other and eliminations consist of corporate costs, the operating activities of our headquarters building and related parking facility, the activity of our wholly owned captive insurance company and eliminations necessary to reconcile our reportable segments to our Consolidated Financial Statements.

For the years ended December 31, 2025, and December 31, 2023, revenues from one customer impacting all our segments represented approximately 12% and 11% of our consolidated revenues, respectively. For the year ended December 31, 2024, we had no single customer from which we received 10% or more of our consolidated revenues.

The significant expense categories and amounts included in the table below align with the segment-level information that is regularly provided to the chief operating decision-maker.

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Operating Segment Information - The following tables set forth certain selected financial information for our operating segments for the periods indicated:

Year Ended December 31, 2025			Natural Gas Gathering and Processing						Natural Gas Liquids						Natural Gas Pipelines						Refined Products and Crude						Total Segments
			(Millions of dollars)
Liquids commodity sales			$	4,372					$	15,405					$	—					$	10,631					$	30,408
Residue natural gas sales			2,137						—						1,235						—						3,372
Exchange services and natural gas gathering and processing revenue			1,137						336						—						—						1,473
Transportation and storage revenue			—						258						611						2,291						3,160
Other revenue			38						11						—						117						166
Total revenues (a)			7,684						16,010						1,846						13,039						38,579
Cost of sales and fuel (exclusive of depreciation and operating costs)			(4,617)						(12,533)						(1,005)						(10,171)						(28,326)
Operating costs			(988)						(831)						(231)						(906)						(2,956)
Adjusted EBITDA from unconsolidated affiliates			5						101						244						166						516
Noncash compensation expense and other			54						32						7						49						142
Segment adjusted EBITDA			$	2,138					$	2,779					$	861					$	2,177					$	7,955
Depreciation and amortization			$	(501)					$	(468)					$	(98)					$	(438)					$	(1,505)
Equity in net earnings from investments			$	3					$	91					$	170					$	122					$	386
Investments in unconsolidated affiliates			$	40					$	652					$	929					$	1,263					$	2,884
Total assets			$	16,757					$	20,415					$	4,805					$	25,255					$	67,232
Capital expenditures			$	1,314					$	758					$	237					$	752					$	3,061

(a) - Intersegment revenues are primarily from commodity sales, which are based on the contracted selling price that is generally index-based and settled monthly. Intersegment revenues totaled $4.3 billion for the Natural Gas Gathering and Processing segment, $0.5 billion for the Natural Gas Liquids segment and were not material for the Refined Products and Crude and Natural Gas Pipelines segments.

Year Ended December 31, 2025			Total Segments						Other and Eliminations						Total
			(Millions of dollars)
Reconciliations of total segments to consolidated
Liquids commodity sales			$	30,408					$	(4,842)					$	25,566
Residue natural gas sales			3,372						(60)						3,312
Exchange services and natural gas gathering and processing revenue			1,473						(3)						1,470
Transportation and storage revenue			3,160						(23)						3,137
Other revenue			166						(22)						144
Total revenues (a)			$	38,579					$	(4,950)					$	33,629
Cost of sales and fuel (exclusive of depreciation and operating costs)			$	(28,326)					$	4,953					$	(23,373)
Operating costs			$	(2,956)					$	(7)					$	(2,963)
Depreciation and amortization			$	(1,505)					$	(9)					$	(1,514)
Equity in net earnings from investments			$	386					$	—					$	386
Investments in unconsolidated affiliates			$	2,884					$	5					$	2,889
Total assets			$	67,232					$	(591)					$	66,641
Capital expenditures			$	3,061					$	91					$	3,152

(a) - Substantially all of our revenues are related to contracts with customers.

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Year Ended December 31, 2024			Natural Gas Gathering and Processing						Natural Gas Liquids						Natural Gas Pipelines						Refined Products and Crude						Total Segments
			(Millions of dollars)
Liquids commodity sales			$	3,033					$	14,446					$	—					$	2,258					$	19,737
Residue natural gas sales			1,203						—						137						—						1,340
Exchange services and natural gas gathering and processing revenue			260						500						—						—						760
Transportation and storage revenue			70						207						684						2,082						3,043
Other revenue			23						14						1						120						158
Total revenues (a)			4,589						15,167						822						4,460						25,038
Cost of sales and fuel (exclusive of depreciation and operating costs)			(2,600)						(11,994)						(112)						(1,949)						(16,655)
Operating costs			(603)						(762)						(233)						(888)						(2,486)
Adjusted EBITDA from unconsolidated affiliates			3						95						187						247						532
Noncash compensation expense			20						34						8						31						93
Other (b)			75						3						228						(9)						297
Segment adjusted EBITDA			$	1,484					$	2,543					$	900					$	1,892					$	6,819
Depreciation and amortization			$	(325)					$	(361)					$	(88)					$	(354)					$	(1,128)
Equity in net earnings from investments			$	—					$	85					$	143					$	211					$	439
Investments in unconsolidated affiliates			$	33					$	484					$	764					$	1,031					$	2,312
Total assets			$	15,856					$	19,797					$	5,041					$	23,181					$	63,875
Capital expenditures			$	492					$	987					$	258					$	216					$	1,953

(a) - Intersegment revenues are primarily from commodity sales, which are based on the contracted selling price that is generally index-based and settled monthly. Intersegment revenues totaled $3.0 billion for the Natural Gas Gathering and Processing segment, $0.3 billion for the Natural Gas Liquids segment and were not material for the Refined Products and Crude and Natural Gas Pipelines segments.

(b) - Included a gain of $227 million for the Natural Gas Pipelines segment related to the sale of three of our wholly owned interstate natural gas pipeline systems to DT Midstream, Inc.

Year Ended December 31, 2024			Total Segments						Other and Eliminations						Total
			(Millions of dollars)
Reconciliations of total segments to consolidated
Liquids commodity sales			$	19,737					$	(3,287)					$	16,450
Residue natural gas sales			1,340						(10)						1,330
Exchange services and natural gas gathering and processing revenue			760						—						760
Transportation and storage revenue			3,043						(23)						3,020
Other revenue			158						(20)						138
Total revenues (a)			$	25,038					$	(3,340)					$	21,698
Cost of sales and fuel (exclusive of depreciation and operating costs)			$	(16,655)					$	3,344					$	(13,311)
Operating costs			$	(2,486)					$	(10)					$	(2,496)
Depreciation and amortization			$	(1,128)					$	(6)					$	(1,134)
Equity in net earnings from investments			$	439					$	—					$	439
Investments in unconsolidated affiliates			$	2,312					$	4					$	2,316
Total assets			$	63,875					$	194					$	64,069
Capital expenditures			$	1,953					$	68					$	2,021

(a) - Substantially all of our revenues are related to contracts with customers.

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Year Ended December 31, 2023			Natural Gas Gathering and Processing						Natural Gas Liquids						Natural Gas Pipelines						Refined Products and Crude						Total Segments
			(Millions of dollars)
Liquids commodity sales			$	2,479					$	13,666					$	—					$	502					$	16,647
Residue natural gas sales			1,398						—						39						—						1,437
Gathering, processing and exchange services revenue			147						549						—						—						696
Transportation and storage revenue			—						204						582						535						1,321
Other revenue			32						10						2						34						78
Total revenues (a)			4,056						14,429						623						1,071						20,179
Cost of sales and fuel (exclusive of depreciation and operating costs)			(2,364)						(11,592)						(28)						(450)						(14,434)
Operating costs			(467)						(666)						(202)						(198)						(1,533)
Adjusted EBITDA from unconsolidated affiliates			1						67						160						36						264
Noncash compensation expense			19						29						8						6						62
Other (b)			(1)						778						(2)						—						775
Segment adjusted EBITDA			$	1,244					$	3,045					$	559					$	465					$	5,313
Depreciation and amortization			$	(272)					$	(334)					$	(67)					$	(92)					$	(765)
Equity in net earnings from investments			$	(2)					$	58					$	118					$	28					$	202
Investments in unconsolidated affiliates			$	24					$	419					$	526					$	903					$	1,872
Total assets			$	7,078					$	14,974					$	2,624					$	19,531					$	44,207
Capital expenditures			$	448					$	818					$	228					$	52					$	1,546

(a) - Intersegment revenues are primarily from commodity sales, which are based on the contracted selling price that is generally index-based and settled monthly. Intersegment revenues for the Natural Gas Gathering and Processing segment totaled $2.4 billion and were not material for the Natural Gas Liquids, Refined Products and Crude and Natural Gas Pipelines segments.

(b) - Included a settlement gain of $779 million for the Natural Gas Liquids segment related to the Medford incident.

Year Ended December 31, 2023			Total Segments						Other and Eliminations						Total
			(Millions of dollars)
Reconciliations of total segments to consolidated
Liquids commodity sales			$	16,647					$	(2,480)					$	14,167
Residue natural gas sales			1,437						—						1,437
Gathering, processing and exchange services revenue			696						—						696
Transportation and storage revenue			1,321						(15)						1,306
Other revenue			78						(7)						71
Total revenues (a)			$	20,179					$	(2,502)					$	17,677
Cost of sales and fuel (exclusive of depreciation and operating costs)			$	(14,434)					$	2,505					$	(11,929)
Operating costs			$	(1,533)					$	(2)					$	(1,535)
Depreciation and amortization			$	(765)					$	(4)					$	(769)
Equity in net earnings from investments			$	202					$	—					$	202
Investments in unconsolidated affiliates			$	1,872					$	2					$	1,874
Total assets			$	44,207					$	59					$	44,266
Capital expenditures			$	1,546					$	49					$	1,595

(a) - Substantially all of our revenues are related to contracts with customers.

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												Years Ended December 31,
																		2025						2024						2023
Reconciliation of income before income taxes to total segment adjusted EBITDA															(Millions of dollars)
Income before income taxes																		$	4,490					$	4,110					$	3,497
Interest expense, net of capitalized interest																		1,783						1,371						866
Depreciation and amortization																		1,514						1,134						769
Adjusted EBITDA from unconsolidated affiliates																		516						532						264
Equity in net earnings from investments																		(386)						(439)						(202)
Noncash compensation expense and other (a)																		103						76						49
Corporate other (b)																		(65)						35						70
Total segment adjusted EBITDA (c)(d)																		$	7,955					$	6,819					$	5,313

(a) - The year ended December 31, 2025, included noncash transaction costs related primarily to the EnLink Acquisition of $16 million included within noncash compensation expense and other.

(b) - The year ended December 31, 2025, included corporate net gains on extinguishment of debt of $106 million in connection with open market repurchases and interest income of $33 million, offset partially by transaction costs related primarily to the EnLink Acquisition of $65 million. The year ended December 31, 2024, included transaction costs related primarily to the EnLink Acquisitions and Medallion Acquisition of $73 million, offset partially by interest income of $39 million. The year ended December 31, 2023, included transaction costs related to the Magellan Acquisition of $158 million, offset partially by interest income of $49 million and corporate net gains on extinguishment of debt of $41 million in connection with open market repurchases.

(c) - The year ended December 31, 2024, included a gain of $227 million from the interstate natural gas pipeline divestiture.

(d) - The year ended December 31, 2023, included $633 million related to the Medford incident, including a settlement gain of $779 million, offset partially by $146 million of third-party fractionation costs.