ONEOK INC /NEW/ (Form: 10-K, Received: 02/23/2021 16:11:07)

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{00113938 2 } ONEOK, INC. 2020 NONQUALIFED DEFERRED COMPENSATION PLAN (Effective January 1, 2020) Exhibit 10.40

{00113938 2 } TABLE OF CONTENTS ARTICLE 1. PURPOSE AND EFFECTIVE DATE ...................................................................... 1 1.1 Purpose ............................................................................................................................ 1 1.2 Effective Date ................................................................................................................. 1 1.3 Definitions....................................................................................................................... 1 ARTICLE 2. PARTICIPATION .................................................................................................... 2 2.1 Commencement of Participation..................................................................................... 2 2.2 Special Rule for Initial Participation ............................................................................... 2 2.3 Termination of Participation ........................................................................................... 2 ARTICLE 3. PARTICIPANT ELECTIVE CONTRIBUTIONS ................................................... 3 3.1 Deferral Agreement ........................................................................................................ 3 3.2 Amount of Deferral ......................................................................................................... 3 3.3 Evergreen ........................................................................................................................ 3 3.4 Timing of Election .......................................................................................................... 3 3.5 Irrevocability, Generally ................................................................................................. 4 3.6 Withholding of Deferrals ................................................................................................ 4 ARTICLE 4. EMPLOYER CONTRIBUTIONS ............................................................................ 5 4.1 Employer Contributions .................................................................................................. 5 4.2 Timing of Employer Contributions ................................................................................. 5 ARTICLE 5. PAYMENT SCHEDULE AND FORM OF PAYMENT ......................................... 6 5.1 Distribution Date ............................................................................................................. 6 5.2 Form of Distribution. ...................................................................................................... 6 5.3 Unforeseeable Emergency .............................................................................................. 6 5.4 Distributions to Specified Employees ............................................................................. 6 5.5 Subsequent Elections ...................................................................................................... 6 ARTICLE 6. SPECIAL DISTRIBUTION RULES ........................................................................ 8 6.1 Permissible Accelerations of Distributions ..................................................................... 8 6.2 Permissible Delays in Payment ....................................................................................... 9 6.3 General Timing Rules ..................................................................................................... 9 ARTICLE 7. ACCOUNTS AND CREDITS/OTHER ADJUSTMENTS .................................... 11 7.1 Contribution Credits to Account ................................................................................... 11 7.2 Vesting .......................................................................................................................... 11 7.3 Earnings Credits to Account ......................................................................................... 11 7.4 Adjustment of Accounts ............................................................................................... 11 ARTICLE 8. AMENDMENT AND TERMINATION ................................................................ 12 8.1 Amendment by Employer ............................................................................................. 12 8.2 Plan Terminations ......................................................................................................... 12 ARTICLE 9. PLAN ADMINISTRATION................................................................................... 13 9.1 Committee; Duties ........................................................................................................ 13 9.2 Binding Effect of Decisions .......................................................................................... 13 9.3 Delegation of the Committee’s Powers and Responsibilities ....................................... 13 9.4 Indemnification ............................................................................................................. 14 9.5 Claims and Review Procedures .................................................................................... 14 9.6 Disability Determinations ............................................................................................. 17

{00113938 2 } ARTICLE 10. MISCELLANEOUS ............................................................................................. 18 10.1 Unsecured General Creditor of the Employer .............................................................. 18 10.2 Trusts; Transfers of Assets, Property ............................................................................ 18 10.3 Section 409A ................................................................................................................. 18 10.5 Limitation of Rights ...................................................................................................... 18 10.6 Anti-Assignment ........................................................................................................... 18 10.7 Facility of Payment ....................................................................................................... 19 10.8 Notices .......................................................................................................................... 19 10.9 Tax Withholding ........................................................................................................... 19 10.10 No Guarantee or Employment or Participation ............................................................ 19 10.11 Unclaimed Benefit ........................................................................................................ 19 10.12 Governing Law ............................................................................................................. 20 10.13 Erroneous Payment ....................................................................................................... 20 ARTICLE 11. DEFINITIONS ...................................................................................................... 21

{00113938 2 } 1 ARTICLE 1. PURPOSE AND EFFECTIVE DATE 1.1 Purpose. The purpose of the Plan is to provide a select group of primarily management or highly compensated employees of the Employer the option to defer the receipt of portions of their compensation payable for services rendered to the Employer, and provide nonqualified deferred compensation benefits which are not available to such employees by reason of limitations on employer and employee contributions to qualified pension or profit-sharing plans under the federal tax laws. 1.2 Effective Date. The ONEOK, Inc. 2020 Nonqualified Deferred Compensation Plan is effective January 1, 2020, with respect to Base Compensation for payroll periods ending, and Incentive Compensation for services provided, on or after the Effective Date. 1.3 Definitions. Capitalized terms are defined in ARTICLE II.

{00113938 2 } 2 ARTICLE 2. PARTICIPATION 2.1 Commencement of Participation. Each Eligible Employee shall become a Participant either upon the earlier of (i) the initial submission of an Election, or (ii) first receiving an allocation of Employer Contributions or Supplemental Retirement Contributions. 2.2 Special Rule for Initial Participation. Within 30 days after the date an individual first becomes an Eligible Employee, the individual may elect to commence participating with respect to compensation to be paid for services performed after the election is filed. This election relating to initial participation in the Plan is available only to Participants who do not participate in any Aggregated Plans. If an Employee whose participation in the Plan is terminated again becomes an Eligible Employee, he or she may elect to defer pursuant to this Section only if the Employee was ineligible to defer compensation in any Aggregated Plans for the 24 months preceding the date on which the Participant again became eligible to participate in this Plan. 2.3 Termination of Participation Subject to Section 3.5, regarding the irrevocability of a Participant’s Election, the Committee may, for any reason, terminate a Participant's participation in the Plan and the Participant shall cease to be an Eligible Employee as of the date specified by the Committee. The terms of this Plan shall continue to govern Participant’s Account until the Participant’s Account is paid in full.

{00113938 2 } 3 ARTICLE 3. PARTICIPANT ELECTIVE CONTRIBUTIONS 3.1 Deferral Agreement. Base Compensation. Each Eligible Employee may defer a portion of Base Compensation for such upcoming Plan Year by executing an Election deferring such Base Compensation during the Election Period. Incentive Compensation. Each Eligible Employee may defer a portion of Incentive Compensation for such upcoming Plan Year by executing an Election deferring such Incentive Compensation during the Election Period. 3.2 Amount of Deferral. An Eligible Employee may elect to defer between 2% and 90% of his or her Base Compensation and between 10% and 90% of his or her Incentive Compensation for a Plan Year; provided, however, that such deferrals shall be made in whole percentages. The deferral amount is the amount designated on the Participant’s Election. 3.3 Evergreen. A Participant’s Election shall remain in full force and effect for all subsequent years until modified or revoked in writing during an Election Period or terminated in accordance with Section 3.5. If a Participant’s Election has been deemed continued for a Plan Year in accordance with this Section, it is irrevocable for such Plan Year. 3.4 Timing of Election. Incentive Compensation. The Election Period for Incentive Compensation shall be within the fourth fiscal quarter of the calendar year immediately preceding the calendar year in which the Incentive Compensation is earned with the specific time period determined annually in the discretion of the Committee (or designee thereof). Subject to Section 3.3, above, if a Participant desires to amend or modify the deferral of Incentive Compensation a new Election must be timely executed for each Plan Year during the applicable Election Period. An Eligible Employee who does not timely execute an Election during his or her initial Election Period to defer Incentive Compensation shall be deemed to have elected zero deferrals of Incentive Compensation for such Plan Year and each subsequent Plan Year until a timely Election is made. Notwithstanding the foregoing, in the discretion of the Committee, the Committee may provide that the Election Period for Incentive Compensation (that also qualifies as performance based compensation within the meaning of Section 409A) for a Plan Year may begin on June 1st and end on June 30th of that Plan Year. If the Committee provides such Election Period for Incentive Compensation, in no event shall the last day of any Election Period to defer Incentive Compensation be later then the date that is six months before the end of the performance period, provided that the Participant performs services continuously from the later of the beginning of the performance period or the date the performance criteria are established through the date an election is made, and provided further that in no event may any Participant elect to defer Incentive Compensation after such compensation has become readily ascertainable.

{00113938 2 } 4 Base Compensation. The Election Period for Base Compensation shall be within the fourth calendar quarter of the year immediately preceding the calendar year in which the Base Compensation is earned with the specific time period determined annually in the discretion of the Committee (or designee thereof). Subject to Section 3.3, above, if a Participant desires to amend or modify the deferral of Base Compensation a new Election must be timely executed for each Plan Year during the applicable Election Period. An Eligible Employee who does not timely execute an Election during his or her initial Election Period shall be deemed to have elected zero deferrals of Base Compensation for such Plan Year and each subsequent Plan Year until a timely Election is made. Pre-Effective Date Election Period. For purposes of the initial Plan Year beginning January 1, 2020, the Election Period for Eligible Employees prior to the Effective Date of the Plan (who are identified to as eligible to become Participants in the Plan on January 1, 2020) shall be established by and in the Committee’s discretion during the period of October 1, 2019 through December 31, 2019 and shall apply to all Base Compensation for payroll periods ending, and Incentive Compensation for services provided, on or after the Effective Date. 3.5 Irrevocability, Generally. Except as otherwise provided in Section 3.4, an Election with respect to a Plan Year may not be changed or revoked for that Plan Year after the last day of the Election Period. A Participant's deferral Election for the remainder of the Plan Year will be cancelled on account of the Participant's Disability in accordance with Treasury Regulation Section 1.409A-3(j)(4)(xii). 3.6 Withholding of Deferrals. The Employer shall have the sole discretion to withhold the percentage of Base Compensation, and Incentive Compensation specified in a Participant’s Election for a Plan Year at the times and in the amounts that the Employer, in its sole discretion, selects, which need not be uniform either among Participants or as to payments to a single Participant; provided, however, that deferral amounts must be withheld not later than the end of the calendar year during which the Company would otherwise have paid the amounts to the Participant but for the Participant’s Election. Deferrals of Base Compensation shall not be withheld during any period in which the Participant is on an unpaid leave of absence. All deferral amounts that are withheld in accordance with this Section shall be deemed for all purposes to comply with the Plan requirements regarding deferrals.

{00113938 2 } 5 ARTICLE 4. EMPLOYER CONTRIBUTIONS 4.1 Employer Contributions. Employer Contribution. Each Plan Year, the Employer shall credit to the Account of each Participant who is an Eligible Employee on the last day of the Plan Year (except for any Participant whose Separation from Service was as a result of death, Disability or Retirement) an amount equal 6% of Eligible Compensation. Supplemental Retirement Contribution Each Plan Year, the Employer shall credit to the Account of each Participant who is not eligible for or participating in the ONEOK, Inc. 2005 Supplemental Executive Retirement Plan during the Plan Year and who is an Eligible Employee on the last day of the Plan Year (except for any Participant whose Separation from Service was as a result of death, Disability or Retirement) a Supplemental Retirement Contribution in an amount equal to the total of subsections: (i), (ii), and (iii, if any) as described below: (i) An amount equal 1% of Eligible Compensation. (ii) A discretionary percentage of Eligible Compensation generally based on the profit sharing contribution issued for the Plan Year to eligible employees under the ONEOK, Inc. 401(k) Plan for the Plan Year. (iii) A supplemental amount determined by the Committee, in its sole discretion. 4.2 Timing of Employer Contributions. Employer Contributions and Supplemental Employer Contributions shall be credited to the Participant’s Account as soon as administratively practicable on or following the last day of each Plan Year.

{00113938 2 } 6 ARTICLE 5. PAYMENT SCHEDULE AND FORM OF PAYMENT. Subject to ARTICLE 6, Plan Accounts shall be distributed in accordance with the provisions of this Article. 5.1 Distribution Date. Amounts allocated to the Participant's Account shall be paid, or begin to be paid, upon the earliest of: (i) a date, specified in the Participant’s Election, that is no earlier than the January 1 following the 5th anniversary of the Participant’s Election; ii) the Participant’s Separation from Service; (iii) the Participant’s death; (iv) the Participant’s Disability, or (v) a Change in Control. If a Participant does not have an Election with respect to contributions for specific Plan Year, including an evergreen Election pursuant to Section 3.3, or if for any reason the Participant’s Election for a Plan Year is invalid, the Participant’s Account attributable to that Plan Year shall be paid upon the Participant’s Separation from Service. 5.2 Form of Distribution. Upon the occurrence of a distribution date in Section 5.1, the Participant's Account shall be paid, or begin to be paid, in one of the following forms as specified in the Participant’s Election (or Subsequent Election): (i) a single lump sum; (ii) annual installments over 5 years; or (iii) annual installments over 10 years. Notwithstanding the foregoing, at any time and in its discretion, the Committee may determine that the number of separate Elections as to the time and form of a distribution shall be limited. Following the Committee’s decision to implement a limit, any Participant Election specifying additional times and forms of distribution in excess of such limit will be invalid. In the event there is no Participant Election with respect to a Participant’s contributions for a specific Plan Year, or if for any reason the Participant’s Election for a Plan Year is invalid, that portion of a Participant’s Account shall be paid in a single lump sum. 5.3 Unforeseeable Emergency. A Participant may submit a written request for a distribution on account of an Unforeseeable Emergency. Upon approval by the Committee of a Participant’s request, the Participant’s Account, or that portion of a Participant’s Account deemed necessary by the Committee to satisfy the Unforeseeable Emergency (determined in a manner consistent with Section 409A) plus amounts necessary to pay taxes reasonably anticipated because of the distribution, will be distributed in a single lump sum. 5.4 Distributions to Specified Employees. Notwithstanding any other provision of the Plan, if any payment or benefit provided to a Participant in connection with his or her Separation from Service is determined to constitute "nonqualified deferred compensation" within the meaning of Section 409A of the Code and the Participant is determined to be a "specified employee" as defined in Section 409A(a)(2)(b)(i) of the Code, then such payment or benefit shall not be paid, or commence to be paid, until (i) the first payroll date to occur following the six-month anniversary of the Separation from Service; or (ii) if earlier, on the Participant’s death (the "Specified Employee Payment Date"). 5.5 Subsequent Elections. In accordance with rules, procedures and forms specified from time to time by the Committee, a Participant may file a Subsequent Election to change the time on which the distribution is to commence or the form in which the Participant’s Account is

{00113938 2 } 7 distributed, or both. A Participant may file a Subsequent Election only if it complies with the provisions of section 409A of the Code and Treasury Regulations and the following conditions are met: The Subsequent Election shall not take effect until at least twelve (12) months after the date on which it is made; Except in the case of an election permitted under Section 409A and the Treasury Regulations §1.409A-3(a)(2) (payment on account of disability), § 1.409A-3(a)(3) (payment on account of death), or §1.409A-3(a)(6) (payment on account of the occurrence of an unforeseeable emergency), the payment with respect to which such Subsequent Election shall be deferred for a period of five (5) years from the date such payment would otherwise have been paid (or in the case of installment payments treated as a single payment, five (5) years from the date the first amount was scheduled to be paid); and Any Subsequent Election related to a payment described in Treasury Regulations §1.409A-3(a)(4) (payment at a specified time or pursuant to a fixed schedule) shall be made not less than twelve (12) months before the date the payment is scheduled to be paid (or in the case of a life annuity or installment payments treated as a single payment, twelve (12) months before the date the first amount was scheduled to be paid). A Participant who has made a prior Subsequent Election under the Plan shall be allowed to make another Subsequent Election in accordance with this Section 5.5 and other provisions of the Plan. The Committee, or its designee, shall be authorized to administer, construe and interpret the foregoing provisions and the Plan with respect to all Subsequent Elections to assure compliance with the intent thereof and the requirements of the Plan and of Section 409A of the Code and Treasury Regulations.

{00113938 2 } 8 ARTICLE 6. SPECIAL DISTRIBUTION RULES 6.1 Permissible Accelerations of Distributions Except as otherwise provided in the Plan and except as may be allowed in guidance from the Secretary of the Treasury, distributions from a Participant’s Account may not be made earlier than the time such amounts would otherwise be distributed pursuant to the terms of the Plan. Taxes. The Employer, in its sole discretion, may accelerate the time in which payment shall be made under the Plan to: (a) pay the FICA tax imposed under Code Sections 3101, 3121(a) and 3121(v)(2) on compensation deferred under the Plan, (b) pay the income tax at source on wages imposes under Code Section 3401 or the corresponding withholding provisions of the applicable, state, local or foreign tax laws as a result of the payment of any FICA tax described in clause (a), and to pay the additional income tax at source on wages attributable to the pyramiding Code Section 3401 wages and taxes, (c) pay state, local, or foreign tax obligations arising from participation in the Plan that apply to an amount deferred under the Plan before the amount is paid or made available to the Participant, (d) pay the income tax at source on wages imposed under Code Section 3401 as a result of the payment described in clause (d) and to pay the additional income tax at source on wages imposed under Code Section 3401 attributable to such additional Code Section 3401 wages and taxes, (e) pay the amount required to be included in gross income as a result of the failure of the Plan to comply with the requirements of Code Section 409A. The total payment under clauses (a) and (b) shall, in no event, exceed the aggregate of the FICA tax and the income tax withholding related to such FICA tax. The total payment under clause (c) shall, in no event, exceed the amount of such taxes due as a result of participation in the Plan. The total payment under clauses (c) and (d) shall, in no event, exceed the aggregate of the state, local, and foreign tax amount, and the income tax withholding related to such state, local, and foreign tax amount. The total payment under clause (e) shall, in no event, exceed the amount required to be included in income as a result of the failure to comply with requirements of Code Section 409A. Compliance with Ethics Laws or Conflicts of Interests Laws. The Committee is authorized, in its sole discretion, to accelerate the time or schedule of a payment to the extent reasonably necessary to avoid the violation of an applicable federal, state, local, or foreign ethics law or conflicts of interest law (including where such payment is reasonably necessary to permit the Participant to participate in activities in the normal course of his position in which the Participant would otherwise not be able to participate under an applicable rule), determined in accordance with Section 409A. Small Accounts. The Committee may, in its sole discretion, distribute in a single lump sum the aggregate amounts credited to the Participant’s Account, along with any related earnings, provided: (i) the distribution results in the payment of the Participant’s entire interest in the Account and all Aggregated Plans, and (ii) the total payment does not exceed the applicable dollar limit under Code section 402(g)(1)(B). The Committee shall notify the Participant in writing if the Committee exercises its discretion pursuant to this Section.

{00113938 2 } 9 Settlement of a Bona Fide Dispute. The Committee may, in its sole discretion, accelerate the time or schedule of a distribution as part of a settlement of a bona fide dispute between the Participant and the Employer over the Participant’s right to a distribution provided that the distribution relates only to the deferred compensation in dispute and the Employer is not experiencing a downturn in financial health. Settlement of Debt. The Committee may, in its sole discretion, accelerate the time or schedule of a payment to satisfy the debt of a Participant to the Employer or any Related Employer where such debt is incurred in the ordinary course of the service relationship between the Participant and the Employer or Related Employer, as applicable, the entire amount of the reduction in any Plan year does not exceed $5,000, and the reduction is made at the same time and in the same amount as the debt otherwise would have been due and collected from the Participant. 6.2 Permissible Delays in Payment. Distributions may be delayed beyond the date payment would otherwise occur in accordance with the Plan in any of the following circumstances: Payments that would violate Federal Securities Laws or Other Applicable Law. The Employer may also delay payment if it reasonably anticipates that the marking of the payment will violate Federal securities laws or other applicable laws provided payment is made at the earliest date on which the Employer reasonably anticipates that the making of the payment will not cause such violation. Going Concern. If the distribution would jeopardize the Employer’s ability to continue as a going concern, provided that the delayed amount is distributed in the first calendar year in which the payment would not have such effect. Inability to Calculate. If calculation of the amount of the payment is not administratively practicable due to events beyond the control of the Participant (or Participant's Beneficiary), the payment will be treated as made upon the date contemplated by the Plan if the payment is made during the first calendar year in which the payment is administratively practicable. Other Events and Conditions. The Employer also reserves the right to delay payment upon such other events and conditions as the Secretary of the Treasury may prescribe in generally applicable guidance published in the Internal Revenue Bulletin. 6.3 General Timing Rules. The general rules in this section shall apply to all Plan distributions. Except as otherwise provided in this section, if a distribution is required upon the occurrence of an event specified in Section 5.1, the distribution will commence between the date of the distribution event and the later of (i) the end of the year in which the distribution event occurs, and (ii) 15th day of the third calendar month following the distribution event; provided, however, the Participant will not be permitted, directly or indirectly, to designate the taxable year of the

{00113938 2 } 10 distribution. If a Participant has elected to receive a distribution commencing during a specific calendar year, the distribution may occur any time during that year; provided, however, that if an Participant’s Election specifies a particular month during which the distribution should commence, the distributions may not commence before the first day of the specified month. Any distribution that complies with this section shall be deemed for all purposes to comply with the Plan requirements regarding the time and form of distributions.

{00113938 2 } 11 ARTICLE 7. ACCOUNTS AND CREDITS/OTHER ADJUSTMENTS 7.1 Contribution Credits to Account. A Participant's Account will be credited for each Plan Year with: (a) the amount of the Participant’s elective deferrals in accordance with ARTICLE 3, and the amount of any Employer Contributions or Supplemental Retirement Contributions credited on his behalf annually under ARTICLE 4. Separate Accounts shall be maintained for each Participant for each Plan Year for which contributions are credited to the Participant. 7.2 Vesting. A Participant shall always be 100% vested in all contributions allocated to the Participant’s Account. 7.3 Earnings Credits to Account. The Participant's Account shall be credited (or debited) on each Valuation Date with income (or loss) based upon a hypothetical investment in any one or more of the investment options available under the Plan, as prescribed by the Committee. In the absence of any affirmative investment decision by the Committee (or any delegate thereof), the investment options available under the Plan shall mirror the then current investment options offered to participants under the ONEOK, Inc. 401(k) Plan (or any successor thereto), excluding common stock of the Employer and any investment fund frozen to new contributions. The crediting or debiting on each Valuation Date of income (or loss) shall be made for each respective Account. All investments of a Participant’s Account shall be valued at fair market value. Additionally, all distributions, investments and investment exchanges allowed and made under the Plan shall be as of the relevant Valuation Date at fair market value. 7.4 Adjustment of Accounts. Each Account maintained for a Participant shall be adjusted for interest credits and any expenses allocable under the terms of the Plan to the Account. The Account shall be adjusted as of each Valuation Date to reflect: (a) the earnings credits and expenses described under Section 7.3, above; (b) amounts credited pursuant to ARTICLE 3 and ARTICLE 4; and (c) distributions or withdrawals.

{00113938 2 } 12 ARTICLE 8. AMENDMENT AND TERMINATION 8.1 Amendment by Employer. The Employer may at any time amend the Plan in whole or in part, except that no amendment may reduce the value of any Participant’s Account. An amendment must be in writing and executed by a representative of the Employer authorized to take such action. 8.2 Plan Terminations. The Employer retains the discretion to terminate the Plan and distribute each Participant’s Account in a single lump sum if (1) the termination does not occur proximate to a downturn in the financial health of the Employer; (2) all Aggregated Plans are terminated, (3) no payments other than payments that would be payable under the terms of the arrangements if the termination had not occurred are made within 12 months of the termination of the arrangements, (4) all payments are made within 24 months of the termination of the arrangements, and (5) neither the Employer nor any Related Employer adopts a new arrangement that would be aggregated with any terminated arrangement under Treasury Regulation Section 1.409A-1(c), if the same service provider participated in both arrangements, at any time with the three year period following the date of termination of the arrangement. Automatic Termination following distribution of all Accounts. The Plan will terminate automatically as of the date that no amounts remain to be distributed under the Plan. In connection with change in control. The Employer reserves the right to terminate the Plan and accelerate the time of payment of all amounts to be distributed under the Plan in accordance with the following provisions of this Section 8.2. The Employer may make an irrevocable election to terminate the Plan and distribute all amounts credited to all Participant Accounts within the 30 days preceding or the 12 months following a Change in Control. For this purpose, the Plan will be treated as terminated only if all other Aggregated Plans are terminated and liquidated with respect to each Participant that experienced the Change in Control, so that under the terms of the termination and liquidation all such Participants are required to receive all amounts of compensation deferred under the terminated arrangements within 12 months of the date the Employer irrevocably takes all necessary action to terminate and liquidate the Plan and such other arrangements.

{00113938 2 } 13 ARTICLE 9. PLAN ADMINISTRATION 9.1 Committee; Duties. This Plan shall be administered by the Committee. The Committee shall have the authority to make, amend, interpret and enforce all appropriate rules and regulations for the administration of the Plan and decide or resolve any and all questions, including interpretations of the Plan, as they may arise in such administration. 9.2 Binding Effect of Decisions. The decision or action of the Committee with respect to any question arising out of or in connection with the administration, interpretation and application of the Plan and the rules and regulations promulgated hereunder shall be final, conclusive and binding upon all persons having any interest in the Plan. 9.3 Delegation of the Committee’s Powers and Responsibilities. The Committee may appoint an entity or individual, who may be an employee of the Employer or a third party, to be the Committee’s agent with respect to the day-to-day administration of the Plan. In addition, the Committee may, from time to time, employ other agents and delegate to them such administrative duties as it sees fit, and may from time to time consult with counsel who may be counsel to the Employer. Except for settlor duties and responsibilities that are specifically reserved to the Employer, the Board or the Committee (including, but not limited to, the ability to terminate the Plan or approve amendments to the Plan), or which have been properly delegated to another person or entity under the terms of the Plan, all settlor duties and responsibilities with respect to the Plan are delegated to the ONEOK, Inc. Benefit Plan Sponsor Committee, with the exception of the following duties and responsibilities which shall be delegated to the President and Chief Executive Officer of the Employer: (i) Amendments which constitute routine, ministerial, clarifying or conforming amendments and do not materially modify the provision or intent of the Plan; (ii) To decide all questions concerning the Plan and the eligibility of any person to participate in the Plan, in its sole discretion, subject to review by the Committee; and (iii) To determine the amount of any benefit or contribution or to increase any benefit or contribution under the Plan (except for such increases which related to the delegate’s own deferred compensation), so long as such increase does not exceed One Million Dollars ($1,000,000) for any Plan Year. Except for such duties and responsibilities as may be specifically reserved to the Employer, the Board, the Committee or the ONEOK, Inc. Benefit Plan Sponsor Committee, or which have been properly delegated to another person or entity under the terms of the Plan, the

{00113938 2 } 14 ONEOK, Inc. Benefit Plan Administration Committee shall be responsible for the discretionary administration of the Plan. 9.4 Indemnification. To the fullest extent allowed by law, the Employer shall indemnify and hold harmless each member of the Committee and each employee, officer, or director of the Employer or any Related Employer to whom is delegated duties, responsibilities, and authority with respect to the Plan against all claims, liabilities, fines and penalties, and all expenses reasonably incurred by or imposed upon him (including but not limited to reasonable attorneys' fees) which arise as a result of his actions or failure to act in connection with the operation and administration of the Plan to the extent lawfully allowable and to the extent that such claim, liability, fine, penalty, or expense is not paid for by liability insurance purchased or paid for by the Employer or and Related Employer. Notwithstanding the foregoing, the Employer shall not indemnify any person for any such amount incurred through any settlement or compromise of any action unless the Employer consents in writing to such settlement or compromise. 9.5 Claims and Review Procedures Claims Procedure. If any person believes he is being denied any rights or benefits under the Plan, such person (the “Claimant”) may file a claim in writing with the Committee, or designee thereof (the “Claims Administrator”). If any such claim is wholly or partially denied, the Claims Administrator will notify such person of its decision in writing. Such notification will contain (i) specific reasons for the denial, (ii) specific reference to pertinent Plan provisions, (iii) a description of any additional material or information necessary for such person to perfect such claim and an explanation of why such material or information is necessary, and (iv) information as to the steps to be taken if the person wishes to submit a request for review. Such notification will be given within 90 days after the claim is received by the Claims Administrator (or within 180 days, if special circumstances require an extension of time for processing the claim, and if written notice of such extension and circumstances is given to such person within the initial 90 day period). If such notification is not given within such period, the claim will be considered denied as of the last day of such period and such person may request a review of his claim. Review Procedure. Within 60 days after the date on which a person receives a written notification of denial of claim (or, if written notification is not provided, within 60 days of the date denial is considered to have occurred), such person (or his duly authorized representative) may (i) file a written request with the Claims Administrator for a review of his denied claim and of pertinent documents and (ii) submit written issues and comments to the Claims Administrator. The Claims Administrator will notify such person of its decision in writing. Such notification will be written in a manner calculated to be understood by such person and will contain specific reasons for the decision as well as specific references to pertinent Plan provisions. The decision on review will be made within 60 days after the request for review is received by the Claims Administrator (or within 120 days, if special circumstances require an extension of time for processing the request, such as an election by the Claims Administrator to hold a hearing, and if written notice of such extension and circumstances is given to such person within the initial 60-day period). If the decision on review is not made within such period, the claim will be considered

{00113938 2 } 15 denied. Except as otherwise provided in Section 9.5, the decision, action or inaction of the Claims Administrative shall be final, conclusive and binding on all persons having an interest in the Plan. Mandatory Arbitration. If, after exhausting the procedures set forth in this Section, a Claimant wishes to pursue legal action, any action by the Claimant with respect to a claim made under Section 9.5, must be resolved by arbitration in the manner described in this Section. This agreement to arbitrate shall be specifically enforceable. A party may apply to the United States District Court for the Northern District of Oklahoma for interim, injunctive or conservatory relief, including without limitation a proceeding to compel arbitration. If the arbitration provisions herein are determined by any court to be unenforceable, any further legal action must be filed only in the United States District Court for the Northern District of Oklahoma within the time limits, and shall be subject to the standard of review, all as set forth below. (i) Time Limits. A Claimant seeking arbitration of any determination of the Claims Administrator must, within six (6) months of the date of the Claims Administrator’s final decision, file a demand for arbitration with the American Arbitration Association submitting the claim to resolution by arbitration. A Claimant waives any claim not filed timely in accordance with this Section. (ii) Rules Applicable to Arbitration. The arbitration process shall be conducted in accordance with the Commercial Law Rules of the American Arbitration Association. (iii) Venue. The arbitration shall be conducted in Tulsa, Oklahoma. (iv) Binding Effect. The decision of the arbitrator with respect to the claim will be final and binding upon the Employer and the Claimant. By participating in the Plan, and accepting Plan Benefits, Participants, on behalf of themselves and any person with a Claim relating to Participant’s Plan Benefits, agree to waive any right to sue in court or to pursue any other legal right or remedy that might otherwise be available in connection with the resolution of the Claim. (v) Enforceability. Judgment upon any award entered by an arbitrator may be entered in any court having jurisdiction over the parties. (vi) Waiver of Class, Collective, and Representative Actions. Any claim shall be heard without consolidation of such claims with any other person or entity. To the fullest extent permitted by law, whether in court or in arbitration, by participating in the Plan, Participants waive any right to commence, be a party to in any way, or be an actual or putative class member of any class, collective, or representative action arising out of or relating to any claim, and

{00113938 2 } 16 Participants agree that any Claim may only be initiated or maintained and decided on an individual basis. (vii) Standard of Review. Any decision of an Arbitrator on a claim shall be limited to determining whether the Claim Administrator’s decision or action was arbitrary or capricious or was unlawful. The Arbitrator shall adhere to and apply the deferential standard of review set out in Conkright v. Frommert, 559 U.S. 506 (2010), Metropolitan Life Insurance Co. v. Glenn, 554 U.S. 105 (2008), and Firestone Tire and Rubber Co. v. Bruch, 489 U.S. 101 (1989), and shall accord due deference to the determinations, interpretations, and construction of the Plan document of the Claims Administrator. (viii) General Procedures. (1) Arbitration Rules. The arbitration hearing will be conducted under the AAA Commercial Arbitration Rules (as amended or revised from time to time by AAA) (hereinafter the “AAA Rules”), before one AAA arbitrator who is from the Large, Complex Case Panel and who has experience with matters involving executive compensation and equity compensation plans. The AAA Rules and the terms and procedures set forth here may conflict on certain issues. To the extent that the procedures set forth here conflict with the AAA Rules, the procedures set forth here shall control and be applied by the arbitrator. Notwithstanding the amount of the claim, the Procedures for Large, Complex Commercial Disputes shall not apply. (2) Substantive Law. The arbitrator shall apply the substantive law (and the laws of remedies, if applicable), of Oklahoma or federal law, or both, depending upon the claim. Except to the extent required by applicable law, all arbitration decisions and awards shall be kept strictly confidential and shall not be disclosed by the Claimant to anyone other than the Claimant’s spouse, attorney or tax advisor. (3) Authority. The arbitrator shall have jurisdiction to hear and rule on prehearing disputes and is authorized to hold prehearing conferences by telephone or in person as the arbitrator deems necessary. The arbitrator will have the authority to hear a motion to dismiss and/or a motion for summary judgment by any party and in doing so shall apply the standards governing such motions under the Federal Rules of Civil Procedure.

{00113938 2 } 17 (4) Pre-Hearing Procedures. Each party may take the deposition of not more than one individual and the expert witness, if any, designated by another party. Each party will have the right to subpoena witnesses in accordance with the Arbitration Act. Additional discovery may be had only if the arbitrator so orders, upon a showing of substantial need. (5) Fees and Costs. Administrative arbitration fees and arbitrator compensation shall be borne equally by the parties, and each party shall be responsible for its own attorney’s fees, if any; provided, however, that the Committee will authorize payment by the Employer of all administrative arbitration fees, arbitrator compensation and attorney’s fees if the Committee concludes that a Claimant has substantially prevailed on his or her claims. Unless prohibited by statute, the arbitrator shall assess attorney’s fees against a party upon a showing that such party’s claim, defense or position is frivolous, or unreasonable, or factually groundless. If either party pursues a claim by any means other than those set forth in this Section, the responding party shall be entitled to dismissal of such action, and the recovery of all costs and attorney’s fees and losses related to such action, unless prohibited by statute. (ix) Interstate Commerce and the Federal Arbitration Act. The Employer is involved in transactions involving interstate commerce, and the employee’s employment with the Employer involves such commerce. Therefore, the Arbitration Act will govern the interpretation, enforcement, and all judicial proceedings regarding the arbitration procedures in this Section. 9.6 Disability Determinations. Whether a Participant has experienced a “Disability” as will be determined by the Social Security Administration or under the terms of the Company’s long-term disability plan in accordance with those claims procedures. The claims procedures set forth in this ARTICLE 9 will not apply to that question, but will apply to any other issues relating to Plan benefits.

{00113938 2 } 18 ARTICLE 10. MISCELLANEOUS 10.1 Unsecured General Creditor of the Employer. Participants and their Beneficiaries, heirs, successors and assigns shall have no legal or equitable rights, interests or claims in any property or assets of the Employer or any Related Employer. For purposes of the payment of benefits under the plan, the assets of the Employer or of any Related Employer shall be, and shall remain, the general, unpledged, unrestricted assets of the Employer or of such Related Employer, respectively. The Employer's obligation under the Plan shall be merely that of an unfunded and unsecured promise to pay money in the future. 10.2 Trusts; Transfers of Assets, Property. Notwithstanding the foregoing, in the event of a Change in Ownership or Control, the Employer shall create an irrevocable Trust, or before such time the Employer may create an irrevocable or revocable Trust, to hold funds to be used in payment of the obligations of the Employer or any Related Employer under the Plan. 10.3 Section 409A. It is intended that the Plan comply with the provisions of Section 409A, so as to prevent the inclusion in gross income of any amounts deferred hereunder in a taxable year that is prior to the taxable year or years in which such amounts would otherwise actually be paid or made available to Participants or Beneficiaries. This Plan shall be construed, administered, and governed in a manner that effects such intent, and the Committee shall not take any action that would be inconsistent with such intent. Each installment payment of compensation under this Plan shall be treated as a separate payment of compensation for purposes of applying Section 409A. Although the Committee shall use its best efforts to avoid the imposition of taxation, interest and penalties under Section 409A of the Code, the tax treatment of deferrals under this Plan is not warranted or guaranteed. Neither the Company, any Employer, the Board, any director, officer, employee and advisor, the Board nor the Committee (or any delegate thereof) shall be held liable for any taxes, interest, penalties or other monetary amounts owed by any Participant, Beneficiary or other taxpayer as a result of the Plan. The Committee is authorized to make any adjustments (including any additional contributions, offsets, recovery or recoupment) that it deems necessary or advisable, in its sole discretion, to comply with Code Section 409A. 10.4 Employer's Liability. The Employer's liability for the payment of benefits under the Plan shall be defined only by the Plan and by the Elections entered into between a Participant and the Employer. The Employer shall have no obligation or liability to a Participant under the Plan except as provided by the Plan and an Election. 10.5 Limitation of Rights. Neither the establishment of the Plan, nor any amendment thereof, nor the creation of any fund or account, nor the payment of any benefits, will be construed as giving to the Participant or any other person any legal or equitable right against the Employer, the Committee or any Related Employer except as provided herein; and in no event will the terms of employment or service of the Participant be modified or in any way affected hereby. 10.6 Anti-Assignment. No right or interest of the eligible employees or retirees under this Plan shall be subject to involuntary alienation, assignment or transfer of any kind. The

{00113938 2 } 19 Employer, the Board, the Committee and any of their delegates shall not review, confirm, guarantee or otherwise comment on the legal validity of any voluntary assignment. 10.7 Facility of Payment. If the Employer determines, on the basis of medical reports or other evidence satisfactory to the Employer, that the recipient of any benefit payments under the Plan is incapable of handling his affairs by reason of minority, illness, infirmity or other incapacity, the Employer may disburse such payments to a person or institution designated by a court which has jurisdiction over such recipient or a person or institution otherwise having the legal authority under State law for the care and control of such recipient. The receipt by such person or institution of any such payments, and any such payment to the extent thereof, shall discharge the liability of the Employer for the payment of benefits hereunder to such recipient. 10.8 Notices. Any notice or other communication required or permitted to be given in connection with the Plan shall be in writing and shall be deemed to have been duly given (i) upon request, if delivered personally or via courier, (ii) upon confirmation of receipt, if given by facsimile or electronic transmission, and (iii) on the third business day following mailing, if mailed first-class, postage prepaid, registered or certified mail as follows: If it is sent to the Employer or Employer, it will be at the address specified by the Employer; or If it is sent to a Participant or Beneficiary, it will be at the last address filed with the Employer by the Participant (or Beneficiary). 10.9 Tax Withholding. The Employer shall have the right to deduct from all payments or deferrals made under the Plan any tax required by law to be withheld. If the Employer concludes that tax is owing with respect to any deferral or payment hereunder, the Employer shall withhold such amounts from any payments due the Participant or his Beneficiary, as permitted by law, or otherwise make appropriate arrangements with the Participant or his Beneficiary for satisfaction of such obligation. Tax, for purposes of this section, means any federal, state, local, foreign or any other governmental income tax, employment or payroll tax, excise tax, or any other tax or assessment owing with respect to amounts deferred, any earnings thereon, and any payments made to Participants or Beneficiaries under the Plan. 10.10 No Guarantee or Employment or Participation. Nothing in the Plan shall interfere with or limit in any way the right of the Employer to terminate any Participant's employment at any time and for any reason, nor confer upon any Participant any right to continue in the employ of the Employer or any Related Employer. No employee of the Employer shall have a right to be selected as a Participant under the Plan or, if selected, to continue to participate for any Plan Year. 10.11 Unclaimed Benefit. Each Participant shall keep the Employer informed of his current address and the current address of his Beneficiary. The Employer shall not be obligated to search for the whereabouts of any person. If the location of a Participant is not made known to the Employer within three years after the date on which payment of the Participant's vested Account is

{00113938 2 } 20 scheduled to be made (or to commence), payment may be made as though the Participant had died at the end of the three-year period. If within one additional year after such three-year period has elapsed, or, within three years after the actual death of a Participant, the Employer is unable to locate the Beneficiary of the Participant, then the Employer shall have no further obligation to pay any benefit hereunder to such Participant or Beneficiary or any other person and such benefit shall be irrevocably forfeited. 10.12 Governing Law. The Plan will be construed, administered and enforced according to the laws of the State of Oklahoma without regard to principles of conflicts of law to the extent not otherwise preempted by the Code or by ERISA. 10.13 Erroneous Payment. Any amount paid under this Plan in error to a Participant or to a Participant's Beneficiary shall be returned to the Employer. A payment made in error does not create on the part of the recipient a legally binding right to such payment. In addition, the Plan and its agents are authorized to (A) recoup overpayments plus any earnings or interest, and (B) if necessary, offset any overpayments that are not returned against other Plan benefits to which the recipient is or becomes entitled.

{00113938 2 } 21 ARTICLE 11. DEFINITIONS Pronouns used in the Plan are in the masculine gender but include the feminine gender unless the context clearly indicates otherwise. Wherever used herein, the following terms have the meanings set forth below, unless a different meaning is clearly required by the context: “Account” means an account established for the purpose of recording amounts credited on behalf of a Participant, including (i) Participant deferrals of Base Compensation and Incentive Compensation; (ii) Employer Contributions; (iii) Supplemental Retirement Contributions; and (iv) any income, expenses, gains, losses or distributions included thereon. The Account shall be a bookkeeping entry only and shall be utilized solely as a device for the measurement and determination of the amounts to be paid to a Participant pursuant to the Plan. “Aggregated Plans” means this Plan or a portion of this Plan and all other non-qualified deferred compensation plans which must be aggregated with the Plan or portion of the Plan in accordance with the plan aggregation rules of Section 409A. “Base Compensation” means a Participant’s basic wage or salary paid by the Employer to the Participant without regard to any increases or decreases in such basic wage or salary as a result of (i) an Election to defer basic wage or salary under this Plan or (ii) an Election between benefits or cash provided under a plan of the Employer maintained pursuant to Sections 125 or 401(k) of the Code, after deductions and withholdings of all income and employment taxes and any other amounts required under uniform rules and procedures determined by the Committee and the Employer. The Base Compensation does not include any, long-term incentive awards or other cash bonus, stock or other equity paid to a Participant, nor any Incentive Compensation, as defined below. “Beneficiary” means the persons, trusts, estates or other entities designated in writing by a Participant, or otherwise entitled to receive benefits under the Plan upon the death of a Participant. If a Participant fails to designate a Beneficiary, then the Participant’s Beneficiary shall be the Participant’s spouse or, if the Participant does not have a spouse on the Participant’s date of death, the Participant’s estate. “Board” means the Board of Directors of ONEOK, Inc. “Change in Control” shall mean any of the following events: (a) a person (or more than one person acting as a group) acquires ownership of stock of the Company that, together with the stock held by such person or group, constitutes more than 50% of the total fair market value or total voting power of the stock of the Company; provided, that, a Change in Control shall not occur if any person (or more than one person acting as a group) owns more than 50% of the total fair market value or total voting power of the Company's stock and acquires additional stock; (b) one person (or more than one person acting as a group) acquires (or has acquired during the twelve-month period ending on the date of the most recent acquisition) ownership of the Company's stock possessing 30% or more of the total voting power of the stock of such corporation; (c) A majority of the members of the Board are replaced during any twelve-month period by directors whose appointment or election is

{00113938 2 } 22 not endorsed by a majority of the Board before the date of appointment or election; or (d) one person (or more than one person acting as a group), acquires (or has acquired during the twelve-month period ending on the date of the most recent acquisition) assets from the Company that have a total gross fair market value equal to or more than 40% of the total gross fair market value of all of the assets of the Company immediately before such acquisition(s). “Code” means the Internal Revenue Code of 1986, as amended. “Committee” means the Executive Compensation Committee of the Board or such other person(s) or committee(s) as may be appointed from time to time by the Board to supervise all or a portion of the administration of the Plan. Notwithstanding the foregoing, any ministerial duties assigned to the Committee pursuant to this Plan shall be able to be completed by a designee of the Committee in its discretion. To the extent that the Committee has delegated any of its duties and responsibilities, references to the Committee shall also refer to the delegate. “Disabled” or “Disability” means a determination that the Participant is, by reason of any medically determinable physical or mental impairment which can be expected to result in death or can be expected to last for a continuous period of not less than 12 months, receiving income replacement benefits for a period of not less than three months under an accident and health plan covering employees of the Employer or any Related Employer. A Participant also will be considered disabled if he is determined (a) to be totally disabled by the Social Security Administration, or (b) to be disabled in accordance with a disability insurance program, provided that the definition of disability applied under such disability insurance program complies with the requirements of Treasury Regulation Section 1.409A-3(i)(4). “Effective Date” generally means January 1, 2020. “Election” means a Participant’s notice, in the form and manner prescribed by the Committee, electing to defer payment of a portion of his or her Incentive Compensation or Base Compensation in accordance with ARTICLE 3, and specify the time and form of distribution of the deferred Incentive Compensation, Base Compensation, Supplemental Retirement Contributions or Employer Contributions, in accordance with ARTICLE 54, as well any evergreen election described in Section 3.3. Elections shall be irrevocable except as otherwise provided in the Plan or pursuant to Treasury guidance. “Election Period” means the applicable period during which an Eligible Employee must complete an Election. “Eligible Compensation” means, for any Plan Year, the total amount by which the sum of a Participant’s Base Compensation and Incentive Compensation exceeds the current compensation limit as stated in Code Section 401(a)(17) in effect for that Plan Year. “Eligible Employee” means an employee of the Employer who is designated by the Committee, by individual name or group or description as eligible to participate in the Plan and who is a management or highly compensated employee within the meaning of Sections 201(2), 301(a)(3) and 401(a)(1) of ERISA.

{00113938 2 } 23 “Employer” means ONEOK, Inc. or any successor entity thereto, and any Related Employer which permits its Employees to participate in the Plan. “Employer Contribution” means the contribution required by Section 4.1(a).“ERISA” means the Employee Retirement Income Security Act of 1974, as amended. “Incentive Compensation” means annual short-term bonuses paid to Eligible Employees under any applicable annual performance-based incentive compensation plans and which is not Base Compensation without regard to any decreases as a result of (i) an Election to defer all or any portion of such Incentive Compensation under this Plan or (ii) an Election between benefits or cash provided under any qualified retirement plan of the Employer maintained pursuant to Section 401(k) of the Code. Incentive Compensation does not include long-term incentive awards, stock, or other equity. “Participant” means an Eligible Employee who commences participation in the Plan in accordance with Article 2. “Plan” means this ONEOK, Inc. 2020 Nonqualified Deferred Compensation Plan, as amended from time to time. “Plan Year” means the calendar year. “Related Employer” means (a) any corporation that is a member of a controlled group of corporations as defined in Code Section 414(b) that includes the Employer, and (b) any trade or business that is under Common Control as defined in Code Section 414(c) that includes the Employer.“Retirement” means Separation from Service on or after age 50 with at least 5 years of service with any Related Employer. “Separation from Service” means a Participant's termination of employment with the Employer or Related Employer for any reason other than death that meets the requirements of the definition of "separation from service" set forth in Treasury Regulation Section 1.409A-1(h). For purposes of determining whether a Separation from Service has occurred, the 20% default threshold set forth in Treasury Regulation Section 1.409A-1(h)(1)(ii) shall be utilized. “Subsequent Election” means the election by a Participant to modify the time of distribution or form of payment of any prior Election in accordance with Section 5.5. “Supplemental Retirement Contribution” means the contribution(s) required by Section 4.1(b). “Unforeseeable Emergency” means an unanticipated emergency that is caused by an event beyond the control of the Participant that would result in severe financial hardship to the Participant resulting from (i) an illness or accident of the Participant or the Participant’s spouse, the Participant’s Beneficiary, or the Participant’s dependent (as defined in Code section 152, without regard to Code sections 152(b)(1), (b)(2), and (d)(1)(B)), (ii) a loss of the Participant’s property due to casualty, or (iii) such other similar extraordinary and unforeseeable circumstances arising as a result of events beyond the control of the Participant, all as determined in the sole discretion of the Administrator.

{00113938 2 } 24 “Valuation Date” means the date or dates specified by the Committee. As approved by the Executive Compensation Committee of the ONEOK, Inc. Board of Directors July 24, 2019.


Oklahoma			73-1520922
(State or other jurisdiction of incorporation or organization)			(I.R.S. Employer Identification No.)


Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common stock, par value of $0.01	OKE	New York Stock Exchange


Part I.		Page No.
Item 1.	Business	5
Item 1A.	Risk Factors	21
Item 1B.	Unresolved Staff Comments	33
Item 2.	Properties	33
Item 3.	Legal Proceedings	33
Item 4.	Mine Safety Disclosures	33
Part II.
Item 5.	Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	33
Item 6.	Selected Financial Data	35
Item 7.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	35
Item 7A.	Quantitative and Qualitative Disclosures about Market Risk	54
Item 8.	Financial Statements and Supplementary Data	57
Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	106
Item 9A.	Controls and Procedures	106
Item 9B.	Other Information	106
Part III.
Item 10.	Directors, Executive Officers and Corporate Governance	107
Item 11.	Executive Compensation	107
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	108
Item 13.	Certain Relationships and Related Transactions, and Director Independence	108
Item 14.	Principal Accounting Fees and Services	108
Part IV.
Item 15.	Exhibits, Financial Statement Schedules	109
Item 16.	Form 10-K Summary	117
Signatures		118


$1.5 Billion Term Loan Agreement			The senior unsecured delayed-draw three-year $1.5 billion term loan agreement dated November 19, 2018
$2.5 Billion Credit Agreement			ONEOK’s $2.5 billion revolving credit agreement, as amended
AFUDC			Allowance for funds used during construction
Annual Report			Annual Report on Form 10-K for the year ended December 31, 2020
ASU			Accounting Standards Update
Bbl			Barrels, 1 barrel is equivalent to 42 United States gallons
BBtu/d			Billion British thermal units per day
Bcf			Billion cubic feet
Bcf/d			Billion cubic feet per day

CARES Act			Coronavirus Aid, Relief, and Economic Security Act
CFTC			U.S. Commodity Futures Trading Commission
Clean Air Act			Federal Clean Air Act, as amended
Clean Water Act			Federal Water Pollution Control Act Amendments of 1972, as amended
COVID-19			Coronavirus disease 2019
DJ			Denver-Julesburg
DOT			United States Department of Transportation
EBITDA			Earnings before interest expense, income taxes, depreciation and amortization
EPA			United States Environmental Protection Agency
EPS			Earnings per share of common stock
Exchange Act			Securities Exchange Act of 1934, as amended
FERC			Federal Energy Regulatory Commission
Fitch			Fitch Ratings, Inc.
GAAP			Accounting principles generally accepted in the United States of America
GHG			Greenhouse gas
ICE			Intercontinental Exchange
Intermediate Partnership			ONEOK Partners Intermediate Limited Partnership, a wholly owned subsidiary of ONEOK Partners, L.P.
KCC			Kansas Corporation Commission
LIBOR			London Interbank Offered Rate
MBbl/d			Thousand barrels per day
MDth/d			Thousand dekatherms per day
MMBbl			Million barrels
MMBbl/d			Million barrels per day
MMBtu			Million British thermal units
MMcf/d			Million cubic feet per day
Moody’s			Moody’s Investors Service, Inc.
Natural Gas Act			Natural Gas Act of 1938, as amended
Natural Gas Policy Act			Natural Gas Policy Act of 1978, as amended
NGL(s)			Natural gas liquid(s)
NGL products			Marketable natural gas liquid purity products, such as ethane, ethane/propane mix, propane, iso-butane, normal butane and natural gasoline
Northern Border Pipeline			Northern Border Pipeline Company, a 50% owned joint venture
NYMEX			New York Mercantile Exchange
NYSE			New York Stock Exchange
OCC			Oklahoma Corporation Commission
ONEOK			ONEOK, Inc.
ONEOK Partners			ONEOK Partners, L.P., a wholly owned subsidiary of ONEOK, Inc.
ONEOK Partners Term Loan Agreement			The senior unsecured three-year $1.0 billion term loan agreement dated January 8, 2016, as amended


ONEOK West Texas NGL			ONEOK West Texas NGL pipeline and Mesquite pipeline (formerly known as West Texas LPG pipeline and Mesquite pipeline)
OPIS			Oil Price Information Service
Overland Pass Pipeline			Overland Pass Pipeline Company, LLC, a 50% owned joint venture
PHMSA			United States Department of Transportation Pipeline and Hazardous Materials Safety Administration
POP			Percent of Proceeds
Quarterly Report(s)			Quarterly Report(s) on Form 10-Q
Roadrunner			Roadrunner Gas Transmission, LLC, a 50% owned joint venture
RRC			Railroad Commission of Texas
S&P			S&P Global Ratings
SCOOP			South Central Oklahoma Oil Province, an area in the Anadarko Basin in Oklahoma
SEC			Securities and Exchange Commission
Securities Act			Securities Act of 1933, as amended
Series E Preferred Stock			Series E Non-Voting, Perpetual Preferred Stock, par value $0.01 per share
STACK			Sooner Trend Anadarko Canadian Kingfisher, an area in the Anadarko Basin in Oklahoma
Tax Cuts and Jobs Act			H.R. 1, the tax reform bill, signed into law on December 22, 2017
Topic 606			Accounting Standards Update 2014-09, “Revenue from Contracts with Customers”
WTI			West Texas Intermediate
XBRL			eXtensible Business Reporting Language


	Cumulative Total Return
	Years Ended December 31,
	2016		2017		2018		2019		2020

ONEOK, Inc.	$	249.37	$	244.18	$	259.53	$	383.51	$	217.21
S&P 500 Index	$	111.96	$	136.40	$	130.42	$	171.49	$	203.04
ONEOK Peer Group (a)	$	148.02	$	138.01	$	117.37	$	127.36	$	90.69
Alerian Midstream Energy Select Index (b)	$	143.55	$	144.65	$	119.08	$	145.69	$	111.56


Project (b)	Scope	Approximate Costs (a)	Completion
Natural Gas Gathering and Processing		(In millions)
Demicks Lake I plant and related infrastructure	200 MMcf/d processing plant and related gathering infrastructure in the core of the Williston Basin	$400	Completed October 2019
	Supported by acreage dedications with long-term primarily fee-based contracts
Demicks Lake II plant and related infrastructure	200 MMcf/d processing plant and related gathering infrastructure in the core of the Williston Basin	$410	Completed January 2020
	Supported by acreage dedications with long-term primarily fee-based contracts
Bear Creek plant expansion and related infrastructure	200 MMcf/d processing plant expansion and related gathering infrastructure in the Williston Basin	$405	Paused (c)
	Supported by acreage dedications with long-term primarily fee-based contracts




Natural Gas Liquids
Elk Creek pipeline and related infrastructure	900-mile NGL pipeline from the Williston Basin to the Mid-Continent region, with capacity of up to 240 MBbl/d, and related infrastructure	$1,400	Completed December 2019
	Anchored by long-term contracts
	Expansion capability up to 400 MBbl/d with additional pump facilities
Arbuckle II pipeline and related infrastructure	530-mile NGL pipeline from the STACK area to Mont Belvieu, Texas, and related infrastructure	$1,360	Completed March 2020
	Supported by long-term contracts
	Expansion capability up to 1 MMBbl/d
MB-4 fractionator and related infrastructure	125 MBbl/d NGL fractionator in Mont Belvieu, Texas, and related infrastructure, which includes additional NGL storage in Mont Belvieu	$575	Completed March 2020 (d)
	Fully contracted with long-term contracts
ONEOK West Texas NGL pipeline expansion and Arbuckle II connection	Increasing mainline capacity by 80 MBbl/d with additional pump facilities and pipeline looping	$295	Completed June 2020 (e)
	Connecting ONEOK West Texas NGL pipeline system to the Arbuckle II pipeline
	Supported by long-term dedicated production from six third-party processing plants expected to produce up to 60 MBbl/d
Bakken NGL pipeline extension	75-mile NGL pipeline in the Williston Basin connecting to a third-party processing plant	$100	Completed August 2020
	Supported by a long-term contract with a minimum volume commitment
Arbuckle II extension project and additional gathering infrastructure	Provide additional takeaway capacity in the STACK area	$240	Completed
	Allow increasing volumes on the Elk Creek pipeline access to fractionation capacity at Mont Belvieu, Texas		August 2020
Arbuckle II pipeline expansion	Increasing mainline capacity with additional pump facilities	$60	Paused (c)
	Increases capacity to 500 MBbl/d
MB-5 fractionator and related infrastructure	125 MBbl/d NGL fractionator in Mont Belvieu, Texas, and related infrastructure, which includes additional NGL storage in Mont Belvieu	$750	Paused (c)
	Fully contracted with long-term contracts
ONEOK West Texas NGL pipeline expansion	Increasing mainline capacity by 40 MBbl/d	$145	Paused (c)
	Supported by long-term dedicated production from third-party processing plants expected to produce up to 45 MBbl/d
Mid-Continent fractionation facility expansions	65 MBbl/d of expansions at our Mid-Continent NGL facilities	$150	Paused (c)


	Years Ended December 31,						2020 vs. 2019	2019 vs. 2018
Financial Results	2020		2019		2018		$ Increase (Decrease)
	(Millions of dollars, except per share amounts)
Revenues
Commodity sales	$	7,255.2	$	8,916.1	$	11,395.6	(1,660.9)	(2,479.5)
Services	1,287.0		1,248.3		1,197.6		38.7	50.7
Total revenues	8,542.2		10,164.4		12,593.2		(1,622.2)	(2,428.8)
Cost of sales and fuel (exclusive of items shown separately below)	5,110.1		6,788.0		9,422.7		(1,677.9)	(2,634.7)
Operating costs	886.1		982.9		907.0		(96.8)	75.9
Depreciation and amortization	578.7		476.5		428.6		102.2	47.9
Impairment charges	607.2		—		—		607.2	—
(Gain) loss on sale of assets	(1.3)		2.6		(0.6)		3.9	(3.2)
Operating income	$	1,361.4	$	1,914.4	$	1,835.5	(553.0)	78.9
Equity in net earnings from investments	$	143.2	$	154.5	$	158.4	(11.3)	(3.9)
Impairment of equity investments	$	(37.7)	$	—	$	—	37.7	—
Interest expense, net of capitalized interest	$	(712.9)	$	(491.8)	$	(469.6)	221.1	22.2
Net income	$	612.8	$	1,278.6	$	1,155.0	(665.8)	123.6
Diluted EPS	$	1.42	$	3.07	$	2.78	(1.65)	0.29
Adjusted EBITDA	$	2,723.7	$	2,580.2	$	2,447.5	143.5	132.7
Distributable cash flow	$	1,881.6	$	2,016.1	$	1,822.4	(134.5)	193.7
Capital expenditures	$	2,195.4	$	3,848.3	$	2,141.5	(1,652.9)	1,706.8


	Years Ended December 31,
Operating Information (a)	2020		2019		2018
Natural gas gathered (BBtu/d)	2,553		2,753		2,546
Natural gas processed (BBtu/d) (b)	2,364		2,555		2,382


Average fee rate ($/MMBtu)	$	0.89	$	0.92	$	0.90


	Years Ended December 31,
Operating Information	2020		2019		2018

Raw feed throughput (MBbl/d) (a)	1,084		1,079		1,010
Average Conway-to-Mont Belvieu OPIS price differential - ethane in ethane/propane mix ($/gallon)	$	0.01	$	0.07	$	0.15


	Years Ended December 31,
(Unaudited)	2020		2019		2018
Reconciliation of net income to adjusted EBITDA, distributable cash flow and dividend coverage	(Thousands of dollars, except per share amounts and coverage ratios)
Net income	$	612,809	$	1,278,577	$	1,155,032
Add:
Interest expense, net of capitalized interest	712,886		491,773		469,620
Depreciation and amortization	578,662		476,535		428,557
Income tax expense	189,507		372,414		362,903
Impairment charges	644,930		—		—
Noncash compensation expense (a)	8,540		26,699		37,954
Equity AFUDC and other noncash items	(23,661)		(65,811)		(6,545)
Adjusted EBITDA (b)	2,723,673		2,580,187		2,447,521
Interest expense, net of capitalized interest	(712,886)		(491,773)		(469,620)
Maintenance capital	(136,920)		(195,631)		(188,420)
Equity in net earnings from investments	(143,241)		(154,541)		(158,383)
Distributions received from unconsolidated affiliates	176,160		257,644		197,285
Other (b)	(25,195)		20,227		(5,994)
Distributable cash flow	1,881,591		2,016,113		1,822,389
Dividends paid to preferred shareholders	(1,100)		(1,100)		(1,100)
Distributable cash flow to shareholders	1,880,491		2,015,013		1,821,289
Dividends paid	(1,604,266)		(1,456,528)		(1,333,958)
Distributable cash flow in excess of dividends paid	$	276,225	$	558,485	$	487,331
Dividends paid per share	$	3.74	$	3.53	$	3.245
Dividend coverage ratio	1.17		1.38		1.37
Number of shares used in computation (thousands)	428,948		412,614		411,081


Rating Agency	Long-Term Rating	Short-Term Rating	Outlook
Moody’s	Baa3	Prime-3	Stable
S&P	BBB	A-2	Stable
Fitch (a)	BBB	F2	Stable
(a) - Fitch assigned first-time ratings to ONEOK in November 2020.


	Payments Due by Period
Contractual Obligations	Total		2021		2022		2023		2024		2025		Thereafter
	(Millions of dollars)
Senior notes	$	14,347.9	$	—	$	1,437.7	$	925.0	$	500.0	$	887.0	$	10,598.2

Guardian Pipeline senior notes	13.7		7.7		6.0		—		—		—		—
Interest payments on debt	9,710.4		704.2		675.0		631.4		586.8		555.7		6,557.3
Operating leases	116.1		16.5		15.1		13.8		12.5		11.1		47.1
Finance lease	35.1		4.5		4.5		4.5		4.5		4.5		12.6
Firm transportation and storage contracts	516.7		70.9		60.9		55.8		53.4		47.9		227.8
Financial and physical derivatives	393.4		377.9		15.5		—		—		—		—
Employee benefit plans	57.0		11.2		11.8		12.9		10.3		10.8		—
Purchase commitments and other	369.6		83.8		83.4		81.6		41.1		40.7		39.0
Total	$	25,559.9	$	1,276.7	$	2,309.9	$	1,725.0	$	1,208.6	$	1,557.7	$	17,482.0


Commodity Contracts	December 31, 2020		December 31, 2019
	(Millions of dollars)
Crude oil and NGLs	$	20.0	$	26.1
Natural gas	10.6		12.7
Total change in estimated fair value of commodity contracts	$	30.6	$	38.8


	Year Ending December 31, 2021
	Volumes Hedged	Average Price			Percentage Hedged
NGLs - excluding ethane (MBbl/d) - Conway/Mont Belvieu	10.4	$	0.51	/ gallon	60%
Condensate (MBbl/d) - WTI-NYMEX	2.9	$	42.87	/ Bbl	74%
Natural gas (BBtu/d) - NYMEX and basis	118.6	$	2.64	/ MMBtu	75%


	Years Ended December 31,						2020 vs. 2019	2019 vs. 2018
Financial Results	2020		2019		2018		$ Increase (Decrease)
	(Millions of dollars)
NGL sales	$	775.9	$	1,024.3	$	1,567.2	(248.4)	(542.9)
Condensate sales	113.5		200.1		208.8		(86.6)	(8.7)
Residue natural gas sales	771.5		966.1		1,084.2		(194.6)	(118.1)
Gathering, compression, dehydration and processing fees and other revenue	159.2		178.1		174.4		(18.9)	3.7
Cost of sales and fuel (exclusive of depreciation and operating costs)	(844.0)		(1,302.3)		(2,041.4)		(458.3)	(739.1)
Operating costs, excluding noncash compensation adjustments	(320.0)		(352.8)		(357.7)		(32.8)	(4.9)
Equity in net earnings (loss) from investments	(1.1)		(6.3)		0.4		5.2	(6.7)
Other	(5.0)		(4.5)		(4.3)		(0.5)	(0.2)
Adjusted EBITDA	$	650.0	$	702.7	$	631.6	(52.7)	71.1
Impairment charges	$	566.1	$	—	$	—	566.1	—
Capital expenditures	$	446.1	$	926.5	$	694.6	(480.4)	231.9


	December 31, 2020
	Level 1		Level 2		Level 3		Total - Gross		Netting (a)		Total - Net
	(Thousands of dollars)
Derivative assets
Commodity contracts
Financial contracts	$	6,697	$	—	$	103,801	$	110,498	$	(110,498)	$	—


Total derivative assets	$	6,697	$	—	$	103,801	$	110,498	$	(110,498)	$	—

Derivative liabilities
Commodity contracts
Financial contracts	$	(10,489)	$	—	$	(135,122)	$	(145,611)	$	145,611	$	—

Interest-rate contracts	—		(203,407)		—		(203,407)		—		(203,407)
Total derivative liabilities	$	(10,489)	$	(203,407)	$	(135,122)	$	(349,018)	$	145,611	$	(203,407)


	December 31, 2019
	Level 1		Level 2		Level 3		Total - Gross		Netting (a)		Total - Net
	(Thousands of dollars)
Derivative assets
Commodity contracts
Financial contracts	$	10,892	$	—	$	55,557	$	66,449	$	(28,588)	$	37,861

Interest-rate contracts	—		581		—		581		—		581
Total derivative assets	$	10,892	$	581	$	55,557	$	67,030	$	(28,588)	$	38,442

Derivative liabilities
Commodity contracts
Financial contracts	$	(4,811)	$	—	$	(24,785)	$	(29,596)	$	28,588	$	(1,008)

Interest-rate contracts	—		(201,941)		—		(201,941)		—		(201,941)
Total derivative liabilities	$	(4,811)	$	(201,941)	$	(24,785)	$	(231,537)	$	28,588	$	(202,949)


ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF INCOME

	Years Ended December 31,
	2020		2019		2018
	(Thousands of dollars, except per share amounts)
Revenues
Commodity sales	$	7,255,259	$	8,916,047	$	11,395,642
Services	1,286,983		1,248,320		1,197,554
Total revenues (Note P)	8,542,242		10,164,367		12,593,196
Cost of sales and fuel (exclusive of items shown separately below)	5,110,146		6,788,040		9,422,708
Operations and maintenance	761,176		863,708		803,146
Depreciation and amortization	578,662		476,535		428,557
Impairment charges (Note A)	607,200		—		—
General taxes	125,028		119,156		103,922
(Gain) loss on sale of assets	(1,327)		2,575		(601)
Operating income	1,361,357		1,914,353		1,835,464
Equity in net earnings from investments (Note M)	143,241		154,541		158,383
Impairment of equity investments (Note A)	(37,730)		—		—
Allowance for equity funds used during construction	23,662		64,815		7,962
Other income	43,745		27,058		674
Other expense	(19,073)		(18,003)		(14,928)
Interest expense (net of capitalized interest of $75,436, $107,275 and $28,062, respectively)	(712,886)		(491,773)		(469,620)
Income before income taxes	802,316		1,650,991		1,517,935
Income taxes (Note L)	(189,507)		(372,414)		(362,903)
Net income	612,809		1,278,577		1,155,032
Less: Net income attributable to noncontrolling interests	—		—		3,329
Net income attributable to ONEOK	612,809		1,278,577		1,151,703
Less: Preferred stock dividends	1,100		1,100		1,100
Net income available to common shareholders	$	611,709	$	1,277,477	$	1,150,603

Basic EPS (Note I)	$	1.42	$	3.09	$	2.80

Diluted EPS (Note I)	$	1.42	$	3.07	$	2.78
Average shares (thousands)
Basic	431,105		413,560		411,485
Diluted	431,782		415,444		414,195


ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

	Years Ended December 31,
	2020		2019		2018
	(Thousands of dollars)
Net income	$	612,809	$	1,278,577	$	1,155,032
Other comprehensive income (loss), net of tax
Change in fair value of derivatives, net of tax of $49,292, $44,149 and $1,694, respectively	(165,023)		(147,803)		(5,673)
Derivative amounts reclassified to net income, net of tax of $(6,313), $6,058 and $(11,013), respectively	21,097		(21,057)		36,870
Change in retirement and other postretirement benefit plan obligations, net of tax of $7,812, $2,910 and $(1,425), respectively	(26,154)		(9,696)		4,771
Other comprehensive income (loss) of unconsolidated affiliates, net of tax of $2,201, $2,152 and $(724), respectively	(7,369)		(7,205)		2,424
Total other comprehensive income (loss), net of tax	(177,449)		(185,761)		38,392
Comprehensive income	435,360		1,092,816		1,193,424
Less: Comprehensive income attributable to noncontrolling interests	—		—		3,329
Comprehensive income attributable to ONEOK	$	435,360	$	1,092,816	$	1,190,095


ONEOK, Inc. and Subsidiaries
CONSOLIDATED BALANCE SHEETS

	December 31,		December 31,
	2020		2019
Assets	(Thousands of dollars)
Current assets
Cash and cash equivalents	$	524,496	$	20,958
Accounts receivable, net	829,796		835,121
Materials and supplies	143,178		201,749
NGLs and natural gas in storage	227,810		304,926
Commodity imbalances	11,959		25,267
Other current assets	132,536		82,313
Total current assets	1,869,775		1,470,334
Property, plant and equipment
Property, plant and equipment	23,072,935		22,051,492
Accumulated depreciation and amortization	3,918,007		3,702,807
Net property, plant and equipment (Note D)	19,154,928		18,348,685
Investments and other assets
Investments in unconsolidated affiliates (Note M)	805,032		861,844
Goodwill and intangible assets (Note E)	773,723		957,833

Other assets	475,296		173,425
Total investments and other assets	2,054,051		1,993,102
Total assets	$	23,078,754	$	21,812,121


ONEOK, Inc. and Subsidiaries
CONSOLIDATED BALANCE SHEETS
(Continued)
	December 31,		December 31,
	2020		2019
Liabilities and equity	(Thousands of dollars)
Current liabilities
Current maturities of long-term debt (Note F)	$	7,650	$	7,650
Short-term borrowings (Note F)	—		220,000
Accounts payable	719,302		1,209,900
Commodity imbalances	186,372		104,480
Accrued taxes	89,428		75,422
Accrued interest	245,153		190,750
Operating lease liability (Note O)	13,610		1,883
Other current liabilities	83,032		210,213
Total current liabilities	1,344,547		2,020,298
Long-term debt, excluding current maturities (Note F)	14,228,421		12,479,757
Deferred credits and other liabilities
Deferred income taxes (Note L)	669,697		536,063
Operating lease liability (Note O)	87,610		13,509
Other deferred credits	706,081		536,543
Total deferred credits and other liabilities	1,463,388		1,086,115
Commitments and contingencies (Note N)
Equity (Note G)
ONEOK shareholders’ equity:
Preferred stock, $0.01 par value: authorized and issued 20,000 shares at December 31, 2020, and at December 31, 2019	—		—
Common stock, $0.01 par value: authorized 1,200,000,000 shares; issued 474,916,234 shares and outstanding 444,872,383 shares at December 31, 2020; issued 445,016,234 shares and outstanding 413,239,050 shares at December 31, 2019	4,749		4,450
Paid-in capital	7,353,396		7,403,895
Accumulated other comprehensive loss (Note H)	(551,449)		(374,000)
Retained earnings	—		—
Treasury stock, at cost: 30,043,851 shares at December 31, 2020, and 31,777,184 shares at December 31, 2019	(764,298)		(808,394)
Total equity	6,042,398		6,225,951
Total liabilities and equity	$	23,078,754	$	21,812,121


ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF CASH FLOWS
	Years Ended December 31,
	2020		2019		2018
	(Thousands of dollars)
Operating activities
Net income	$	612,809	$	1,278,577	$	1,155,032
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	578,662		476,535		428,557
Impairment charges	644,930		—		—
Equity in net earnings from investments	(143,241)		(154,541)		(158,383)
Distributions received from unconsolidated affiliates	144,352		163,476		170,528
Deferred income tax expense	186,730		372,729		361,010
Other, net	35,327		(26,101)		23,570
Changes in assets and liabilities:
Accounts receivable	(1,297)		(19,688)		383,993
NGLs and natural gas in storage	77,116		(8,259)		38,456
Accounts payable	(80,257)		(62,946)		(320,132)
Commodity imbalances	95,200		(1,934)		(44,302)
Accrued interest	54,403		29,373		26,068
Risk-management assets and liabilities	(187,458)		(86,268)		117,717
Other assets and liabilities, net	(118,208)		(14,174)		4,605
Cash provided by operating activities	1,899,068		1,946,779		2,186,719
Investing activities
Capital expenditures (less allowance for equity funds used during construction)	(2,195,381)		(3,848,349)		(2,141,475)
Distributions received from unconsolidated affiliates in excess of cumulative earnings	31,808		94,168		26,757
Other, net	(106,956)		(14,577)		(170)
Cash used in investing activities	(2,270,529)		(3,768,758)		(2,114,888)
Financing activities
Dividends paid	(1,605,366)		(1,457,628)		(1,335,058)
Distributions to noncontrolling interests	—		—		(3,500)
Borrowing (repayment) of short-term borrowings, net	(220,000)		220,000		(614,673)
Issuance of long-term debt, net of discounts	3,244,777		4,185,435		1,795,773
Debt financing costs	(28,247)		(29,747)		(13,441)
Repayment of long-term debt	(1,457,222)		(1,057,348)		(932,650)
Issuance of common stock	969,759		29,040		1,203,981
Acquisition of noncontrolling interests	—		—		(195,000)
Other, net	(28,702)		(58,790)		(2,481)
Cash provided by (used in) financing activities	874,999		1,830,962		(97,049)
Change in cash and cash equivalents	503,538		8,983		(25,218)
Cash and cash equivalents at beginning of period	20,958		11,975		37,193
Cash and cash equivalents at end of period	$	524,496	$	20,958	$	11,975
Supplemental cash flow information:
Cash paid for interest, net of amounts capitalized	$	760,984	$	435,165	$	418,244
Cash paid for income taxes, net of refunds	$	342	$	2,690	$	2,225


ONEOK, Inc. and Subsidiaries
CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

	ONEOK Shareholders’ Equity
	Common Stock Issued	Preferred Stock Issued	Common Stock		Preferred Stock		Paid-in Capital
	(Shares)		(Thousands of dollars)
January 1, 2018	423,166,234	20,000	$	4,232	$	—	$	6,588,878
Cumulative effect adjustment for adoption of ASUs (a)	—	—	—		—		—
Net income	—	—	—		—		—
Other comprehensive income	—	—	—		—		—

Preferred stock dividends - $55.00 per share (Note G)	—	—	—		—		—
Common stock issued	21,850,000	—	218		—		1,183,321
Common stock dividends - $3.245 per share (Note G)	—	—	—		—		(144,805)
Distributions to noncontrolling interests	—	—	—		—		—
Contributions from noncontrolling interests	—	—	—		—		—
Acquisition of noncontrolling interests (Note G)	—	—	—		—		(21,220)
Other, net	—	—	—		—		8,964
December 31, 2018	445,016,234	20,000	4,450		—		7,615,138
Cumulative effect adjustment for adoption of ASU 2016-02, “Leases (Topic 842)”	—	—	—		—		—
Net income	—	—	—		—		—
Other comprehensive loss (Note H)	—	—	—		—		—
Preferred stock dividends - $55.00 per share (Note G)	—	—	—		—		—
Common stock issued	—	—	—		—		(7,667)
Common stock dividends - $3.53 per share (Note G)	—	—	—		—		(180,421)



Other, net	—	—	—		—		(23,155)
December 31, 2019	445,016,234	20,000	4,450		—		7,403,895

Net income	—	—	—		—		—
Other comprehensive loss (Note H)	—	—	—		—		—
Preferred stock dividends - $55.00 per share (Note G)	—	—	—		—		(550)
Common stock issued	29,900,000	—	299		—		934,473
Common stock dividends - $3.74 per share (Note G)	—	—	—		—		(992,741)
Other, net	—	—	—		—		8,319
December 31, 2020	474,916,234	20,000	$	4,749	$	—	$	7,353,396


	Years Ended
	December 31,
Derivative Assets (Liabilities)	2020		2019
	(Thousands of dollars)
Net assets at beginning of period	$	30,772	$	40,484
Total changes in fair value:

Settlements included in net income (a)	(31,660)		(40,344)
New Level 3 derivatives included in other comprehensive loss (b)	(36,568)		30,627
Unrealized change included in other comprehensive loss (b)	6,135		5

Net assets (liabilities) at end of period	$	(31,321)	$	30,772


		December 31, 2020				December 31, 2019
	Location in our Consolidated Balance Sheets	Assets		(Liabilities)		Assets		(Liabilities)
		(Thousands of dollars)
Derivatives designated as hedging instruments
Commodity contracts (a)
Financial contracts (b)	Other current assets	$	107,461	$	(142,573)	$	64,858	$	(26,997)
	Other deferred credits	—		—		1,591		(2,599)


Interest-rate contracts	Other current liabilities	—		—		—		(90,161)
	Other assets/other deferred credits	—		(203,407)		581		(111,780)
Total derivatives designated as hedging instruments		107,461		(345,980)		67,030		(231,537)
Derivatives not designated as hedging instruments
Commodity contracts (a)
Financial contracts (b)		3,037		(3,038)		—		—
Total derivatives not designated as hedging instruments		3,037		(3,038)		—		—
Total derivatives		$	110,498	$	(349,018)	$	67,030	$	(231,537)


Derivatives in Cash Flow Hedging Relationships	Location of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Net Income
		Years Ended December 31,
		2020		2019		2018
		(Thousands of dollars)
Commodity contracts	Commodity sales revenues	$	85,436	$	94,547	$	(37,596)
	Cost of sales and fuel	(19,170)		(44,202)		8,000
Interest-rate contracts (a)	Interest expense	(93,676)		(23,230)		(18,287)
Total change in fair value of cash flow hedges reclassified from accumulated other comprehensive loss into net income on derivatives		$	(27,410)	$	27,115	$	(47,883)


	Estimated Useful Lives (Years)	December 31, 2020		December 31, 2019
		(Thousands of dollars)
Nonregulated
Gathering pipelines and related equipment	5 to 40	$	4,143,752	$	4,316,936
Processing and fractionation and related equipment	3 to 40	5,084,802		4,439,332
Storage and related equipment	3 to 54	798,785		684,635
Transmission pipelines and related equipment	5 to 54	810,434		797,678
General plant and other	2 to 60	647,675		610,013
Construction work in process	—	1,265,736		1,645,663
Regulated
Storage and related equipment	5 to 25	9,180		9,180
Natural gas transmission pipelines and related equipment	5 to 77	1,569,268		1,552,546
NGL transmission pipelines and related equipment	5 to 88	8,423,544		6,126,056
General plant and other	2 to 50	72,535		66,507
Construction work in process	—	247,224		1,802,946
Property, plant and equipment		23,072,935		22,051,492
Accumulated depreciation and amortization - nonregulated		(2,514,328)		(2,471,649)
Accumulated depreciation and amortization - regulated		(1,403,679)		(1,231,158)
Net property, plant and equipment		$	19,154,928	$	18,348,685


	Senior Unsecured Obligations		Guardian Pipeline		Total
	(Millions of dollars)
2021	$	—	$	7.7	$	7.7
2022	$	1,437.7	$	6.0	$	1,443.7
2023	$	925.0	$	—	$	925.0
2024	$	500.0	$	—	$	500.0
2025	$	887.0	$	—	$	887.0


	Risk- Management Assets/Liabilities (a)		Retirement and Other Postretirement Benefit Plan Obligations (a) (b)		Risk- Management Assets/Liabilities of Unconsolidated Affiliates (a)		Accumulated Other Comprehensive Loss (a)
	(Thousands of dollars)
January 1, 2019	$	(64,660)	$	(121,785)	$	(1,794)	$	(188,239)
Other comprehensive loss before reclassifications	(147,803)		(19,490)		(7,275)		(174,568)
Amounts reclassified to net income (c)	(21,057)		9,794		70		(11,193)
Other comprehensive loss	(168,860)		(9,696)		(7,205)		(185,761)
December 31, 2019	(233,520)		(131,481)		(8,999)		(374,000)
Other comprehensive loss before reclassifications	(165,023)		(40,341)		(8,635)		(213,999)
Amounts reclassified to net income (c)	21,097		14,187		1,266		36,550
Other comprehensive loss	(143,926)		(26,154)		(7,369)		(177,449)
December 31, 2020	$	(377,446)	$	(157,635)	$	(16,368)	$	(551,449)


	Risk- Management Assets/Liabilities (a)
	(Thousands of dollars)
Commodity derivative instruments expected to be realized within the next 24 months (b)	$	(27,303)
Settled interest-rate swaps to be recognized over the life of the long-term, fixed-rate debt (c)	(193,519)
Interest-rate swaps with future settlement dates expected to be amortized over the life of long-term debt	(156,624)
Accumulated other comprehensive loss at December 31, 2020	$	(377,446)


	Year Ended December 31, 2020
	Income		Shares	Per Share Amount
	(Thousands, except per share amounts)
Basic EPS
Net income available for common stock	$	611,709	431,105	$	1.42
Diluted EPS
Effect of dilutive securities	—		677
Net income available for common stock and common stock equivalents	$	611,709	431,782	$	1.42


	Year Ended December 31, 2019
	Income		Shares	Per Share Amount
	(Thousands, except per share amounts)
Basic EPS
Net income available for common stock	$	1,277,477	413,560	$	3.09
Diluted EPS
Effect of dilutive securities	—		1,884
Net income available for common stock and common stock equivalents	$	1,277,477	415,444	$	3.07


	Year Ended December 31, 2018
	Income		Shares	Per Share Amount
	(Thousands, except per share amounts)
Basic EPS
Net income attributable to ONEOK available for common stock	$	1,150,603	411,485	$	2.80
Diluted EPS
Effect of dilutive securities	—		2,710
Net income attributable to ONEOK available for common stock and common stock equivalents	$	1,150,603	414,195	$	2.78


	Number of Units	Weighted Average Price
Nonvested December 31, 2019	698,990	$	54.05
Granted	216,392	$	76.49
Released to participants	(240,576)	$	46.58
Forfeited	(28,519)	$	65.20
Nonvested December 31, 2020	646,287	$	63.85


	Retirement Benefits				Other Postretirement Benefits
	December 31,				December 31,
	2020		2019		2020		2019
Change in benefit obligation	(Thousands of dollars)
Benefit obligation, beginning of period	$	534,849	$	466,994	$	52,309	$	46,840
Service cost	8,154		7,825		460		468
Interest cost	18,318		20,528		1,771		2,038
Plan participants’ contributions	—		—		1,032		1,142
Actuarial loss	37,951		55,954		2,860		5,101
Benefits paid	(16,200)		(16,452)		(3,917)		(3,280)
Benefit obligation, end of period	583,072		534,849		54,515		52,309

Change in plan assets
Fair value of plan assets, beginning of period	346,792		290,684		39,060		30,800
Actual return on plan assets (a)	36,400		58,060		(15,699)		8,087
Employer contributions	12,100		14,500		—		2,000
Plan participants’ contributions	—		—		1,032		1,142
Benefits paid	(16,200)		(16,452)		(3,519)		(2,969)
Fair value of plan assets, end of period	379,092		346,792		20,874		39,060
Balance at December 31	$	(203,980)	$	(188,057)	$	(33,641)	$	(13,249)

Current liabilities	$	(4,679)	$	(4,616)	$	—	$	—
Noncurrent liabilities	(199,301)		(183,441)		(33,641)		(13,249)
Balance at December 31	$	(203,980)	$	(188,057)	$	(33,641)	$	(13,249)


	2020	2019
Health care cost-trend rate assumed for next year	6.50%	7.00%
Rate to which the cost-trend rate is assumed to decline (the ultimate trend rate)	5.00%	5.00%
Year that the rate reaches the ultimate trend rate	2024	2024


Domestic and international equities	42	%
Long duration fixed income	30	%
Return-seeking credit	11	%
Hedge funds	10	%
Real estate funds	7	%
Total	100	%