EX-21 3 fs42023ex21_oneokinc.htm LIST OF SUBSIDIARIES OF ONEOK, INC

Exhibit 21

ONEOK, Inc.

SUBSIDIARIES OF THE COMPANY

AS OF JUNE 20, 2023

Subsidiaries |  | State of Incorporation or Organization
Bighorn Gas Gathering, L.L.C. (49.0%) |  | Delaware
Bison Prairie Assurance, L.L.C. |  | Oklahoma
Black Mesa Holdings, Inc. |  | Delaware
Black Mesa Pipeline, Inc. |  | Delaware
Black Mesa Pipeline Operations, L.L.C. |  | Delaware
Black Mesa Technologies, Inc. |  | Oklahoma
Border Midwestern Company |  | Delaware
Chisholm Pipeline Company (50%) |  | Delaware
Chisholm Pipeline Holdings, L.L.C. |  | Delaware
Crestone Energy Ventures, L.L.C. |  | Delaware
Crestone Gathering Services, L.L.C. |  | Delaware
Crestone Powder River, L.L.C. |  | Delaware
Crestone Wind River, L.L.C. |  | Delaware
Fort Union Gas Gathering, L.L.C. (50%) |  | Delaware
Guardian Pipeline, L.L.C. |  | Delaware
Heartland Pipeline Company (general partnership) (50%) |  | Texas
Lost Creek Gathering Company, L.L.C. (35%) |  | Delaware
Mid Continent Market Center, L.L.C. |  | Kansas
Midwestern Gas Transmission Company |  | Delaware
Mont Belvieu I Fractionation Facility (joint venture) (80%) |  | Texas
Northern Border Pipeline Company (general partnership) (50%) |  | Texas
OkTex Pipeline Company, L.L.C. |  | Delaware
ONEOK Arbuckle II Pipeline, L.L.C. |  | Oklahoma
ONEOK Arbuckle North Pipeline, L.L.C. |  | Delaware
ONEOK Arbuckle Pipeline, L.L.C. |  | Delaware
ONEOK Bakken Pipeline, L.L.C. |  | Delaware
ONEOK Bushton Processing, L.L.C. |  | Delaware
ONEOK Elk Creek Pipeline, L.L.C. |  | Oklahoma
ONEOK Energy Services Company, II |  | Delaware
ONEOK Energy Services Company, L.P. |  | Texas
ONEOK Energy Services Holdings, L.L.C. |  | Oklahoma
ONEOK Field Services Company, L.L.C. |  | Oklahoma
ONEOK Gas Storage Holdings, L.L.C. |  | Delaware
ONEOK Gas Storage, L.L.C. |  | Oklahoma
ONEOK Gas Transportation, L.L.C. |  | Oklahoma
ONEOK Hydrocarbon GP, L.L.C. |  | Delaware
ONEOK Hydrocarbon Holdings, L.L.C. |  | Delaware
ONEOK Hydrocarbon Southwest, L.L.C. |  | Delaware
ONEOK Hydrocarbon, L.L.C. |  | Delaware
ONEOK Hydrocarbon, L.P. |  | Delaware
ONEOK ILP GP, L.L.C. |  | Delaware
ONEOK Leasing Company |  | Delaware
ONEOK MB I, L.P. |  | Delaware

Subsidiaries |  | State of Incorporation or Organization
ONEOK Midstream Gas Supply, L.L.C. |  | Oklahoma
ONEOK Mont Belvieu Properties, L.L.C. |  | Delaware
ONEOK Mont Belvieu Storage Company, L.L.C. |  | Delaware
ONEOK NGL Gathering, L.L.C. |  | Delaware
ONEOK NGL Pipeline, L.L.C. |  | Delaware
ONEOK North System, L.L.C. |  | Delaware
ONEOK Northern Border Pipeline Company Holdings, L.L.C. |  | Oklahoma
ONEOK Overland Pass Holdings, L.L.C. |  | Oklahoma
ONEOK Parking Company, L.L.C. |  | Delaware
ONEOK Partners GP, L.L.C. |  | Delaware
ONEOK Partners Intermediate Limited Partnership |  | Delaware
ONEOK Partners, L.P. |  | Delaware
ONEOK Permian NGL Operating Company, L.L.C. |  | Delaware
ONEOK Pipeline Holdings, L.L.C. |  | Delaware
ONEOK Rockies Investments, L.L.C. |  | Delaware
ONEOK Rockies Midstream, L.L.C. |  | Delaware
ONEOK Services Company, L.L.C. |  | Oklahoma
ONEOK Southeast Texas NGL Pipeline, L.L.C. |  | Oklahoma
ONEOK Sterling III Pipeline, L.L.C. |  | Oklahoma
ONEOK Texas Gas Storage, L.L.C. |  | Texas
ONEOK Underground Storage Company, L.L.C. |  | Kansas
ONEOK Unit Holdings, Inc. |  | Delaware
ONEOK Ventures, L.L.C. |  | Oklahoma
ONEOK Ventures Direct Investments, L.L.C. |  | Oklahoma
ONEOK Ventures Fund Investments, L.L.C. |  | Oklahoma
ONEOK VESCO Holdings, L.L.C. |  | Delaware
ONEOK West Texas NGL Pipeline, L.L.C. |  | Texas
ONEOK Western Trail Pipeline, L.L.C. |  | Oklahoma
ONEOK WesTex Transmission, L.L.C. |  | Delaware
Otter Merger Sub, LLC |  | Delaware
Overland Pass Pipeline Company LLC (50%) |  | Delaware
Roadrunner Gas Transmission Holdings, LLC (50%) |  | Delaware
Roadrunner Gas Transmission, LLC (100% owned by Roadrunner Gas Transmission Holdings, LLC) |  | Delaware
Saguaro Connector Pipeline, L.L.C. |  | Delaware
Saguaro Connector Pipeline Holdings, L.L.C. |  | Delaware
TXGC Pipelines, L.L.C. |  | Delaware
TXGC Properties, L.L.C. |  | Delaware
Venice Energy Services Company, L.L.C. (10.1765%) |  | Delaware
Viking Gas Transmission Company |  | Delaware