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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion and analysis should be read in conjunction with Part I, Item 1, Business, our audited Consolidated Financial Statements and the Notes to Consolidated Financial Statements in this Annual Report.

RECENT DEVELOPMENTS

Please refer to the “Financial Results and Operating Information” and “Liquidity and Capital Resources” sections of Management’s Discussion and Analysis of Financial Condition and Results of Operations in this Annual Report for additional information.

Acquisitions

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.

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 of the closing date of the EnLink Acquisition. EnLink is now a wholly owned subsidiary.

For additional information on our most recent acquisitions, see Part II, Item 8, Note B of the Notes to Consolidated Financial Statements in this Annual Report. See Part I, Item 1A “Risk Factors” for further discussion of risks related to these transactions.

Joint Ventures

Eiger Express Pipeline - 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. We expect to invest a total of approximately $350 million into this project, which is expected to be completed in mid-2028.

Texas City Logistics and MBTC Pipeline - In February 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. MBTC Pipeline, the pipeline joint venture, is owned 80% by us and 20% by MPLX LP, and we will construct and operate the pipeline. We expect to invest a total of approximately $1.0 billion into these projects, which are expected to be completed in early 2028.

Market Conditions - Earnings increased in 2025, compared with 2024, due primarily to a full year of earnings from EnLink and Medallion across our segments and higher NGL and natural gas processing volumes. Our extensive and integrated assets are located in, and connected with, some of the most productive shale basins, as well as refineries and demand centers, in the United States.

One Big Beautiful Bill Act (OBBBA) - On July 4, 2025, the OBBBA was signed into law. The OBBBA makes changes to U.S. tax law and includes provisions that, beginning in January 2025, make permanent full expensing of tangible personal property and restore EBITDA-based calculations for purposes of the business interest deduction. We expect the OBBBA to reduce our cash taxes beginning with the 2025 tax year; however, we do not anticipate the OBBBA to materially impact net income.

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Capital Projects - Our primary capital projects are outlined in the table below:

Project Scope ApproximateCost (a) Expected Completion

Natural Gas Gathering and Processing (In millions)

Natural Gas Liquids

Natural Gas Pipelines

Refined Products and Crude

(a) - Excludes capitalized interest/AFUDC. For our Texas City Logistics, MBTC Pipeline and Eiger joint venture projects, the amounts presented exclude capital contributions from the other joint venture members.

(b) - This project is expected to be completed in two phases, with the first phase expected to be completed in the fourth quarter of 2026, and the second phase completed in the first quarter of 2027.

(c) - Our investments in Texas City Logistics and Eiger are accounted for using the equity method. Spending on these projects will be recorded as contributions to unconsolidated affiliates.

In our Natural Gas Gathering and Processing segment, we are relocating a 150 MMcf/d processing plant to the Permian Basin from North Texas, which we expect to be completed in the first quarter of 2026.

For a discussion of our capital expenditures financing, see “Capital Expenditures” in the Liquidity and Capital Resources” section.

Debt Issuances - In August 2025, we completed an underwritten public offering of $3.0 billion senior unsecured notes consisting of $750 million, 4.95% senior notes due 2032; $1.0 billion, 5.4% senior notes due 2035; and $1.25 billion, 6.25% senior notes due 2055. 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 offerings were used for general corporate purposes, including the repurchase and redemption of existing notes.

Debt Extinguishments - We completed the following debt extinguishments in 2025:

Principal

(Millions of dollars)

Open Market Repurchases (b) 789

(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.

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Share Repurchase Program - Our Board of Directors authorized a share repurchase program to buy up to $2.0 billion of our outstanding common stock. 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 with cash on hand.

Dividends - During 2025, we paid common stock dividends totaling $4.12 per share, an increase of 4% compared to the 2024 dividend of $3.96 per share. In February 2026, we paid a quarterly common stock dividend of $1.07 per share ($4.28 per share on an annualized basis). Our dividend growth is due primarily to the increase in cash flows resulting from the growth of our operations. The quarterly stock dividend was paid on February 13, 2026, to shareholders of record at the close of business on February 2, 2026.

FINANCIAL RESULTS AND OPERATING INFORMATION

How We Evaluate Our Operations

Management uses a variety of financial and operating metrics to analyze our performance. Our consolidated financial metrics include: (1) operating income; (2) net income; (3) diluted EPS; and (4) adjusted EBITDA. We evaluate segment operating results using adjusted EBITDA and our operating metrics, which include various volume and rate statistics that are relevant for the respective segment. These operating metrics allow investors to analyze the various components of segment financial results in terms of volumes and rate/price. Management uses these metrics to analyze historical segment financial results and as the key inputs for forecasting and budgeting segment financial results. For additional information on our operating metrics, see the respective segment subsections of this “Financial Results and Operating Information” section.

Non-GAAP Financial Measures - Adjusted EBITDA is a non-GAAP measure of our financial performance. Adjusted EBITDA 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. Our calculation includes adjusted EBITDA related to our unconsolidated affiliates using the same recognition and measurement methods used to record equity in net earnings from investments. 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.

We believe this non-GAAP financial measure is useful to investors because it and similar measures are used by many companies in our industry as a measurement of financial performance and is commonly employed by financial analysts and others to evaluate our financial performance and to compare financial performance among companies in our industry. Adjusted EBITDA should not be considered an alternative to net income, EPS or any other measure of financial performance presented in accordance with GAAP. Additionally, this calculation may not be comparable with similarly titled measures of other companies. See reconciliation of net income to adjusted EBITDA in the “Non-GAAP Financial Measures” subsection.

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Consolidated Operations

Selected Financial Results - The following table sets forth certain selected financial results for the periods indicated:

(Millions of dollars, except per share amounts)

Revenues

Changes in commodity prices and sales volumes affect both revenues and cost of sales and fuel and, therefore, the impact is largely offset between these line items.

Due to the Medallion Acquisition and EnLink Controlling Interest Acquisition, operating results for these two companies are included in our financial results beginning November 1, 2024, and October 15, 2024, respectively.

2025 vs. 2024 - Operating income increased $752 million primarily as a result of the following:

•Natural Gas Gathering and Processing - an increase of $469 million due primarily to the operating income of EnLink and higher volumes in the Mid-Continent and Rocky Mountain regions, offset partially by lower realized NGL prices, net of hedging, and the impact from the divestiture of certain nonstrategic assets in 2024; and

•Natural Gas Liquids - an increase of $120 million due primarily to the operating income of EnLink, higher exchange services and higher optimization and marketing, offset partially by higher operating costs; offset by

•Natural Gas Pipelines - adecrease of $104 million due primarily to the impact of the interstate natural gas pipeline divestiture in 2024, offset partially by the operating income of EnLink and higher optimization and marketing; offset by

•Refined Products and Crude - an increase of $276 million due primarily to the operating income of Medallion and EnLink and lower operating costs.

Net income and diluted EPS increased due primarily to the items discussed above, offset partially by higher interest expense due to higher debt balances resulting from the September 2024 $7.0 billion notes offering, the August 2025 $3.0 billion notes offering, the acquired debt balances from the EnLink Controlling Interest Acquisition in 2024 and increased short-term borrowings in 2025 and higher equity in net earnings from investments in 2024.

Capital expenditures increased due primarily to the timing of our large capital projects and routine capital projects associated with the growth of our operations. Please refer to the “Recent Developments” section of Management’s Discussion and Analysis of Financial Condition and Results of Operations in this Annual Report for additional information on our capital projects.

Additional information regarding our financial results and operating information is provided in the following discussion for each of our segments.

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Selected Financial Results and Operating Information for the Year Ended December 31, 2024 vs. 2023 - The consolidated and segment financial results and operating information for the year ended December 31, 2024, compared with the year ended December 31, 2023, are included in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations of our 2024 Annual Report on Form 10-K, which is available via the SEC’s website at www.sec.gov and our website at www.oneok.com.

Natural Gas Gathering and Processing

Capital Projects - Our Natural Gas Gathering and Processing segment invests in capital projects in natural gas and NGL-rich areas across key basins where we operate. Our growth strategy is focused on providing solutions to producer customers that expand our presence within our key operating regions. See “Capital Projects” in the “Recent Developments” section for more information on our capital projects.

For a discussion of our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.

Selected Financial Results and Operating Information - The following tables set forth certain selected financial results and operating information for our Natural Gas Gathering and Processing segment for the periods indicated:

(Millions of dollars)

Adjusted EBITDA from unconsolidated affiliates 5 3 1 2 2

Changes in commodity prices and sales volumes affect both revenue and cost of sales and fuel and, therefore, the impact is largely offset between these line items.

2025 vs. 2024 - Adjusted EBITDA increased $654 million primarily as a result of the following:

•an increase of $740 million due to adjusted EBITDA from EnLink; and

•an increase of $99 million from higher volumes due primarily to increased production in the Mid-Continent and Rocky Mountain regions; offset by

•a decrease of $122 million due to lower realized prices, primarily NGL prices, net of hedging; and

•a decrease of $81 million from the divestiture of certain nonstrategic assets in 2024.

Capital expenditures increased in 2025 due primarily to our routine and large capital projects, including our projects to relocate a processing plant to the Permian Basin from North Texas and construct our Bighorn processing plant in the Permian Basin.

Years Ended December 31,

(a) - Included volumes for consolidated entities only and excluded EnLink operating statistics for 2024 as they were not meaningful to full-year 2024 operating results.

(b) - Included volumes we processed at company-owned and third-party facilities.

2025 vs. 2024 - Our natural gas processed volumes increased in 2025 due to incremental volumes from EnLink and increased production in the Mid-Continent and Rocky Mountain regions.

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Natural Gas Liquids

Capital Projects - Our Natural Gas Liquids segment invests in capital projects to transport, fractionate, store, deliver to market centers and receive NGL supply from shale and other resource development areas. Our growth strategy is focused on connecting diversified raw feed supply basins to Purity NGL export, petrochemical and refining demand centers. See “Capital Projects” in the “Recent Developments” section for more information on our capital projects.

For a discussion of our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.

Selected Financial Results and Operating Information - The following tables set forth certain selected financial results and operating information for our Natural Gas Liquids segment for the periods indicated:

(Millions of dollars)

Adjusted EBITDA from unconsolidated affiliates 101 95 67 6 28

Changes in commodity prices and sales volumes affect both revenues and cost of sales and fuel and, therefore, the impact is largely offset between these line items.

2025 vs. 2024 - Adjusted EBITDA increased $236 million primarily as a result of the following:

•an increase of $183 million due to adjusted EBITDA from EnLink;

•an increase of $39 million in exchange services due primarily to:

◦$94 million of higher volumes in the Rocky Mountain region; and

◦$27 million of higher average fee rates in the Rocky Mountain region; offset partially by

◦$44 million of lower average fee rates in the Mid-Continent region;

◦$21 million of lower volumes in the Mid-Continent region; and

◦$20 million of higher transportation costs and higher inventory of unfractionated NGLs; and

•an increase of $31 million in optimization and marketing due primarily to higher earnings on sales of Purity NGLs held in inventory; offset by

•an increase of $16 million in operating costs due primarily to higher employee-related costs associated with the growth of our operations.

Capital expenditures decreased in 2025 due primarily to the completion of our MB-6 fractionator and pipeline expansion projects in 2024, offset partially by our Medford fractionator rebuild project.

Years Ended December 31,

(a) - Represents physical raw feed volumes for which we provided transportation and/or fractionation services, and excluded EnLink operating statistics in 2024 as they were not meaningful to full-year 2024 operating results.

We generally expect ethane volumes to increase or decrease with corresponding increases or decreases in overall NGL production. However, ethane volumes may experience growth or decline greater than corresponding growth or decline in overall NGL production due to ethane economics causing producers to recover or reject ethane.

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2025 vs. 2024 - Volumes increased in 2025 due primarily to incremental volumes from EnLink, higher ethane volumes in the Rocky Mountain region and higher volumes on short-term fractionation contracts in the Gulf Coast region, offset partially by lower ethane volumes in the Mid-Continent region.

Natural Gas Pipelines

Capital Projects - Our Natural Gas Pipelines segment invests in capital projects that provide transportation and services to end users. Our growth strategy is focused on expanding our transportation and storage capacity and services by connecting residue natural gas supply to demand markets and end users. See “Capital Projects” in the “Recent Developments” section for more information on our capital projects.

For a discussion of our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.

Interstate Natural Gas Pipeline Divestiture - On December 31, 2024, we completed the sale of three of our wholly owned interstate natural gas pipeline systems to DT Midstream, Inc.

Selected Financial Results and Operating Information - The following tables set forth certain selected financial results and operating information for our Natural Gas Pipelines segment for the periods indicated:

(Millions of dollars)

Changes in commodity prices and sales volumes affect both revenues and cost of sales and fuel and, therefore, the impact is largely offset between these line items.

2025 vs. 2024 - Adjusted EBITDA decreased $39 million primarily as a result of the following:

•a decrease of $359 million due to the interstate natural gas pipeline divestiture in 2024, offset by

•an increase of $253 million due to adjusted EBITDA from EnLink;

•an increase of $33 million due to optimization and marketing activity;

•an increase of $14 million in storage services due primarily to increased storage volumes; and

•an increase of $12 million in transportation services due primarily to higher transportation rates and volumes.

Capital expenditures decreased in 2025 due primarily to the completion of capital projects in 2024, offset partially by increased growth projects primarily from EnLink.

Years Ended December 31,

Natural gas transportation capacity contracted (MDth/d) 7,315 8,176 7,743

Transportation capacity contracted 91 % 97 % 96 %

(a) - Included volumes for consolidated entities only and excluded EnLink operating statistics in 2024 as they were not meaningful to full-year 2024 operating results.

2025 vs. 2024 - Natural gas transportation capacity decreased due primarily to the interstate natural gas pipeline divestiture in 2024, offset partially by EnLink transportation capacity contracted included in 2025.

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Refined Products and Crude

Capital Projects - Our Refined Products and Crude segment invests in capital projects to transport, store and distribute Refined Products and crude oil primarily throughout the central United States. Our growth strategy is focused on expanding our core business and marketing presence. See “Capital Projects” in the “Recent Developments” section for more information on our capital projects.

For a discussion of our capital expenditure financing, see “Capital Expenditures” in the “Liquidity and Capital Resources” section.

Selected Financial Results and Operating Information - The following tables set forth certain selected financial results and operating information for our Refined Products and Crude segment for the periods indicated:

Years Ended December 31, September 25 through December 31, 2025 vs. 2024

(Millions of dollars)

Operating costs, excluding noncash compensation adjustments (879) (857) (192) 22

Adjusted EBITDA from unconsolidated affiliates 166 247 36 (81)

(a) - The year ended December 31, 2023, included results subsequent to the Magellan Acquisition.

Changes in commodity prices and sales volumes affect both revenues and cost of sales and fuel and, therefore, the impact is largely offset between these line items.

2025 vs. 2024 - Adjusted EBITDA increased $285 million primarily as a result of the following:

•an increase of $295 million due to adjusted EBITDA from Medallion and EnLink;

•a decrease of $55 million in operating costs due primarily to $40 million of lower outside services and $13 million of lower property taxes; and

•an increase of $28 million due primarily to the sale of environmental credits generated by our liquids blending business; offset by

•a decrease of $81 million in adjusted EBITDA from unconsolidated affiliates due primarily to lower earnings on BridgeTex associated with the nonrecurring recognition of deferred revenue in 2024; and

•a decrease of $10 million in optimization and marketing due primarily to lower liquids blending margins.

Capital expenditures increased in 2025, due primarily to our routine and large capital projects, including our greater Denver Refined Products pipeline expansion project.

Years Ended Three Months Ended

December 31, December 31,

(a) - Included volumes for consolidated entities only and excluded Medallion and EnLink operating statistics in 2024 as they were not

meaningful to full-year 2024 operating results.

2025 vs. 2024 - Refined Products volumes shipped remained relatively unchanged.

Crude oil volumes shipped increased in 2025 due primarily to incremental volumes from Medallion and EnLink.

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Non-GAAP Financial Measures

The following table sets forth a reconciliation of net income, the nearest comparable GAAP financial performance measure, to adjusted EBITDA for the periods indicated:

Years Ended December 31,

Reconciliation of net income to adjusted EBITDA (Millions of dollars)

Interest expense, net of capitalized interest 1,783 1,371 866

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

Reconciliation of segment adjusted EBITDA to adjusted EBITDA

Segment adjusted EBITDA:

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

(e) - The year ended December 31, 2023, included segment adjusted EBITDA for the period September 25, 2023, through December 31, 2023.

CONTINGENCIES

See Note O of the Notes to Consolidated Financial Statements in this Annual Report for a discussion of regulatory and legal matters.

Other 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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LIQUIDITY AND CAPITAL RESOURCES

General - Our primary sources of cash inflows are operating cash flows, proceeds from our commercial paper program and our $3.5 Billion Credit Agreement, debt issuances and the issuance of common stock for our liquidity and capital resource requirements.

We expect our sources of cash inflows to provide sufficient resources to finance our operations, capital expenditures, quarterly cash dividends, maturities of long-term debt, share repurchases and contributions to unconsolidated affiliates and joint ventures. We believe we have sufficient liquidity due to our $3.5 Billion Credit Agreement, which expires in February 2030, our $3.5 billion commercial paper program and access to $1.0 billion available through our “at-the-market” equity program. As of February 16, 2026, no shares have been sold through our “at-the-market” equity program.

We may manage interest-rate risk through the use of fixed-rate debt, floating-rate debt, Treasury locks and interest-rate swaps. For additional information on our interest-rate derivative instruments, see Note D of the Notes to Consolidated Financial Statements in this Annual Report.

Cash Management - At December 31, 2025, we had $78 million of cash and cash equivalents. For our wholly owned subsidiaries, we use a centralized cash management program that concentrates the cash assets of our wholly owned nonguarantor operating subsidiaries in joint accounts for the purposes of providing financial flexibility and lowering the cost of borrowing, transaction costs and bank fees. Our centralized cash management program provides that funds in excess of the daily needs of our operating subsidiaries are concentrated, consolidated or otherwise made available for use by other entities within our consolidated group. Our operating subsidiaries participate in this program to the extent they are permitted pursuant to FERC regulations or their operating agreements. Under the cash management program, depending on whether a participating subsidiary has short-term cash surpluses or cash requirements, we provide cash to the subsidiary or the subsidiary provides cash to us.

Following the completion of the EnLink Acquisition on January 31, 2025, we terminated an agreement to provide revolving unsecured loans to EnLink through a promissory note, as EnLink operating subsidiaries are wholly owned and now participate in the cash management program described above. For additional information, see Note G of the Notes to Consolidated Financial Statements in this Annual Report.

Guarantees - ONEOK, ONEOK Partners, the Intermediate Partnership, Magellan, EnLink and EnLink Partners have cross guarantees in place for ONEOK’s and ONEOK Partners’ indebtedness. These guarantees in place for our and ONEOK Partners’ indebtedness are full, irrevocable, unconditional and absolute joint and several guarantees to the holders of each series of outstanding securities. Liabilities under the guarantees rank equally in right of payment with all of the guarantors’ existing and future senior unsecured indebtedness. The Intermediate Partnership holds all of ONEOK Partners’ interests and equity in its subsidiaries, which are nonguarantors, and substantially all the assets and operations reside with nonguarantor operating subsidiaries. Magellan, EnLink and EnLink Partners hold interests in their subsidiaries, which are nonguarantors, and substantially all the assets and operations reside with nonguarantor operating subsidiaries. Therefore, as allowed under Rule 13-01 of Regulation S-X, we have excluded the summarized financial information for each issuer and guarantor as the combined financial information of subsidiary issuers and parent guarantors, excluding our ownership of all interest in ONEOK Partners, Magellan and EnLink, reflect no material assets or liabilities or results of operations apart from guaranteed indebtedness.

For additional information on our indebtedness, see Note G of the Notes to Consolidated Financial Statements in this Annual Report.

Short-term Liquidity - Our principal sources of short-term liquidity consist of cash generated from operating activities, distributions received from our unconsolidated affiliates, proceeds from our commercial paper program and our $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. All other terms and conditions remain substantially the same. In September 2025, we increased the size of our commercial paper program to $3.5 billion from $2.5 billion. As of February 16, 2026, we had no borrowings under our $3.5 Billion Credit Agreement, and we are in compliance with all covenants. Upon closing of the EnLink Acquisition on January 31, 2025, the EnLink Revolving Credit Facility was terminated. For additional information on the EnLink Revolving Credit Facility, see Note G of the Notes to Consolidated Financial Statements in this Annual Report.

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We had working capital (defined as current assets less current liabilities) deficits of $1.9 billion and $481 million as of December 31, 2025, and December 31, 2024, respectively, due primarily to current maturities of long-term debt and short-term borrowings at December 31, 2025, and current maturities of long-term debt at December 31, 2024. Generally, our working capital is influenced by several factors, including, among other things: (i) the timing of (a) debt and equity issuances, (b) the funding of capital expenditures, (c) scheduled debt payments, and (d) accounts receivable and payable; and (ii) the volume and cost of inventory and commodity imbalances. We may have working capital deficits in future periods as our long-term debt becomes current. We do not expect a working capital deficit of this nature to have a material adverse impact to our cash flows or operations.

For additional information on our $3.5 Billion Credit Agreement, see Note G of the Notes to Consolidated Financial Statements in this Annual Report.

Long-term Financing - In addition to our principal sources of short-term liquidity discussed above, we expect to fund our longer-term financing requirements by issuing long-term notes, as needed. Other options to obtain financing include, but are not limited to, issuing common stock, loans from financial institutions, issuance of convertible debt securities or preferred equity securities, asset securitization and the sale and lease-back of facilities.

We may, at any time, seek to retire or purchase our or ONEOK Partners’ outstanding debt through cash purchases and/or exchanges for equity or debt, in open market repurchases, privately negotiated transactions, exercise of contractual call rights, public tender offers or otherwise. Such repurchases and exchanges, if any, will be on such terms and prices as we may determine and will depend on prevailing market conditions, or liquidity requirements, contractual restrictions and other factors. The amounts involved may be material.

Debt Issuances - In August 2025, we completed an underwritten public offering of $3.0 billion senior unsecured notes consisting of $750 million, 4.95% senior notes due 2032; $1.0 billion, 5.4% senior notes due 2035; and $1.25 billion, 6.25% senior notes due 2055. 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.

Debt Extinguishments - We completed the following debt extinguishments in 2025:

Principal

(Millions of dollars)

Open Market Repurchases (b) 789

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

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.

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Material Commitments - We have material cash commitments related to our capital expenditures, senior notes and corresponding interest payments, which we expect to fund through our sources of cash inflows discussed above. Our senior notes and interest payments are discussed in Note G of the Notes to Consolidated Financial Statements in this Annual Report. We also have cash commitments related to transportation, storage and other commercial contracts, as well as our financial and physical derivative obligations, which we expect to fund with cash from operations.

Capital Expenditures- We proactively monitor lead times on materials and equipment used in constructing capital projects, and we enter into procurement agreements for long-lead items for potential projects to plan for future growth. Our capital expenditures are financed typically through operating cash flows and short- and long-term debt.

The following table sets forth our capital expenditures, less allowance for equity funds used during construction, for the periods indicated:

(Millions of dollars)

Natural Gas Gathering and Processing $ 1,314 $ 492 $ 448

Refined Products and Crude (b) 752 216 52

(a) - The year ended December 31, 2024, included capital expenditures for EnLink and Medallion for the period October 15, 2024, and November 1, 2024, through December 31, 2024, respectively.

(b) - The year ended December 31, 2023, included capital expenditures for Magellan for the period September 25, 2023, through December 31, 2023.

Capital expenditures increased in 2025, compared with 2024, due primarily to the timing of our large capital projects and routine capital projects associated with the growth of our operations. See discussion of our announced capital projects in the “Recent Developments” section.

We expect total capital expenditures of $2.7 - $3.2 billion in 2026.

Credit Ratings - Our credit ratings as of February 16, 2026, are shown in the table below:

Rating Agency Long-term Rating Short-term Rating Outlook

Moody’s Baa2 Prime-2 Stable

S&P BBB A-2 Stable

Fitch BBB F2 Stable

Our credit ratings, which are investment grade, may be affected by our leverage, liquidity, credit profile or potential transactions. The most common criteria for assessment of our credit ratings are the debt-to-EBITDA ratio, interest coverage, business risk profile and liquidity. If our credit ratings were downgraded, our cost to borrow funds under our $3.5 Billion Credit Agreement could increase, and a potential loss of access to the commercial paper market could occur. In the event that we are unable to borrow funds under our commercial paper program and there has not been a material adverse change in our business, we would continue to have access to our $3.5 Billion Credit Agreement, which expires in 2030. An adverse credit rating change alone is not a default under our $3.5 Billion Credit Agreement.

In the normal course of business, our counterparties provide us with secured and unsecured credit. In the event of a downgrade in our credit ratings or a significant change in our counterparties’ evaluation of our creditworthiness, we could be required to provide additional collateral in the form of cash, letters of credit or other negotiable instruments as a condition of continuing to conduct business with such counterparties. We may be required to fund margin requirements with our counterparties with cash, letters of credit or other negotiable instruments.

Dividends - Holders of our common stock share equally in any common stock dividends declared by our Board of Directors. In 2025, we paid common stock dividends totaling $4.12 per share, an increase of 4% compared to the 2024 dividend of $3.96 per share. In February 2026, we paid a quarterly common stock dividend of $1.07 per share ($4.28 per share on an annualized basis), an increase of 4% compared with the same quarter in the prior year.

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For the year ended December 31, 2025, our cash flows from operations exceeded dividends paid by $3.0 billion. We expect our cash flows from operations to continue to sufficiently fund our cash dividends. To the extent operating cash flows are not sufficient to fund our dividends, we may utilize cash on hand from other sources of short- and long-term liquidity to fund a portion of our dividends.

CASH FLOW ANALYSIS

We use the indirect method to prepare our Consolidated Statements of Cash Flows. Under this method, we reconcile net income to cash flows provided by operating activities by adjusting net income for those items that affect net income but do not result in actual cash receipts or payments during the period and for operating cash items that do not impact net income. These reconciling items can include depreciation and amortization, deferred income taxes, impairment charges, allowance for equity funds used during construction, gain or loss on sale of business and assets, net undistributed earnings from unconsolidated affiliates, share-based compensation expense, other amounts and changes in our assets and liabilities not classified as investing or financing activities.

The following table sets forth the changes in cash flows by operating, investing and financing activities for the periods indicated:

Years Ended December 31,

(Millions of dollars)

Total cash provided by (used in):

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

Operating Cash Flows - Operating cash flows are affected by earnings from our business activities and changes in our operating assets and liabilities. Changes in commodity prices and demand for our services or products, whether because of general economic conditions, changes in supply, changes in demand for the end products that are made with our products or increased competition from other service providers, could affect our earnings and operating cash flows. Our operating cash flows can also be impacted by changes in our inventory balances, which are driven primarily by commodity prices, supply, demand and the operation of our assets.

2025 vs. 2024 - Cash flows from operating activities, before changes in operating assets and liabilities increased $1.0 billion for the year ended December 31, 2025, compared with the same period in 2024, due primarily to the impact of the EnLink and Medallion Acquisitions as discussed in “Financial Results and Operating Information.”

The changes in operating assets and liabilities decreased operating cash flows $380 million for the year ended December 31, 2025, compared with a decrease of $43 million for the same period in 2024. This change is due primarily to changes in accounts receivable resulting from the growth of our operations and the timing of the receipt of cash from counterparties and from inventory, both of which vary from period to period, and with changes in commodity prices. These changes were offset partially by changes in accounts payable resulting from the growth of our operations and the timing of payments to vendors, suppliers and other third parties, which vary from period to period, and with changes in commodity prices.

Investing Cash Flows

2025 vs. 2024 - Cash used in investing activities for the year ended December 31, 2025, decreased $2.9 billion compared with the same period in 2024, due primarily to cash paid to acquire EnLink and Medallion in 2024, offset partially by proceeds received from the interstate natural gas pipeline divestiture in 2024, an increase in capital expenditures related to our capital projects in 2025 and cash paid for the BridgeTex Additional Interest Acquisition.

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Financing Cash Flows

2025 vs. 2024 - Cash from financing activities for the year ended December 31, 2025, decreased $4.6 billion compared with the same period in 2024, due primarily to the issuance of senior unsecured notes associated with acquisitions in 2024, increased extinguishment of long-term debt in 2025, cash paid for the Delaware Basin JV Acquisition and increased dividends paid in 2025, offset partially by the issuance of senior unsecured notes in August 2025 and an increase in short-term borrowings in 2025.

Cash Flow Analysis for the Year Ended December 31, 2024 vs. 2023 - The cash flow analysis for the year ended December 31, 2024, compared with the year ended December 31, 2023, is included in Part II, Item 7, Management’s Discussion and Analysis of Financial Condition and Results of Operations of our 2024 Annual Report on Form 10-K, which is available via the SEC’s website at www.sec.gov and our website at www.oneok.com.

IMPACT OF NEW ACCOUNTING STANDARDS

Information about the impact of new accounting standards is included in Note Aof the Notes to Consolidated Financial Statements in this Annual Report.

CRITICAL ACCOUNTING 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 of assets and liabilities, and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements. These estimates and assumptions also affect the reported amounts of revenue and expenses during the reporting period. Although we believe these estimates and assumptions are reasonable, actual results could differ from our estimates.

The following is a summary of our most critical accounting estimates, which are defined as those estimates most important to the portrayal of our financial condition and results of operations and requiring management’s most difficult, subjective or complex judgment, particularly because of the need to make estimates concerning the impact of inherently uncertain matters. We have discussed the development and selection of our critical accounting estimates with the Audit Committee of our Board of Directors. See Note A of the Notes to Consolidated Financial Statements in this Annual Report for the description of our accounting policies.

Derivatives and Risk-management Activities - We utilize derivatives to reduce our market-risk exposure to commodity price and interest-rate fluctuations and to achieve more predictable cash flows. The accounting for changes in the fair value of a derivative instrument depends on whether it qualifies and has been designated as part of a hedging relationship. When possible, we implement effective hedging strategies using derivative financial instruments that qualify as hedges for accounting purposes. We have not used derivative instruments for trading purposes. For a derivative designated as a cash flow hedge, the gain or loss from a change in fair value of the derivative instrument is deferred in accumulated other comprehensive loss until the forecasted transaction affects earnings, at which time the fair value of the derivative instrument is reclassified into earnings.

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 do not believe that changes in our fair value estimates of our derivative instruments have a material impact on our results of operations, as the majority of our derivatives are accounted for as effective cash flow hedges. However, if a derivative instrument is ineligible for cash flow hedge accounting or if we elect not to designate it as a cash flow hedge, changes in fair value of the derivative instrument would be recorded currently in earnings. Additionally, if a cash flow hedge ceases to qualify for hedge accounting treatment because it is no longer probable that the forecasted transaction will occur, the change in fair value of the derivative instrument would be recognized in earnings. For more information on commodity price sensitivity and a discussion of the market risk of pricing changes, see Item 7A, Quantitative and Qualitative Disclosures about Market Risk.

See Notes A, C and D of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of fair value measurements and derivatives and risk-management activities.

Impairment of Goodwill, 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. As part of our goodwill impairment test, we may first assess qualitative factors (including macroeconomic conditions, industry and market considerations, cost factors and overall financial performance) to determine

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whether it is more likely than not that the fair value of each of our reporting units was less than its carrying amount. If further testing is necessary, or a quantitative test is elected, we perform a Step 1 analysis for goodwill impairment.

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.

We assess our long-lived asset groups, including intangible assets, 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.

We evaluate equity method investments in unconsolidated affiliates for impairment whenever events or circumstances indicate that there is an other-than-temporary loss in value of the investment. When evidence of loss in value has occurred, we compare our estimate of fair value of the investment to the carrying value of the investment to determine whether an impairment has occurred. If the estimated fair value is less than the carrying value and we consider the decline in value to be other-than-temporary, the excess of the carrying value over the fair value is recognized in our consolidated financial statements as an impairment charge.

Our impairment tests require the use of assumptions and estimates, such as industry economic factors and the profitability of future business strategies. To estimate undiscounted future cash flows of long-lived assets we may apply a probability-weighted approach that incorporates different assumptions and potential outcomes related to the underlying long-lived assets. The evaluation is performed at the lowest level for which separately identifiable cash flows exist. To estimate the fair value of these assets, we use two generally accepted valuation approaches, an income approach and a market approach. Under the income approach, our discounted cash flow analysis includes the following inputs that are not readily available: a discount rate reflective of industry cost of capital, our estimated contract rates, volumes, operating margins, operating and maintenance costs and capital expenditures. Under the market approach, our inputs include EBITDA multiples, which are estimated from recent peer acquisition transactions, and forecasted EBITDA, which incorporates inputs similar to those used under the income approach. If actual results are not consistent with our assumptions and estimates or our assumptions and estimates change due to new information, we may be exposed to future impairment charges.

See Notes A, E, F and N of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of goodwill and intangible assets, long-lived assets and investments in unconsolidated affiliates.

Depreciation Methods and Estimated Useful Lives of Property, Plant and Equipment - Our property, plant and equipment are depreciated using the straight-line method that incorporates management assumptions regarding useful economic lives and residual values. As we place additional assets in service or acquire assets as a result of an acquisition or asset purchase, our estimates related to depreciation expense have become more significant and changes in estimated useful lives of our assets could have a material effect on our results of operations. At the time we place our assets in service, we believe such assumptions are reasonable; however, circumstances may develop that would cause us to change these assumptions, which would change our depreciation expense prospectively. Examples of such circumstances include changes in (i) competition, (ii) laws and regulations that limit the estimated economic life of an asset, (iii) technology that render an asset obsolete, (iv) expected salvage values, (v) results of rate cases or rate settlements on regulated assets and (vi) forecasts of the remaining economic life for the resource basins where our assets are located, if any. For the fiscal years presented in this Form 10-K, no changes were made to the determinations of useful lives that would have a material effect on the timing of depreciation expense in future periods.

See Note E of the Notes to Consolidated Financial Statements in this Annual Report for additional discussion of property, plant and equipment.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Our exposure to market risk, discussed below, includes forward-looking statements and represents an estimate of possible changes in future earnings that could occur assuming hypothetical future movements in interest rates or commodity prices within our derivative portfolio. Our views on market risk are not necessarily indicative of actual results that may occur and do not represent the maximum possible gains and losses that may occur since actual gains and losses will differ from those estimated based on actual fluctuations in interest rates or commodity prices and the timing of transactions.

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We are exposed to market risk due to commodity price and interest-rate volatility. Market risk is the risk of loss arising from adverse changes in market rates and prices. We may use financial instruments, including forward sales, swaps, options and futures, to manage the risks of certain identifiable or anticipated transactions and achieve more predictable cash flows. Our risk-management function follows policies and procedures established by our Risk Oversight and Strategy Committee to monitor our natural gas, NGL, Refined Products, condensate and crude oil marketing activities and interest rates to ensure our hedging activities mitigate market risks and comply with approved thresholds or limits. We do not use financial instruments for trading purposes.

We utilize a sensitivity analysis model to assess the risk associated with our derivative portfolio. The sensitivity analysis measures the potential change in fair value of our derivative instruments based upon a hypothetical 10% movement in the underlying commodity prices or interest rates. In addition to these variables, the fair value of our derivative portfolio is influenced by fluctuations in the notional amounts of the instruments and the discount rates used to determine the present values. Because we enter into these derivative instruments for the purpose of mitigating the risks that accompany certain of our business activities, as described below, the change in the market value of our derivative portfolio would typically be offset largely by a corresponding gain or loss on the hedged item.

See Note Aof the Notes to Consolidated Financial Statements in this Annual Report for a discussion on our accounting policies for our derivative instruments and the impact on our Consolidated Financial Statements.

COMMODITY PRICE RISK

As part of our hedging strategy, we use commodity derivative financial instruments and physical-forward contracts described in Note D of the Notes to Consolidated Financial Statements in this Annual Report to reduce the impact of near-term price fluctuations of natural gas, NGLs, Refined Products, condensate and crude oil.

The following table presents the effect a hypothetical 10% change in the underlying commodity prices would have on the estimated fair value of our commodity derivative instruments as of the dates indicated:

December 31,

(Millions of dollars)

Refined Products, crude oil and NGLs $ 80 $ 61

Natural gas 9 9

Total change in estimated fair value of commodity contracts $ 89 $ 70

Our sensitivity analysis represents an estimate of the reasonably possible gains and losses that would be recognized on our commodity derivative contracts assuming hypothetical movements in future market prices and is not necessarily indicative of actual results that may occur. Actual gains and losses may differ from estimates due to actual fluctuations in market prices, as well as changes in our commodity derivative portfolio during the year.

INTEREST-RATE RISK

We are exposed to interest-rate risk through borrowings under our $3.5 Billion Credit Agreement, commercial paper program and long-term debt issuances. Future increases in commercial paper rates or bond yields could expose us to increased interest costs on future borrowings. 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.

See Note D of the Notes to Consolidated Financial Statements in this Annual Report for more information on our hedging activities.

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COUNTERPARTY CREDIT RISK

We assess the creditworthiness of our counterparties on an ongoing basis and require security, including prepayments, letters of credit, liens and other forms of collateral, when appropriate. Certain of our counterparties may be impacted by a relatively low commodity price environment and could experience financial problems, which could result in nonpayment and/or nonperformance, which could adversely impact our results of operations. Following our acquisitions in 2024, we now transact with the counterparties of EnLink and Medallion. A substantial portion of EnLink and Medallion counterparties are rated investment-grade by S&P or provide a letter of credit or other collateral.

Natural Gas Gathering and Processing - Our Natural Gas Gathering and Processing segment derives fees for services primarily from major and independent crude oil and natural gas producers, which include both large integrated and independent exploration and production companies. In this segment, our downstream commodity sales customers are primarily utilities, large industrial companies, marketing companies and our NGL affiliate. We are not typically exposed to material credit risk with producers under fee with POP contracts as we sell the commodities and remit a portion of the sales proceeds back to the producer less our contractual fees. In 2025 and 2024, excluding EnLink in 2024, approximately 75% and 85%, respectively, of the downstream commodity sales in our Natural Gas Gathering and Processing segment were made to customers rated investment-grade by S&P, approved through comparable internal counterparty analysis or were secured by letters of credit or other collateral.

Natural Gas Liquids - Our Natural Gas Liquids segment’s counterparties are primarily NGL and natural gas gathering and processing companies; major and independent crude oil and natural gas production companies; utilities; large industrial companies; natural gasoline distributors; propane distributors; municipalities; and petrochemical, refining and marketing companies. We charge fees to NGL and natural gas gathering and processing counterparties and NGL pipeline transportation customers. We are not typically exposed to material credit risk on the majority of our exchange services fees, as we purchase NGLs from our gathering and processing counterparties and deduct our fee from the amounts we remit. We also earn sales revenue on the downstream sales of Purity NGLs. In 2025 and 2024, excluding EnLink in 2024, approximately 95% and 90%, respectively, of this segment’s commodity sales were made to customers rated investment-grade by S&P, approved through comparable internal counterparty analysis or were secured by letters of credit or other collateral. In addition, the majority of our Natural Gas Liquids segment’s pipeline tariffs provide us the ability to require security from shippers.

Natural Gas Pipelines - Our Natural Gas Pipelines segment’s customers are primarily local natural gas distribution companies, electric-generation facilities, large industrial companies, municipalities, producers, processors and marketing companies. In 2025 and 2024, excluding EnLink in 2024, approximately 80% and 90%, respectively, of our revenues in this segment were from customers rated investment-grade by S&P, approved through comparable internal counterparty analysis or were secured by letters of credit or other collateral. In addition, the majority of our pipeline tariffs in this segment provide us the ability to require security from shippers.

Refined Products and Crude - Our Refined Products and Crude segment’s customers include refiners, wholesalers, retailers, traders, railroads, airlines and regional farm cooperatives. In 2025 and 2024, excluding EnLink and Medallion in 2024, approximately 85% and 70%, respectively, of our revenues in this segment were from customers rated investment-grade by S&P, approved through comparable internal counterparty analysis or were secured by letters of credit, liens, or other collateral.

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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,

(Millions of dollars, except per share amounts)

Revenues

Transaction costs (Note B) 81 73 158

Other operating income, net (Notes A and B) (43) (305) (786)

Equity in net earnings from investments (Note N) 386 439 202

Less: Net income attributable to noncontrolling interests 69 77 —

Less: Preferred stock dividends — 1 1

Net income available to common shareholders $ 3,393 $ 3,034 $ 2,658

Average shares (millions)

See accompanying Notes to Consolidated Financial Statements.

ONEOK, Inc. and Subsidiaries

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

Years Ended December 31,

(Millions of dollars)

Other comprehensive income (loss), net of tax

Total other comprehensive income (loss), net of tax 69 (63) 75

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,

Assets (Millions of dollars)

Current assets

Cash and cash equivalents $ 78 $ 733

Property, plant and equipment

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

Intangible assets, net (Note F) 2,901 3,039

Liabilities and equity

Current liabilities

Current maturities of long-term debt (Note G) $ 1,241 $ 1,059

Short-term borrowings (Note G) 820 —

Other current liabilities 750 702

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

Total deferred credits and other liabilities 6,952 6,199

Commitments and contingencies (Note O)

Equity (Note H)

Accumulated other comprehensive loss (27) (96)

Noncontrolling interests in consolidated subsidiaries 84 5,097

See accompanying Notes to Consolidated Financial Statements.

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ONEOK, Inc. and Subsidiaries

CONSOLIDATED STATEMENTS OF CASH FLOWS

Years Ended December 31,

(Millions of dollars)

Operating activities

Equity in net earnings from investments (Note N) (386) (439) (202)

Distributions received from unconsolidated affiliates 397 390 202

Gain on sale of business (Note B) — (227) —

Medford settlement gain (Note A) — — (779)

Medford settlement proceeds (Note A) — — 502

Changes in assets and liabilities:

Inventories, net of commodity imbalances (263) 17 118

Other assets and liabilities, net (105) (223) 195

Investing activities

Cash paid for acquisitions, net of cash acquired (25) (5,829) (5,015)

Proceeds from the sale of business (Note B) — 1,200 —

Medford settlement proceeds (Note A) — — 328

Financing activities

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) —

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

(Millions of dollars)

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)

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

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

*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 tothe 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

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.

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:

(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

Total cash consideration $ 3,285

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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

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:

OKE US Equity

OKE · 10-K · period ended 2025-12-31

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

OKE US Equity☆

OKE · 10-K · period ended 2025-12-31

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

OKE US Equity