Contract

1 ONEOK, INC. EQUITY INCENTIVE PLAN PERFORMANCE UNIT AWARD AGREEMENT This Performance Unit Award Agreement (the “Agreement”) is entered into as of the __ day of _______, 2023, by and between ONEOK, Inc. (the “Company”) and (the “Grantee”), an employee of the Company or a Subsidiary thereof and participant in the ONEOK, Inc. Equity Incentive Plan (the “Plan”), pursuant to the terms of the Plan. 1. Performance Unit Award. This Agreement and the Notice of Performance Unit Award and Agreement dated February 22, 2023, a copy of which is attached hereto and incorporated herein by reference, establishes the terms and conditions for the Company’s grant of an Award of Performance Units (the “Award”) to the Grantee pursuant to the Plan. This Agreement, when executed by the Grantee, constitutes an agreement between the Company and the Grantee. Capitalized terms not defined in this Agreement shall have the meaning ascribed to them in the Plan. 2. Performance Period; Vesting. The Performance Units granted pursuant to the Award will vest in accordance with the following terms and conditions: (a) Grantee’s rights with respect to the Performance Units shall be restricted during the period beginning February 22, 2023 (the “Grant Date”) and ending on February 22, 2026 (the “Performance Period”). The Performance Units shall vest at the end of the Performance Period, subject to continued employment through the end of the Performance Period and achievement of the performance metric described in Section 2(b), except as provided in Section 2(d) or 2(e), as applicable. (b) Except as otherwise provided in this Agreement or the Plan, the Grantee shall vest in a percentage of the number of Performance Units granted by this Award (including any Dividend Equivalents, as described below), if any, at the end of the Performance Period, as provided for in Exhibit A and Exhibit B attached hereto, based upon the Company’s ranking for total shareholder return as compared to the ONEOK Peer Group listed in Exhibit C attached hereto, all as determined by the Committee in its sole discretion. Upon vesting, the Grantee shall become entitled to receive one (1) share of the Company’s common stock (“Common Stock”) for each such Performance Unit, which shall be distributed in accordance with Section 5. No fractional shares shall be issued, and any amount attributable to a fractional share shall instead be withheld to satisfy any withholding tax obligation. (c) If the Grantee’s employment with the Company terminates prior to the end of the Performance Period, other than by reason of (i) Retirement, (ii) Disability, (iii) death or (iv) termination of employment by the Company or a Subsidiary without Cause or by the Grantee for Good Reason upon or within two years following a Change in Control, the Grantee shall forfeit all right, title and interest in the Performance Units and any Common Stock otherwise payable pursuant to this Agreement. For purposes of this Agreement, employment with any Subsidiary of the Company shall be treated as employment with the Company. Likewise, a termination of employment shall not be deemed to occur by reason of a transfer of employment between the Company and any Subsidiary. Exhibit 10.16

2 (d) If the Grantee’s employment with the Company and its Subsidiaries is terminated during the Performance Period, other than upon or during the two years following a Change in Control, by reason of (i) Retirement, (ii) Disability or (iii) death, then the Grantee shall remain eligible to receive a prorated amount of the Performance Units following the end of the Performance Period, based on achievement of the performance metric described in Section 2(b). Such prorated amount of Performance Units shall equal the number of Performance Units that would have vested in accordance with Section 2(b) had the Grantee remained employed through the end of the Performance Period, prorated based on the period of time that the Grantee was employed during the Performance Period, as determined by the Committee in its discretion. Notwithstanding the foregoing, if a Change in Control occurs after the date of the Grantee’s termination of employment as described in this Section 2(d) and prior to payment, the amount of Performance Units that vest shall be calculated pursuant to Section 2(f). Payment shall be made as described in Section 5 below. (e) If the Grantee’s employment with the Company and its Subsidiaries is terminated by the Company or a Subsidiary without Cause, by the Grantee for Good Reason, or on account of Retirement, Disability, or death, in each case upon or within two years following a Change in Control, the Performance Units shall vest in the amount calculated pursuant to Section 2(f). Payment shall be made as described in Section 5 below. (f) Unless the Committee provides otherwise prior to a Change in Control, in the event of a Change in Control during the Performance Period, the amount to be paid with respect to the Performance Units, shall be determined based on the greater of (i) the target number of Performance Units (i.e., applying the 100% Performance Multiplier described in Exhibit A) granted for the Performance Period (prorated for a Grantee whose employment terminates before the end of the Performance Period as described in Section 2(d) or 2(e), based on the period of time that the Grantee was employed during the Performance Period, as determined by the Committee in its discretion) or (ii) the number of Performance Units earned for the Performance Period based upon the actual performance level attained as of the date of the Change in Control, as determined by the Committee in its discretion, in each case, after giving effect to the accumulation of Dividend Equivalents. (g) For purposes of the Award and this Agreement: i. “Retirement” shall mean a voluntary termination of employment if the Grantee has both completed five (5) years of service with the Company and attained age fifty (50). “Years of service” for this purpose excludes any service with any predecessor employer that was not considered within the controlled group (determined in accordance with Code section 414(c)) of the Company as of the Grant Date), unless explicitly required by the agreement executed in connection with such asset or stock acquisition, merger or other similar transaction and “voluntary termination” shall mean that the Grantee had an opportunity to continue employment with the Company, but did not do so. ii. “Disability” shall have the meaning provided in the Plan.

7 Agreement supersedes any prior agreements or understandings, and there are no other agreements or understandings relating to its subject matter. The invalidity or unenforceability of any provision of the Plan or this Agreement shall not affect any other provision of the Plan or this Agreement, and each provision of the Plan and this Agreement shall be severable and enforceable to the extent permitted by law. Should there be any inconsistency between the provisions of this Agreement and the terms of the Award as stated in the resolutions and records of the Board of Directors or the Plan, the provisions of such resolutions and records of the Board of Directors and the Plan shall control. 15. Successors and Assigns. The Award evidenced by this Agreement shall inure to the benefit of and be binding upon the heirs, legatees, legal representatives, successors, and assigns of the parties hereto. 16. Governing Law; Mandatory Claims Procedures. This Agreement shall be construed in accordance with, and subject to, the laws of the State of Oklahoma applicable to contracts made and to be entirely performed in Oklahoma and wholly disregarding any choice of law provisions or conflict of law principles that might otherwise be contrary to this express intent. If Grantee or any person acting on the Grantee’s behalf (the “Claimant”) has any claim or dispute related in any way to the Award or to the Plan, the Claimant must follow the claims and arbitration procedures set forth in Article 13 of the Plan. All claims must be brought no later than one year following the date on which the facts forming the basis of the claim are known or should have been known by the claimant, whichever is earlier. Any claim that is not submitted within the applicable time limit shall be waived. The Grantee hereby acknowledges receipt of this Agreement, the Notice of Performance Unit Award and Agreement and a copy of the Plan, and accepts the Award under the terms and conditions stated in this Agreement, subject to all terms and provisions of the Plan, by signing this Agreement as of the date indicated. In the absence of a signed acceptance, the Grantee will be deemed to have accepted this Award on the Grant Date, and all its associated terms and conditions, including the mandatory claims and arbitration procedures, unless the Grantee notifies the Company of the Grantee’s non-acceptance of the Award by contacting the stock plan administrator, in writing within sixty (60) days of the Grant Date. Date Grantee

8 Exhibit A Performance Unit Criteria 2023-2026 Performance Period ONEOK Total Shareholder Return (TSR) Ranking vs. ONEOK Peer Group Percentage of Performance Units Earned (Performance Multiplier) 90th percentile and above 75th percentile 50th percentile 25th percentile Below 25th percentile 200% 150% 100% 50% 0% If ONEOK’s TSR ranking within the ONEOK Peer Group at the end of the Performance Period is between any two of the stated percentile levels in the above table, the percentage of the Performance Units earned (the performance multiplier) will be interpolated between the earning levels. No Performance Units are earned based on performance if XXXXX’s TSR ranking at the end of the Performance Period is below the 25th percentile within its Peer Group. In no event may the maximum number of Performance Units that may be payable pursuant to this Agreement Agreement (excluding any accumulated Dividend Equivalents).exceed 200% of the target number of Performance Units granted in Section 1 of the Agreement.

9 Exhibit B Illustration of Hypothetical 2023-2026 Performance Period Performance Unit Award Calculation The illustrations below assume that 500 Performance Units are awarded to Grantee in February 2023. ONEOK Total Shareholder Return (TSR) Ranking vs. ONEOK Peer Group Hypothetical 1: If ONEOK’s TSR Ranking for 2023-2026 is at the 40th percentile within the ONEOK Peer Group, then the performance multiplier would be 80 percent, as interpolated between a 50 percent multiplier (25th percentile within Peer Group) and a 100 percent multiplier (50th percentile within Peer Group) from Exhibit A. Hypothetical 2: If ONEOK’s TSR Ranking for 2023-2026 is at the 60th percentile within the ONEOK Peer Group, then the performance multiplier would be 120 percent, as interpolated between a 100 percent multiplier (50th percentile within Peer Group) and a 150 percent multiplier (75th percentile within Peer Group) from Exhibit A. Percentage of Performance Units Earned Hypothetical 1: 80% x 500 PUs = 400 shares of Common Stock payable to Grantee in 2026. Hypothetical 2: 120% x 500 PUs = 600 shares of Common Stock payable to Grantee in 2026.

10 Exhibit C 2023-2026 ONEOK TSR Peer Group* Company Name Sym DCP Midstream LP DCP Energy Transfer LP ET EnLink Midstream, LLC ENLC Enterprise Products Partners EPD Xxxxxx Xxxxxx Inc. KMI Magellan Midstream Partners MMP MPLX LP MPLX NuStar Energy LP NS Plains All American Pipeline LP PAA Targa Resources Corp TRGP Xxxxxxxx Companies Inc. WMB Western Midstream Partners, LP WES * In the event that any member of the 2023-2026 ONEOK Peer Group liquidates or reorganizes under the United States Bankruptcy Code (U.S.C. Title 11) such entity shall remain in the 2023-2026 ONEOK Peer Group but shall be deemed to have a TSR of -100% for purposes of calculating the Performance Multiplier. If any member of the 2023-2026 ONEOK Peer Group is acquired by an unrelated entity before the end of the Performance Period, such member shall be removed from the 2023-2026 ONEOK Peer Group for purposes of calculating the Performance Multiplier. In all other cases involving merger, reorganization or other material change in ownership, legal structure or business operations of any member of the 2023-2026 ONEOK Peer Group, including acquisition by a related entity before the end of the Performance Period, the Committee shall have discretionary authority to retain, remove or replace such member for purposes of calculating the Performance Multiplier.

11 Exhibit D Beneficiary Designation Form I, _________________________________ (“Grantee”), state that I am a participant in the ONEOK, Inc. Equity Incentive Plan, the ONEOK, Inc. Equity Compensation Plan, or any other stock compensation plan sponsored by ONEOK, Inc. (individually and collectively, the “Plan”), and the holder of one or more Awards granted to me under the Plan. With the understanding that I may change the following beneficiary designations at any time by furnishing written notice thereof to ONEOK, Inc.’s stock plan administrator (provided that such change does not affect the time and form of payment of any amounts subject to an existing deferral election), I hereby designate the following individuals (or entities) as my beneficiaries to receive any and all benefits payable to me under the Plan and to exercise all rights, benefits and features of the Awards described below, in accordance with the terms of the Plan and any associated award agreement, in the event of my death as follows: 1. Primary Beneficiary (Beneficiaries) The Primary Beneficiaries named below shall have first priority to any and all Awards described below and to exercise all rights, benefits and features of the Awards described below, in accordance with the terms of the Plan and any associated award agreement, in the event of my death. Name Relationship Percentage of Total If a designated Primary Beneficiary named dies or ceases to exist prior to receiving the share designated for such Primary Beneficiary, such share shall be transferred proportionately to other surviving and existing designated Primary Beneficiaries. 2. Contingent Beneficiary (or Beneficiaries) The Contingent Beneficiaries named below, if any, shall receive all Awards described below and to exercise, enjoy and receive all rights, benefits and features of the Awards described below (including Awards that I have elected to defer under the Plan or the ONEOK, Inc. 2005 Nonqualified Deferred Compensation Plan, if applicable) in accordance with the Plan and the terms and provisions of such Awards in the event of my death if no Primary Beneficiary named above survives me or exists.