Form: 10-K

Annual report pursuant to Section 13 and 15(d)

February 23, 2022

Exhibit 21.1

Subsidiaries of Select Energy Services, Inc.

Entity

    

State of Formation

Select Agua Libre Midstream, LLC

​

Delaware

Complete Energy Services, LLC

​

Delaware

SES Holdings, LLC

 

Delaware

Select Energy Services, LLC

 

Delaware

Peak Oilfield Services, LLC

 

Texas

Rockwater Energy Solutions, LLC

 

Delaware

Tidal Logistics, Inc.

​

Texas

​