Select Water Solutions, Inc.

Disclosure Controls and Procedures

We maintain disclosure controls and procedures that are designed to provide reasonable assurance that the information required to be disclosed by us in our reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to our management, including our principal executive officer and principal financial officer, as appropriate, to allow timely decisions regarding required disclosure.

As required by Rule 13a-15(b) under the Exchange Act, we have evaluated, under the supervision and with the participation of management, including our principal executive officer and principal financial officer, the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this Quarterly Report. Based upon that evaluation, our principal executive officer and principal financial officer concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of March 31, 2025.

Changes in Internal Control over Financial Reporting

In February 2025, the Company completed the implementation of its new enterprise resource planning (“ERP”) software system and modified certain existing internal control processes and procedures related to the new system. These changes did not materially affect our internal control over financial reporting. As the Company implements new functionality under this ERP system, the Company will continue to assess the impact on its internal control over financial reporting. Other than described pursuant to the foregoing, there were no changes in the Company's internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the quarter ended March 31, 2025 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.