Document

Exhibit 22.1

List of Subsidiary Guarantors and Issuers

of Guaranteed Securities

As of March 31, 2025, the following entities guarantee the notes issued by ONEOK, Inc. (the "ONEOK Notes"), ONEOK Partners, L.P. (the "ONEOK Partners Notes"), EnLink Midstream, LLC (n/k/a Elk Merger Sub II, L.L.C.) (the "Legacy EnLink Notes") and EnLink Midstream Partners, L.P. (the "Legacy EnLink Partners Notes").

Entity

Jurisdiction of
Incorporation or Organization

ONEOK Notes

ONEOK Partners Notes

Legacy EnLink Notes

Legacy EnLink Partners Notes

ONEOK, Inc.

Oklahoma

Issuer

Guarantor

Obligor (b)

ONEOK Partners, L.P.

Delaware

Guarantor

Issuer

Guarantor

ONEOK Partners Intermediate Limited Partnership

Delaware

Guarantor

Magellan Midstream Partners, L.P.

Delaware

Guarantor

EnLink Midstream, LLC (n/k/a Elk Merger Sub II, L.L.C.) (a)

Delaware

Guarantor

Issuer/ Guarantor

Guarantor

EnLink Midstream Partners, L.P.

Delaware

Guarantor

Issuer/ Guarantor

(a) On January 31, 2025, EnLink Midstream, LLC merged with and into Elk Merger Sub II, L.L.C., with Elk Merger Sub II, L.L.C. surviving (the “Merger”). In connection with the Merger, Elk Merger Sub II, L.L.C. assumed the obligations under the Legacy EnLink Notes and EnLink Midstream, LLC was released from its obligations.

(b) On January 31, 2025, following the Merger, ONEOK, Inc. assumed the obligations under the Legacy EnLink Notes and the Legacy EnLink Partners Notes, and Elk Merger Sub II, L.L.C. and EnLink Midstream Partners, L.P. was each released from its obligations under and provided a guarantee of the Legacy EnLink Notes and Legacy EnLink Partners Notes, as applicable. Elk Merger Sub II, L.L.C. and EnLink Midstream Partners, L.P. also provided a guarantee of the ONEOK Notes and ONEOK Partners Notes.

As of March 31, 2025, the ONEOK Notes consisted of the following securities:


Issued under the Indenture dated as of September 24, 1998
6-7/8% Debentures due 2028
Issued under the Indenture dated as of December 28, 2001
6.00% Notes due 2035
Issued under the Indenture dated as of April 19, 2007
6.40% Senior Notes due 2037
Issued under the Indenture dated as of August 11, 2010
5.00% Senior Notes due 2026
3.25% Senior Notes due 2030
4.20% Senior Notes due 2042
5.15% Senior Notes due 2043
4.20% Senior Notes due 2045
4.25% Senior Notes due 2046
4.20% Senior Notes due 2047
4.85% Senior Notes due 2049
3.95% Senior Notes due 2050
Issued under the Indenture dated as of January 26, 2012
2.200% Notes due 2025
5.550% Notes due 2026
5.850% Notes due 2026
4.000% Notes due 2027
4.25% Notes due 2027
4.55% Notes due 2028
5.650% Notes due 2028
4.35% Notes due 2029
3.40% Notes due 2029
4.40% Notes due 2029
3.100% Notes due 2030
5.800% Notes due 2030
6.350% Notes due 2031

Exhibit 22.1


4.75% Notes due 2031
6.10% Notes due 2032
6.050% Notes due 2033
5.05% Notes due 2034
4.950% Notes due 2047
5.20% Notes due 2048
4.45% Notes due 2049
4.500% Notes due 2050
7.150% Notes due 2051
6.625% Notes due 2053
5.70% Notes due 2054
5.85% Notes due 2064

As of March 31, 2025, the ONEOK Partners Notes consisted of the following securities:


Issued under the Indenture dated as of September 25, 2006
6.65% Senior Notes due 2036
6.85% Senior Notes due 2037
6.125% Senior Notes due 2041
6.200% Senior Notes due 2043

As of March 31, 2025, the Legacy EnLink Notes consisted of the following securities:


Issued under the Indenture dated as of April 9, 2019
5.375% Senior Notes due 2029


Issued under the Indenture dated as of December 17, 2020
5.625% Senior Notes 2028


Issued under the Indenture dated as of August 31, 2022
6.5% Senior Notes due 2030


Issued under the Indenture dated as of August 15, 2024
5.65% Senior Notes due 2034

As of March 31, 2025, the Legacy EnLink Partners Notes consisted of the following securities:


Issued under the Indenture dated as of March 19, 2014
4.15% Senior Notes due 2025
4.85% Senior Notes due 2026
5.6% Senior Notes due 2044
5.05% Senior Notes due 2045
5.45% Senior Notes due 2047