S&T BANCORP INC

a) Evaluation of Disclosure Controls and Procedures

Under the supervision and with the participation of S&T’s Chief Executive Officer, or CEO, and Chief Financial Officer, or CFO (its principal executive officer and principal financial officer), management has evaluated the effectiveness of the design and operation of S&T’s disclosure controls and procedures as of December 31, 2023. In designing and evaluating the disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives.

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed by us in the reports that we file or submit under the Securities Exchange Act of 1934, as amended, or the Exchange Act, is recorded, processed, summarized and reported within the time periods required by the Securities and Exchange Commission, or the SEC, and that such information is accumulated and communicated to S&T’s management, including our CEO and CFO, as appropriate, to allow timely decisions regarding required disclosure.

Based on and as of the date of such evaluation, our CEO and CFO concluded that the design and operation of our disclosure controls and procedures were effective in all material respects, as of the end of the period covered by this Report.

b) Management’s Report on Internal Control over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rule 13a-15(f). Management assessed S&T’s system of internal control over financial reporting as of December 31, 2023, in relation to criteria for effective internal control over financial reporting as described in “Internal Control Integrated Framework (2013),” issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in 2013. Based on this assessment, management concludes that, as of December 31, 2023, S&T’s system of internal control over financial reporting is effective and meets the criteria of the “Internal Control Integrated Framework (2013).”

Management assessed the effectiveness of S&T's internal control over financial reporting as of December 31, 2023, in relation to criteria for effective internal control over financial reporting as described in Internal Control - Integrated Framework, issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework). Based on this assessment, management concluded that, as of December 31, 2023, S&T's internal controls over financial reporting were effective. Our independent registered public accounting firm, has issued a report on the effectiveness of S&T’s internal control over financial reporting as of December 31, 2023, which is included herein.

c) Changes in Internal Control Over Financial Reporting

No changes were made to S&T’s internal control over financial reporting (as defined in Rule 13a-15(f) under the Exchange Act) during the last fiscal quarter that materially affected, or are reasonably likely to materially affect, S&T’s internal control over financial reporting.