To my fellow shareholders:   In 2022, S&T Bancorp, Inc. reached two major milestones.From recordfinancial performance, to award-winning employee engagement and customer service, to excellent progress on many important initiatives, we have many things to celebrate as we look back on 2023. Our people-forward purpose has been at the core of our success for more than 120 years. We achievedbuilt upon our purpose by introducing Our Shared Future – a strategic framework to defineour values and drivers for profitable growth and create a roadmap that guides our proactive steps to deliver long-term, sustainable financial performance. That strategic framework supported a second consecutive year of record financial performance and celebrated our 120th anniversary. These accomplishments areresults, even during a direct resulttime of S&T’s “People-Forward” culture and a strong foundationhistorically challenging conditions for growth. While we benefited from the interest rate environment and the strategic decisions that we made over the years relative to our balance sheet composition, we also managed credit risk, controlled expenses and—as evidenced by numerous outside awards and recognition—did an excellent job of delighting our customers and engaging with our employees.banking industry.

It’s all about peoplePerformance Drivers

Our work during 2022 extendsunwavering focus on our deep historyfour performance drivers – deposit franchise, core profitability, asset quality, and talent and engagement – continues to help us successfully navigate the ever-changing economic environment and achieve our goals. In 2023, we made substantial progress to improve asset quality and core profitability. Additionally, we initiated infrastructure changes to grow our deposit franchise by expanding our capabilities and teams to ensure more frequent customer interaction and a more consistent experience. We are pursuing strategies to deepen relationships with existing customers while attracting new ones with a suite of services that provides convenience, simplicity and flexibility. None of this would have happened without a great team of highly engaged employees focused on delivering for our customers, shareholders and communities.

Strategic Growth Investments

We are making meaningful investments in both our people and technologies, which positions us well for future growth. We added to our already strong capital position that will support organic or inorganic growth. We also augmented our legacy S&T leadership with team members who have experience at larger banks. Approximately half of our senior leadership team has experience at banks with more than $25 billion in assets. We have the people, products, infrastructure and capital to grow.

Awards & Recognition

These strategic investments, along with a focus on our financial performance drivers, are already delivering significant achievements that will further fuel our growth. For example, we are recognized as an industry leader in both employee engagement beingand customer experience. For two consecutive years, we have been named by Forbes as a Best-In-State Bank, which is based on the right sideresults of customer relationships and having active, meaningful involvement in the communities that we serve. Our business is built on trust. That was true when we were founded in 1902 and it’s just as true today. It’s foundationala consumer survey. We have also been named to the banking business and it’s certainly critical to our company.

Forbes list of America’s Best Midsize Employers, which includes companies from a wide range of industries, for two consecutive years. The S&T team must trust our leadership team, and believe we are taking our company in the direction where our employees can grow and succeed. Our employees also need to trust one another and keep in mind that none of us do our jobsForbes Best Employers list is based on our own. It’s essential to work as teams, and in a way that recognizes our role to serve others. Most importantly, our customers we serve and communities where we live and work must trust and know that we have their best interests at heart. We’re proud to have community banking roots that go back 120 years, and we intend to keep that successful approach.

Our shared future

2022 was also an important year for me as I was proud to take the helm for my first full year as CEO of S&T. Since the day I arrived, I have spent a great deal of time with our people – customers and employees- and am confident that we have developed a well-defined strategy that we can leverage, while adhering to the values that have helped us succeed across these many years.

And now we’re building upon that legacy to launch our next 120 years. We call it Our Shared Future, a future driven by our “People-Forward” purpose, underpinned by the values which enable S&T’s award-winning culture and make us who we are. We have summarized our values as follows:

With the claritysurveys of our purposecurrent and the power of our values, our people can do amazing things—and our customers succeed. We draw strength from these values, aligning S&T and our customers and communities for success for the long haul.

Delivering Results

S&T achieved record financial successformer employees, as well as significant industry recognitiontheir families and friends. In 2023, we were also honored by Energage, a leader in 2022.employee engagement surveys, as a top workplace in the United States and as a top workplace for work-life flexibility.

Community Partnerships & Brand Awareness

As a result of our marketing investments, as well as the outstanding contributions our employees make to build our people-forward brand, our brand awareness has grown significantlyin our Pennsylvania and Ohio markets during the past two years. Thanks to our more than 1,200 dedicated employees who have a passion for serving their communities, we assisted approximately 800 organizations by contributing more than 20,000 volunteer hours and donating more than $400,000.

Our industry recognition is highlighted by:Financial Achievements

The culmination of these efforts resulted in industry-leading financial results* for 2023, including:

Our financial performance included two consecutive quarters of record net income andRecord earnings per share (EPS) and record full year net income for the second consecutive full year.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF

PROXY MATERIALS FOR THE 20232024 ANNUAL MEETING OF SHAREHOLDERS

TO BE HELD ON MAY 16, 2023:14, 2024: OUR PROXY STATEMENT, 20222023 ANNUAL REPORT AND NOTICE OF

ANNUAL MEETING OF SHAREHOLDERS ARE AVAILABLE AT WWW.PROXYVOTE.COM

We are taking advantage of a rule of the Securities and Exchange Commission (the “SEC”) which allows companies to make proxy materials available on a public website rather than in paper form. This rule allows a company to send some or all of its shareholders a Notice of Internet Availability of Proxy Materials in place of the complete proxy package. For our 20232024 Annual Meeting, to save significant printing and mailing expenses, S&T mailed a Notice to certain shareholders who had not previously elected to receive their proxy materials through the mail on or about April 3, 2023,1, 2024, to inform them of the electronic availability of the proxy materials 40 days in advance of the Annual Meeting.

TABLE OF CONTENTS

S&T BANCORP, INC.

PROXY STATEMENT FOR

ANNUAL MEETING OF SHAREHOLDERS

TO BE HELD MAY 16, 202314, 2024

INTRODUCTION

This Proxy Statement is being furnished to shareholders of S&T Bancorp, Inc. in connection with the solicitation of proxies by the Board of Directors of S&T (the “S&T Board” or “Board”) for use at the Annual Meeting of Shareholders, and any adjournments thereof, to be held at the time and place set forth in the accompanying notice (“Annual Meeting”). We are first sending the Notice of Internet Availability of Proxy Materials, or this Proxy Statement, S&T’s 20222023 Annual Report and proxy card to shareholders on or about April 3, 2023.1, 2024.

At the Annual Meeting, shareholders of S&T will be asked to (i) elect 11 directors of S&T to serve a one-year term, (ii) approve the ratification of the selection of Ernst & Young LLP as S&T’s independent registered public accounting firm for the fiscal year 2023, and2024, (iii) approve, on a non-binding advisory basis, the compensation of S&T’s named executive officers (“NEOs”)., and (iv) approve, on a non-binding advisory basis, the frequency of future votes on the compensation of S&T’s named executive officers.

MEETING INFORMATION

Date, Time and Place

The Annual Meeting will be held on May 16, 2023,14, 2024, at 10:00 a.m. Eastern Time solely online via the Internet by going to www.virtualshareholdermeeting.com/STBA23STBA24. To participate in the Annual Meeting, you will need the 16-digit control number included on your Notice, on your proxy card or on the instructions that accompanied your proxy materials. See “Attending the Meeting; Virtual Meeting” below.

As permitted by S&T’s By-laws and applicable law, S&T chose towill hold the Annual Meeting in virtual format only. S&T commenced holding annual meetings in a virtual-only format in 2020, due to elevated health safety concerns for our shareholders from the Coronavirus pandemic.Annual Meeting. S&T decided towill continue holding annual meetings in virtualvirtual-only format only, so long as shareholders are served well through this medium, which we believe enhances accessibility to our Annual Meeting for all of our shareholders and reduces the carbon footprint of our activities.

Record Date, Voting Rights and Required Vote

The securities that can be voted at the Annual Meeting consist of shares of common stock of S&T, par value $2.50 per share (“Common Stock”), with each share entitling its owner to one vote on each matter to be voted on at the Annual Meeting. There are no cumulative voting rights with respect to the Common Stock. Only holders of the Common Stock at the close of business on February 28, 20232024 (the “Record Date”) are entitled to notice of and to vote at the Annual Meeting. There were 38,998,24138,273,189 shares of Common Stock outstanding as of the Record Date.

A quorum is required for the transaction of business at the Annual Meeting. A “quorum” is the presence at the meeting, virtually (i.e., online via www.virtualshareholdermeeting.com/STBA23STBA24) or represented by proxy, of the holders of the majority of the outstanding shares of Common Stock entitled to vote at the meeting. Abstentions are counted for purposes of determining the presence or the absence of a quorum but are not considered a vote cast under Pennsylvania law. Under our governing documents and applicable state law, abstentions will not affect the outcome of a vote on a particular matter. Broker non-votes are counted to determine if a quorum is present but are not considered a vote cast under Pennsylvania law. Under our governing documents and applicable state law, broker non-votes will not affect the outcome of a vote on a

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Meeting Information

particular matter. Generally, broker non-votes occur on a matter when a bank, broker or other nominee is not permitted to vote on that matter without instructions from the beneficial owner and such instructions are not given. Banks, brokers and other nominees have discretionary authority to vote shares in the absence of instructions on matters considered “routine,” such as the ratification of the appointment of the independent registered public accounting firm. They do not have discretionary authority to vote shares in the absence of instructions on “non-routine” matters, such as the election of directors, the advisory vote on compensation of S&T’s NEOs and the advisory vote to approveon the frequency of future votes on the compensation of S&T’s “NEOs”.NEOs.

The director nominees will be elected by a plurality of the votes cast at the Annual Meeting, which means that the 11 nominees receiving the most votes will be elected. A withheld vote on any nominee will not affect the voting results. Under S&T’s voting standard policy adopted by the S&T Board, which is included in S&T’s Corporate Governance Guidelines (“Guidelines”), if a director nominee in an uncontested election at the Annual Meeting receives a greater number of “withheld” votes from his or her election than votes “for” such election, such director must submit his or her resignation to the Board promptly following the certification of election results. The resignation will first be considered by the members of the Nominating and Corporate Governance Committee (the “Nominating Committee”) within 60 days following certification of the shareholder vote. The Nominating Committee will recommend to the S&T Board whether to accept or reject the resignation after considering all factors deemed relevant by the Nominating Committee. The S&T Board shall act on the Nominating Committee’s recommendation within 90 days following certification of the shareholder vote. If a director’s resignation is accepted by the Board, the Board either may fill the resulting vacancy or may decrease the size of the Board pursuant to S&T’s By-laws, as amended and restated (the “By-laws”).By-laws.

The ratification of the selection of Ernst & Young LLP as S&T’s independent registered public accounting firm for fiscal year 2023,2024, the approval, on a non-binding advisory basis, of the compensation of S&T’s NEOs and the approval, on a non-binding advisory basis, of the frequency of future votes on the compensation of S&T’s NEOs require the affirmative vote of a majority of the votes cast at the Annual Meeting to be approved.

Voting and Revocation of Proxies

Shareholder of Record. If you are a shareholder of record and you received the Notice, you may vote before the Annual Meeting by accessing the secure Internet website registration page identified on the Notice and following the instructions. You may also vote electronically during the virtual Annual Meeting if you participate.

If you are a shareholder of record and you received a printed copy of the proxy materials, you may vote by proxy by telephone, using the Internet or by mailing your proxy card, as further described below. You may also vote electronically during the virtual Annual Meeting if you participate.

By Telephone:		By Internet:		By Mail:
Call the toll-free telephone number on the enclosed proxy card (1-800-690-6903) and follow the recorded instructions.		Access the secure Internet website registration page on the enclosed proxy card and follow the instructions.		Sign, date and return your proxy card in the postage-paid envelope provided.

If you vote by proxy via telephone or the Internet, you do not need to mail your proxy card. The individuals named as proxies on your proxy card will vote your shares of Common Stock during the Annual Meeting as instructed by the latest dated proxy received from you, whether submitted via the Internet, telephone or mail. If you sign your proxy card but do not specify how you want your shares voted on any matter, you will be deemed to have directed the proxies to vote your shares as recommended by the S&T Board.

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Meeting Information

Beneficial Owners. If your shares of Common Stock are held in a stock brokerage account by a bank, broker or other nominee, you are considered the beneficial owner of shares held in street name and these proxy materials are being forwarded to you by your bank, broker or other nominee that is considered the shareholder of record of those shares.

As the beneficial owner, you have the right to direct your bank, broker or other nominee on how to vote your shares of Common Stock via the Internet or by telephone, if the bank, broker or other nominee offers these options, or by completing, signing, dating and returning a voting instruction form. Your bank, broker, or other nominee will send you instructions on how to submit your voting instructions for your shares of Common Stock.

If you properly complete, sign, date and return the voting instruction form, your shares of Common Stock will be voted as you specify. If you are a beneficial owner and you do not provide voting instructions to your bank, broker or other nominee holding shares of Common Stock for you, your shares of Common Stock will not be voted with respect to any proposal for which the shareholder of record does not have discretionary authority to vote.

Except for procedural matters incident to the conduct of the Annual Meeting, S&T does not know of any matters other than those described in the Notice of Annual Meeting of Shareholders that are to come before the Annual Meeting. If any other matters are properly brought before the Annual Meeting, the persons named in the proxy will vote the shares represented by the proxies in their discretion on such matters as recommended by a majority of the S&T Board.

Revocation of Proxies. The presence of a shareholder at the virtual Annual Meeting will not automatically revoke such shareholder’s proxy. However, a shareholder may revoke a proxy at any time prior to its exercise by filing with the Secretary of S&T a written notice of revocation, by delivering to S&T a duly executed proxy bearing a later date or by voting electronically during the virtual Annual Meeting.

Attending the Meeting; Virtual Meeting

You may attend the webcast of the meeting via the Internet at www.virtualshareholdermeeting.com/STBA23STBA24 when you enter the 16-digit control number included on your Notice, on your proxy card or on the instructions that accompanied your proxy materials. Instructions on how to attend and participate in the Annual Meeting via the webcast are posted at www.virtualshareholdermeeting.com/STBA23STBA24. You will be able to vote your shares while attending the Annual Meeting by following the instructions on the website. Our management will address questions from shareholders who have submitted their questions electronically prior to and during the Annual Meeting. You may visit www.proxyvote.com at any time prior to the Annual Meeting to ask questions of our executive management that may be addressed in the Annual Meeting and access information about S&T. Even if you plan to participate in the Annual Meeting, we urge all shareholders to vote on the matters listed above and described in the Proxy Statement as soon as possible, so that your vote will be counted if you later decide not to participate in the Annual Meeting.

Solicitation of Proxies

The cost of soliciting proxies will be borne by S&T. S&T has engaged D.F. King & Co., Inc. to help solicit proxies for the Annual Meeting, and will pay D.F. King & Co., Inc. $9,000, plus its out-of-pocket expenses, for the solicitation of proxies. In addition to the solicitation of proxies by mail, S&T may also solicit proxies personally, by telephone or by electronic means, through its directors, officers and regular employees. None of these directors, officers or employees will receive any additional or special compensation for soliciting proxies. S&T also will request persons, firms and corporations holding shares of Common Stock in their names or in the name of their nominees, which are beneficially owned by others, to send proxy materials to and obtain proxies from the beneficial owners and will reimburse the holders for their reasonable expenses in so doing.

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Meeting Information

Internet Availability of Proxy Materials

S&T’s Proxy Statement for the Annual Meeting and S&T’s 20222023 Annual Report are available at www.proxyvote.com. You will enter your 16-digit control number included on your Notice, on your proxy card or on the instructions that accompanied your proxy materials to access these materials.

Householding

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for Notices or proxy statements and annual reports with respect to two or more shareholders sharing the same address by delivering a single Notice or proxy statement and annual report addressed to those shareholders. This process is commonly referred to as “householding.”

S&T has implemented “householding” to reduce the number of duplicate mailings to the same address. This process benefits both shareholders and S&T because it eliminates unnecessary mailings delivered to your home and helps to reduce S&T’s expenses. “Householding” is not being used, however, if S&T has received contrary instructions from one or more of the shareholders sharing an address. If your household has received only one Notice or one annual report and proxy statement, S&T will deliver promptly a separate copy of the Notice or annual report and proxy statement to any shareholder who contacts S&T by calling the toll-free number, 1-800-325-2265, or by mail to the attention of the Secretary of S&T at 800 Philadelphia Street, Indiana, Pennsylvania 15701. You can also notify S&T that you would like to receive separate copies of the Notice or S&T’s annual report and proxy statement in the future by calling or mailing S&T, as instructed above. If your household has received multiple copies of the Notice or S&T’s annual report and proxy statement, you can request the delivery of single copies in the future by calling or mailing S&T, as instructed above, or your broker, if you hold the shares in “street name.”

If you received more than one Notice or proxy card, it means that your shares are registered in more than one name (e.g., trust, custodial accounts, joint tenancy) or in multiple accounts. Please make sure that you vote all of your shares by following the directions on each Notice or on each proxy card that you received.

For our 20242025 annual meeting, you can help us save significant printing and mailing expenses by consenting to access our proxy materials electronically via the Internet. If you hold your shares in your own name (instead of “street name” through a bank, broker or other nominee), you can choose this option by following the prompts for consenting to electronic access, if voting by telephone, or by following the instructions at the Internet voting website at www.proxyvote.com, which has been established for you to vote your shares for the 20232024 Annual Meeting. If you choose to receive your proxy materials electronically, then prior to next year’s annual meeting, you will receive notification when the proxy materials are available for online review via the Internet, as well as the instructions for voting electronically via the Internet. Your choice for electronic distribution will remain in effect until you revoke it by sending a written request to S&T by mail to the attention of the Secretary of S&T at 800 Philadelphia Street, Indiana, Pennsylvania 15701. If you hold your shares in “street name” through a bank, broker or other nominee, you should follow the instructions provided by that entity if you wish to access our proxy materials electronically via the Internet.

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BENEFICIAL OWNERS OF S&T COMMON STOCK

Under Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), a beneficial owner of a security is any person who directly or indirectly has or shares voting power or investment power over such security. Such beneficial owner under this definition need not enjoy the economic benefit of such securities. The following are the only shareholders known to S&T to be deemed to be a beneficial owner of 5% or more of Common Stock as of February 28, 2023,2024, when 38,998,24138,273,189 shares of Common Stock were outstanding. S&T has relied solely on information provided in the public filings made by the holders below:

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BENEFICIAL OWNERSHIP OF S&T COMMON STOCK BY DIRECTORS AND OFFICERS

The following table sets forth, as of February 28, 2023,2024, the amount and percentage of Common Stock beneficially owned by each director, each nominee for director and each of the “NEOs” (as defined below) of S&T, as well as the directors and executive officers of S&T as a group. Unless otherwise indicated, all persons listed below have sole voting and investment power over all shares of Common Stock. The business address of each of S&T’s directors and officers is 800 Philadelphia Street, Indiana, Pennsylvania 15701.

Delinquent Section 16(a) Reports

Section 16(a) of the Exchange Act requires S&T’s directors and executive officers, and persons who own more than 10% of Common Stock, to report to the SEC certain of their transactions with respect to S&T’s Common Stock. The SEC reporting rules require that changes in beneficial ownership generally be reported on Form 4 within two business days after the date on which the change occurs. A Form 3 to report stock holdings in S&T must be filed within ten days of when a director, executive officer or person who owns more than 10% of S&T’s stock becomes subject to Section 16(a) of the Exchange Act.

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PROPOSAL 1: ELECTION OF DIRECTORS

General

The S&T Board determines the number of directors to nominate for election. The By-laws of S&T provide that the number of directors constituting the S&T Board will consist of not less than nine nor more than 17, with the exact number to be fixed and determined from time to time by resolution of a majority of the S&T Board. For this annual meeting, the Board fixed the number of directors to be elected at 11.

There are currently 1112 directors comprising the S&T Board.Board, however, Steven J. Weingarten intends to retire from the Board effective upon the expiration of his term immediately following the Annual Meeting. The S&T Board has nominated the 11 persons named below for election at the Annual Meeting, all of whom are incumbent directors upstanding for re-election. Proxies cannot be voted for a greater number of persons than the number of nominees named in this Proxy Statement.

The nominees were each recommended by our Nominating Committee recommended each of the nominees to the S&T Board. Directors are elected annually, and each director nominee elected at the Annual Meeting will serve for a term expiring at the 20242025 S&T Annual Meetingannual meeting of Shareholders,shareholders, until his or her successor has been elected and qualified, or until his or her earlier death, resignation, removal or disqualification. All nominees have indicated their willingness to serve, if elected, but if any should be unable to serve or unwilling to serve for good cause, proxies may be voted for a substitute nominee designated by the S&T Board. There are no family relationships between or among any of our directors, executive officers or persons nominated or chosen to become a director or executive officer. Unless otherwise instructed, the proxy holders will vote the proxies received by them for the nominees named below.

Set forth below is a brief description of the principal occupation and business experience of each of our nominees for director, as well as a summary of the qualifications of each nominee and continuing director to serve on the S&T Board. The S&T Board has had significant experience with each of the incumbent directors and has had the opportunity to assess the contributions that each director has made to the S&T Board as well as each director’s industry knowledge, judgment and leadership capabilities. The Nominating Committee continually assesses the tenure and diversity of the S&T Board and seeks opportunities, within the constraint of the size of the S&T Board, to include a mix of directors with S&T Board experience and with fresh perspectives. The average tenure of the S&Tcurrent Board is 11.7 years and S&T’s Guidelines include a mandatory director retirement age of 72. In the last sixseven years, the Nominating Committee has had the opportunity to add six (55%seven (64% of the 11 director nominees) new directors to the S&T Board to further diversify the S&T Board’s industry knowledge, experience, judgment, gender, minority status and leadership capabilities. The S&T Board has two female directors, and one African American director and one Asian director. The following directors were appointed to the S&T Board in the last sixseven years: Christina A. Cassotis, David G. Antolik, Lewis W. Adkins, Jr., Peter R. Barsz, William J. Hieb, and Christopher J. McComish.McComish, and Bhaskar Ramachandran.

S&T seeks director candidates who will uphold the highest standards, are committed to S&T’s values, and who will be strong independent stewards of the long-term interests of shareholders. In selecting nominees, our Board looks for individuals with demonstrated experience and success in fields that are relevant to our business, strategy and operations, and who will contribute diverse viewpoints and perspectives.

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Proposal 1: Election of Directors

collaborative approach to engagement and oversight, inquisitive and objective perspective, and a willingness to challenge management appropriately. In addition, our nominees have executive experience and skills that are aligned with our business and strategy, including the following:

Director Nominees for Election at the 20232024 Annual Meeting:

		Lewis W. Adkins, Jr., Age 5960
		Director since 2019		Committees: • Credit Risk • Nominating & Corporate Governance

Biographical Information

Mr. Adkins is a Shareholder and Shareholder-in-Charge of Development & Practice Group Manager of Public Law, Regulatory and FinanceIntegration for Roetzel & Andress, LPA, a full-service law firm with offices located throughout Ohio, Florida and Chicago,Chicago. Additionally, since January 2000. Additionally,May 2017, he ishas served as President of their wholly-owned consulting subsidiary, Roetzel Consulting Solutions, a bipartisan consulting company representing clients where the private and public sectors intersect, since May 2017.intersect. Mr. Adkins previously served as General Counsel to Summit County, Ohio. Mr. AdkinsHe is affiliated with numerous professional and charitable organizations including Board Chair for the University of Akron Board of Trustees, Summa Health Finance Committee,Ideastream Public Media Board of Trustees, the American Bar Association, the National Democratic Club, the Greater Akron Chamber of Commerce, Alpha Phi Alpha Fraternity, Inc. and the Cleveland Metropolitan Bar Association Diversity Action Committee.Association.

Experience and Qualifications

Mr. Adkins also has extensive experience servingacted as lead counsel tofor several multi-million-dollar development projects. His clients across a vast number of industries includinginclude public and private entities, as well as construction companies, engineering firms, financial institutions, diversified energy companies, governmental entities, housing authorities, urban school districts and nonprofit organizations. Prior to assuming his current leadership role, Mr. Adkins led for over a decade Roetzel & Andress, LPA’s Public Law and Finance team as Practice Group Manager. Additionally, he is currently General Counsel to Alpha Phi Alpha Homes, Inc.. He also serves as lead counsel for a number of public and private entities including Ohio’s largest banking institution, a regional public hospital and two of Ohio’s largest school districts. Mr. Adkins’ expansive business and legal knowledge and his community leadership provide the S&T Board with public finance, business development, and strategic management experience which qualifies him to serve on the S&T Board.

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Proposal 1: Election of Directors

		David G. Antolik, Age 5657
		Director since 2019 President

Biographical Information

Mr. Antolik has been President of S&T and S&T Bank since January 2019. He was Interim Chief Executive Officer and President from April 1, 2021 to August 23, 2021. Mr. Antolik was Chief Lending Officer of S&T and S&T Bank from 2008 to October 2020. He previously served as Senior Executive Vice President of S&T and S&T Bank from 2008 until January 2019. Mr. Antolik also serves as the chairman of the IUP Research Institute and is a member of the Indiana County Development Corporation Board.

Experience and Qualifications

With 3435 years of banking experience, including 1516 years of senior management experience at S&T, Mr. Antolik’s strong leadership capabilities and in-depth industry experience in commercial banking and implementing strategic initiatives provide the S&T Board with expertise that will contribute to the strategic growth of S&T. As our past Interim Chief Executive Officer and current President, Mr. Antolik provides unique insight to the S&T Board regarding our day-to-day operations, customer information, competitive intelligence, general trends in national and local banking and issues regarding our financial results.

		Peter R. Barsz, Age 6667
		Director since 2019		Committees: • Audit • Compensation & Benefits • Nominating & Corporate Governance

Biographical Information

Mr. Barsz is a Certified Public Accountant and has been a Partner at Barsz Gowie Amon & Fultz, LLC, an accounting firm, since July 2017 when Steger Gowie & Company merged with Merves Amon & Barsz LLC where Mr. Barsz became a partner in 1990. Mr. Barsz previously served on the board of DNB, the holding company for DNB First, N.A., from January 2018 until it was acquired by S&T in November 2019. Mr. Barsz serves as the appointed Treasurer and has served as the Finance Director of several municipalities in Chester and Delaware counties and is currently serving as Chairman of the Pennsylvania State Tax Equalization Board, an independent agency of the Commonwealth tasked with obtaining information on real estate sales throughout the state. Mr. Barsz also received an appointment by the Pennsylvania Legislature and is currently serving as a public member on the Legislative Audit Advisory Committee for the current and past three Legislative Sessions of the General Assembly. Mr. Barsz previously served as a director of two real estate holding companies located in Media, Pennsylvania as well as the Treasurer of the Foundation of the Delaware County Chamber of Commerce.

Experience and Qualifications

Mr. Barsz’s extensive experience in accounting and providing management and financial consulting services to governmental and nonprofit entities, his deep community engagement, as well as his broad financial perspective qualify him to serve on the Audit Committee as an “audit committee financial expert” and on the S&T Board.

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Proposal 1: Election of Directors

		Christina A. Cassotis, Age 5859
		Director since 2017		Committees: • Audit • Compensation & Benefits (Chairperson) • Executive • Risk

Biographical Information

Ms. Cassotis has been the chief executive officer of the Allegheny County Airport Authority, which operates Pittsburgh International Airport and Allegheny County Airport since January 2015. Prior to that, Ms. Cassotis joined SH&E, Inc. in 1999, a global commercial aviation consulting firm, where she advised airports worldwide on strategy, business, and system planning. She went on to serve as managing officer for Airport Services for ICF-SH&E from 2007 to 2014, leading a global team of airport consultants. She also serves as a member of the board for the U.S. Travel Association, a member of the Board at the Federal Reserve Bank of Cleveland (Pittsburgh Branch) and a member of the International Aviation Women’s Association. Ms. Cassotis served as a director of EQT Corporation from October 2018 until July 2019.

Experience and Qualifications

Ms. Cassotis has demonstrated that she is a strong, decisive, and strategic leader. Her ability to identify the complex relationship between organizations and the competitive environments in which they operate has allowed her to position her business interests for the future while paying attention to immediate demands. Her substantial leadership roles within a highly-regulated, high-stakes industry provide valuable risk oversight experience, including with respect to cyber and technology, to the S&T Board. She is an innovative leader who has successfully directed necessary change through organizations to drive growth and deliver value which qualifies her to serve on the S&T Board.

		Michael J. Donnelly, Age 6566
		Director since 2001		Committees: • Compensation & Benefits • Credit Risk

Biographical Information

Mr. Donnelly has been president of Indiana Printing and Publishing Company, Inc. since 1993. Mr. Donnelly has spent over 30 years working with the Indiana County Chamber of Commerce and the Indiana County Development Corporation in retaining and attracting many businesses in the Indiana, Pennsylvania area.

Experience and Qualifications

Mr. Donnelly’s deep experience in managing and operating a local business provides the S&T Board with valuable insight into the issues addressing our local corporate and consumer borrowers. Mr. Donnelly’s experience in developing appropriate compensation for the executives and senior management of his company qualifies him to serve on the S&T Board.

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Proposal 1: Election of Directors

		Jeffrey D. Grube, Age 6970
		Director since 1997		Committees: • Audit • Compensation & Benefits • Credit Risk (Chairperson) • Executive • Risk

Biographical Information

Mr. Grube served as president of B.F.G. Manufacturing Service, Inc., which provides large volume plating, painting and powder coating services with facilities in Pennsylvania and New York from 1990 until his retirement in 2020. Mr. Grube’s career as an executive in the manufacturing industry includes financial and engineering experience. Mr. Grube also served as a director on the board of a privately held company that supplies compliance products for lending solutions.

Experience and Qualifications

Mr. Grube’s extensive experience working with small and medium-sized businesses provides the S&T Board with valuable experience regarding potential borrowers and customers, customer relations, lending issues and credit risk. Mr. Grube’s executive and board experience in the manufacturing sector and experience with financial institutions allow him to bring relevant insight regarding regulatory and financial compliance issues to the S&T Board.

		William J. Hieb, Age 6667
		Director since 2019		Committees: • Credit Risk • Executive • Risk (Chairperson)

Biographical Information

Mr. Hieb served as the president and chief executive officer of DNB, the holding company for DNB First, N.A. since April 2016 until it was acquired by S&T in November 2019. He was a director of DNB since 2005 and a director of DNB First, N.A. since 2004. Mr. Hieb served as president and chief risk & credit officer of DNB from April 2011 to January 2016. Prior to that, Mr. Hieb served as president and chief operating officer of DNB from January 2005 to April 2011. Mr. Hieb is a board member of West Chester University’s President Corporate Advisory Council. Mr. Hieb has previously served on the board of directors for the Chester County Chamber of Business and Industry, the Chester County Historical Society, the Chester County Economic Development Council, the Chester County Chamber of Business and Industry and its Foundation, the Pennsylvania Bankers Association, and Thethe Housing Partnership of Chester County and Business Leadership Organized for Catholic Schools.Schools, and the West Chester University’s President Corporate Advisory Council.

Experience and Qualifications

Mr. Hieb has acquired considerable knowledge and experience during his 41 years in commercial banking including lending, credit administration, and wealth management. In addition, his background supervising DNB’s risk management function and operations during his career strengthens the Board’s collective qualifications, skills, and experience, and qualifies him to serve on the S&T Board.

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Proposal 1: Election of Directors

		Christopher J. McComish, Age 5859
		Director since 2021 Chief Executive Officer		Committees: • Executive

Biographical Information

Mr. McComish has been Chief Executive Officer of S&T and S&T Bank since August 24, 2021. Previously, he was senior executive vice president of consumer banking of TCF Bank, leading all consumer banking lines of business as well as business banking and wealth management from July 2018 to June 2021. Prior to TCF Bank, he served as president and chief executive officer of Scottrade Bank, the banking subsidiary of Scottrade Financial Services, Inc. from August 2015 to December 2017. In addition, he served as head of personal banking and then as chief operating officer for personal and commercial banking at BMO Harris Bank from December 2008 to July 2015. He began his career at Wachovia Bank, where he spent over 20 years in various regional and line of business leadership roles.

Experience and Qualifications

With more than 3536 years of banking experience, including 2021 years of senior management experience in his banking career, Mr. McComish’s strong leadership capabilities as a former chief executive officer, president and chief operating officer at other banking institutions and as senior executive vice president with a larger bank in the Midwest, provide the S&T Board with expertise that contributes to the strategic growth of S&T. As our Chief Executive Officer, Mr. McComish provides in-depth industry experience and insight in commercial banking, consumer banking, business banking and wealth management from a larger bank perspective. He is familiar with the impact of technology on banking, having served as the chief executive officer of a digital online bank, and brings to the S&T Board technology risk management experience. He also provides unique insight to the S&T Board regarding our day-to-day operations, risk and strategic initiatives, general trends in national and local banking, and issues regarding our financial results.

		Frank J. Palermo, Jr., Age 7071
		Director since 2013		Committees: • Audit (Chairperson) • Executive • Nominating & Corporate Governance • Risk

Biographical Information

Mr. Palermo is a Certified Public Accountant and has been the managing shareholder of Palermo/Kissinger & Associates, P.C., an accounting firm, since 1983. Mr. Palermo played an integral role in forming Gateway Bank of Pennsylvania (“Gateway”), where he served as chairman of the audit committee from its inception in 2004 through the date S&T acquired Gateway in 2012. Previously, Mr. Palermo served as a Certified Valuation Analyst as well. Mr. Palermo’s career also includes 43 years in public accounting and five years as a vice president and controller at a community bank.

Experience and Qualifications

Mr. Palermo’s background in accounting and finance, as well as his prior bank audit committee experience, bring a valuable perspective to the S&T Board both with respect to accounting, financial, and strategic aspects of S&T’s business and to the Audit Committee on which he serves as an “audit committee financial expert.” Mr. Palermo’s extensive board experience qualifies him to serve on the S&T Board.

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Proposal 1: Election of Directors

		Bhaskar Ramachandran, Age 50
		Director since 2024

Biographical Information

Mr. Ramachandran has served as Global Vice President and Chief Information Officer of PPG Industries, Inc., a 140-year old Pittsburgh-based leading paints and coatings company, since 2021. From 2015 until joining PPG, Mr. Ramachandran served as Vice President, Information Technology, and Chief Information Officer of the largest division, of Jabil Inc., an American worldwide manufacturing services company. At Jabil, Inc., he led the creation of a fully cloud-based connected eco-system to make production more efficient and cost-effective. Prior to joining Jabil, Inc., Mr. Ramachandran progressed through information technology roles of increasing responsibility at Textron, Inc., a multi-industry company, where he was accountable for strategy development and operational elements of Textron, Inc.’s SAP center of excellence.

Experience and Qualifications

Mr. Ramachandran’s deep knowledge of cybersecurity and information technology provide the Board with valuable cyber and technology risk expertise, as well as a strong understanding of digital business strategies and emerging technology. Mr. Ramachandran’s extensive leadership experience at large, regulated companies, including his proven track record in scaling and transforming businesses, brings a diverse range of skills and knowledge that further contribute to an engaged and well-balanced Board. His work developing and leading diverse, high-performing teams across different industries and global companies also provides the Board with a unique perspective on people, process, adaptability and emotional intelligence.

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Proposal 1: Election of Directors

		Christine J. Toretti, Age 6667
		Director since 1984		Committees: • Executive (Chairperson) • Risk

Biographical Information

Ms. Toretti was named Chairperson of the S&T Board and S&T Bank Board in 2018 and was formerly Vice Chairperson of the S&T Board and S&T Bank Board from 2013 to 2018. Ms. Toretti has been the president of Palladio, LLC, an investment holding company headquartered in Indiana, Pennsylvania, since 2011, was the chairman and chief executive officer of S.W. Jack Drilling Company from 1990 through 2010 and was the president of The Jack Company from 1988 through 2015. Ms. Toretti has been the president of Plum Production, Inc. since 1991, and president of CJT, LLC since 2002, each of which is a natural gas investment company. Ms. Toretti served as a director of EQT Corporation from October 2015 until July 2019.

Experience and Qualifications

Ms. Toretti’s deep industrial and energy experience provides the S&T Board with a strategic outlook regarding lending and other commercial opportunities in these sectors. Her experience of leading a family business allows her to offer the S&T Board valuable management perspective and credit risk assessment with respect to our industrial and oil and gas borrowers, and her board experience, including in the role of chairperson of another company, qualifies her to serve as Chairperson of the S&T Board.

		Steven J. Weingarten, Age 64
		Director since 2015		Committees: • Compensation & Benefits • Executive • Nominating & Corporate Governance (Chairperson) • Risk

Biographical Information

Mr. Weingarten was an attorney at McNees Wallace & Nurick LLC from 1989 until 2019 and was a member there beginning in 1993. Additionally, he served as managing partner of McNees Wallace & Nurick LLC from 2002 to 2006. Mr. Weingarten previously served on the board of Integrity Bankshares, Inc. (Integrity) from 2003 until it was acquired by S&T in March 2015. Mr. Weingarten retired from the practice of law effective April 30, 2019. Until late 2021, Mr. Weingarten was involved in real estate investment as a member of TAV Partners, LP.

Experience and Qualifications

Mr. Weingarten’s experience in managing McNees Wallace & Nurick LLC and in practicing real estate law, and the knowledge he gained from his service as a director of Integrity, qualify him to serve on the S&T Board.

Board Recommendation

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CORPORATE GOVERNANCE

Corporate Governance Guidelines

The S&T Board has developed and adopted the Guidelines which reflect S&T’s commitment to following corporate governance best practices. The Guidelines are intended to promote the functioning of the S&T Board and its committees and provide a common set of expectations as to how the S&T Board should perform its functions. These Guidelines are not intended to modify or amend S&T’s Articles of Incorporation, as amended (the “Articles of Incorporation”) or By-laws. In the event of a discrepancy between these Guidelines and the Articles of Incorporation or the By-laws, the Articles of Incorporation and By-laws will always govern. The Guidelines are available on S&T’s website, www.stbancorp.com, under Corporate Governance.

Director Independence

The S&T Board annually reviews and makes a determination as to the independence of its directors under the NASDAQ listing rules. In 2022,2023, the S&T Board also considered all direct and indirect transactions described under “Transactions with Related Parties” in determining whether a director is independent. Finally, the S&T Board considered whether a director has any other material relationships with S&T and concluded that none of S&T’s directors, other than Mr. Antolik and Mr. McComish, has any such relationship that impairs the director’s independence. There were no other related party transactions other than those described under “Transactions with Related Parties” in this Proxy Statement. The Nominating Committee has the delegated responsibility to evaluate each director’s qualifications for independence for the S&T Board and for the committees of the S&T Board. In accordance with the NASDAQ listing rules and interpretations, following review of the objective measures, the Nominating Committee and S&T Board also evaluate on a subjective basis each director’s personal, familial and/or business relationship, regardless of dollar amount.

OnAt a meeting held on January 25, 2023,24, 2024, the S&T Board affirmatively determined the following nine directors and director nominees are independent under the NASDAQ listing rules: Mr. Adkins, Mr. Barsz, Ms. Cassotis, Mr. Donnelly, Mr. Grube, Mr. Hieb, Mr. Palermo, Mr. Ramachandran, and Ms. Toretti, andToretti. Mr. Weingarten.Weingarten, who intends to retire from the S&T Board effective upon the expiration of his term immediately following S&T’s annual shareholder meeting, was also determined to be independent by the Board under the NASDAQ listing rules. As discussed below, all members of the Compensation and Benefits Committee (the “Compensation Committee”) and the Nominating Committee are independent under the NASDAQ rules. In addition, the S&T Board determined that each of the members of the Audit Committee is independent under applicable SEC and NASDAQ rules. The S&T Board affirmatively determined that Mr. Antolik and Mr. McComish are the only non-independent directors as each is an executive officer of S&T. Robert E. Kane, who served as a director until May 16, 2022 when he did not stand for re-election, also qualified as independent duringIn making these determinations, the period he servedBoard relied on the S&T Board.evaluation and recommendations made by the Nominating Committee. 

Board Structure; Board and Committee Meetings

There are currently 1112 directors comprising the S&T Board.Board, however, Steven J. Weingarten intends to retire from the Board effective upon the expiration of his term immediately following the Annual Meeting. The S&T Board currently has established six standing committees: Audit, Compensation and Benefits, Credit Risk, Executive, Nominating and Corporate Governance, and Risk. Each Board Committee serves as a board committee of S&T Bank in addition to being a Board committee of S&T.

During 2022,2023, the S&T Board held eightseven board meetings, with the following number of meetings held by the S&T Board committees: Audit, four;eight; Compensation and Benefits, five; Credit Risk, four; Nominating and Corporate Governance, four; and Risk, four. The Executive Committee, which meets as often as it determines is necessary and appropriate, did not meet during 2022. 2023.

Each director of the Board attended at least 75% of the aggregate number of meetings of the S&T Board and the committees on which he or she served during 2022.2023. Independent members of the S&T Board meet at least twice per year in regularly scheduled executive sessions without management present. The independent Chairperson of the Board presides over all executive sessions. The S&T Board has implemented a formal policy that strongly encourages director attendance at the annual meeting of shareholders. In 2022,2023, all of S&T’s directors attended the annual meeting of shareholders.

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Corporate Governance

Separate Roles of Chairperson and Chief Executive Officer

The S&T Board believes that, as part of our efforts to embrace and adopt good corporate governance practices, different individuals should hold the positions of Chairperson of the Board and Chief Executive Officer (“CEO”) to aid in the S&T Board’s oversight of management. The S&T Board believes that separation of the roles of Chairperson and CEO is the best governance model for S&T and its shareholders at this time. Under this model, our Chairperson, a non-executive position, can devote his or her attention to assuring that S&T has the proper governance controls in place; that the S&T Board is properly structured from the standpoints of membership, size and diversity; and that management has the support it needs from the S&T Board to carry out our strategic priorities. The CEO, relieved of the duties normally performed by the Chairperson, is free to focus his or her entire attention on growing and strengthening the business.

The duties of the non-executive Chairperson of the Board include:

We believe that the current composition of the S&T Board, the S&T Board committees as presently constituted and the leadership structure of the S&T Board enable the S&T Board to fulfill its role in overseeing and monitoring the management and operations of S&T and to protect the interests of S&T and its shareholders.

The S&T Board’s Role in Risk Oversight

Role of the S&T Board

The S&T Board with the assistance of the Risk Committee, whose members constitute the Board Chairperson and the chairpersons from each of the Board Committees discussed below, oversees an enterprise-wide approach to risk management (“ERM”), designed to support the achievement of strategic goals, to improve long-term organizational performance and to enhance shareholder value. The Board’s oversight primarily focuses on material risks and any notable emerging themes to ensure S&T’s risk management is adequate. The chair of the Risk Committee, in collaboration with the Board Chairperson, helps ensure that the Board has appropriate discussions on risk topics. The Risk Committee is responsible for reviewing and recommending to the Board for approval certain risk appetites taking into account S&T’s structure, risk profile, complexity, activities, size, and other appropriate risk-related factors. The Risk Committee considers current risks, which include the respective timeframes reflected by those risks, emerging risks, and future threats.

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Corporate Governance

The Risk Committee is responsible for overseeing S&T’s risk management activities and the effectiveness of its ERM framework. The Risk Committee is also responsible for monitoring our compliance risk with respect to regulatory and legal matters. DirectorPer the Risk Committee charter, the chairperson of the Risk Committee must satisfy the independence requirements established by the SEC, NASDAQ and any other governmental or regulatory body with authority over S&T. Mr. Hieb, Risk Committee Chairperson, meets thesuch independence standards for directors required by the SEC and NASDAQ.standards. The Risk Committee recommends to the S&T Board the risk appetite or broad level of risk that is appropriate for S&T to accept. S&T’s risk appetite is an important piece of an effective ERM framework that reinforces risk culture and is a core instrument for better aligning overall corporate strategy, capital allocation, and risk.

Our Risk Committee’s primary purpose is to provide assistance toassist the Board in fulfilling its fiduciary responsibilities with respect to its oversight and assessment of S&T’s ERM framework, including among other things, the identification, assessment, measurement, monitoring, and management of the following major risk categories: Credit, Market, Liquidity, Operational, Information Technology Operational and Security, Compliance, Legal, Reputational, and Strategic. The Risk Committee meets quarterly or as often as it determines is necessary and appropriate. As with the other committees of the Board, the Risk Committee has the authority to consult with outside advisors as it deems necessary or appropriate to discharge its duties and responsibilities.

The S&T Board, with the assistance of the Risk Committee, of the Board, delegates the authority and responsibility for and ensuring alignment of the risk appetite with the strategic objectives to the management-level Enterprise Risk Management Committee (the “ERM Committee”). The ERM Committee serves as the primary risk management forum for monitoring S&T’s risk exposures by reviewing key risk indicators or guidelines to proactively monitor both the level and direction of risk as well as key performance indicators to monitor progress toward achievement of strategic goals. By utilizing a comprehensive and standardized view of the nature and level of risk to which we areS&T is exposed and the interaction of the various risk components identified in ourits ERM program, we areS&T is better able to assess and manage ourits risk and react to uncertainties.

The ERM Program utilizes a three lines of defense model to delegate responsibility for critical risk management processes across the business functions and operational areas, as well as risk management, compliance, and internal audit teams. S&T’s first line of defense consists of business areas and operational teams across S&T Bank,Bank. These areas and isteams are responsible for identifying, assessing, mitigating, monitoring, and managing risk within their respective areas. The Bank’s risk management functions represent the second line of defense. These functions are led by the Chief Risk Officer (“CRO”) and includesinclude a team consisting of a Deputy CRO,Director of Risk Management, Chief Appraisal Officer, Chief Compliance Officer, Chief Security Officer, Director of Credit Risk Review and Director of Operational Risk Management. S&T’s Audit and Advisory Department represents the third line of defense, which provides independent and objective assurance to senior management and the Board regarding first and second line risk management functions, internal controls, and governance processes.

OurThe ERM Committee which is comprised of members of ourS&T executive leadership, including the CRO, CEO, President, Chief Financial Officer, Chief Credit Officer, Chief Commercial Banking Officer, Chief Human Resources Officer, Chief Operating Officer, Chief Audit Executive (“CAE”), Director of Consumer and Business Banking, Chief Information and Technology Officer, and General Counsel,Counsel. The ERM Committee meets at least quarterly to take the following actions prior to presentation to the Risk Committee: discuss the risk exposures of the enterprise, reviewsreview changes to those exposures based on internal and external events, takes action to manage and mitigate such risks, discussesand discuss significant policy changes, new products/products and services, model risk management reviews and ERM reports before presentation to the Riskreports. The ERM Committee and promotes proper risk management practices throughout S&T. A corporate policy approved by the Risk Committee governs the ERM Committee. The ERM Committee also operates pursuant to a written charter that is formally approved by the Risk Committee.

Pursuant to our Risk Committee charter, the CRO reports directly to the CEO, but has direct access to the Risk Committee, without impediment, and provides regular communication to the Risk Committee regarding risk management and regulatory compliance activities and other matters as the CRO determines necessary. The Risk Committee reviews and approves the appointment, replacement or dismissal of the CRO and oversees CRO succession planning.

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Corporate Governance

The CRO, as the administrator of the ERM program, regularly meets with management, including the CEO, to discuss the primary areas of risk identified above as part of the ERM program. As necessary, the Risk Committee meets with the CRO to discuss and analyze risks to S&T without management present.

The Audit Committee is responsible for oversight of financial risk, including internal controls which encompasses disclosure controls and procedures, and for the oversight of all trust activities consistent with the Federal Deposit Insurance Corporation’s Statement of Principles of Trust Department Management. The Audit Committee annually reviews and evaluates our internal audit function, and at least quarterly or as needed meets with our CAE to review and assess internal audit risks including during executive sessions without management present. The Audit Committee reviews and approves the appointment, replacement, or dismissal of the CAE, and reviews with the CAE the plans, activities, staffing, and organizational structure of the Audit and Advisory Services Department. The Audit Committee meets twice quarterly or as often as it determines is necessary and appropriate.

The Compensation and Benefits Committee (“Compensation Committee”) is responsible for assessing and mitigating risks associated with S&T’s human capital and compensation practices, both with respect to S&T’s NEOs (as further described in the Compensation Discussion and Analysis (“CD&A”) section of this Proxy Statement) and its employees generally. The Compensation Committee reviews the incentive compensation arrangements for S&T’s NEOs with the CRO at least annually to discuss and evaluate the risk posed to S&T by its employee compensation plans and to ensure that the compensation arrangements do not encourage the NEOs to take unnecessary and excessive risks that threaten the value of S&T. The Compensation Committee meets quarterly or as often as it determines is necessary and appropriate.

Our Credit Risk Committee is responsible for reviewing the credit administration risk management practices and reporting; the performance of the independent credit risk review function and its assessment of the management of credit risk arising from the lending and lending-related functions of S&T; the review of commercial lending activity, including portfolio reviews; the credit policy approval; and providing guidance on pertinent credit risk matters including loan-related strategies.

The Credit Risk Committee meets quarterly or as often as it determines is necessary and appropriate. The Credit Risk Committee reviews and approves the appointment, replacement, or dismissal of the Director of Credit Risk Review and at least annually reviews with the Director of Credit Risk Review the plans, activities, staffing and organizational structure of the credit risk review function. At least quarterly or as needed, the Credit Risk Committee meets with the Director of Credit Risk Review to discuss and analyze credit risks to S&T without management present.

The Executive Committee is responsible for exercising the authority to act on behalf of the S&T Board between meetings of the S&T Board to the fullest extent permitted by law. The Executive Committee meets as often as it determines is necessary and appropriate. Christina A. Cassotis, Jeffrey D. Grube, William J. Hieb, Christopher J. McComish, Frank J. Palermo, Jr., Christine J. Toretti (Chairperson) and Steven J. Weingarten serve as members of the Executive Committee.

Employee Compensation Policies and Managing Risk

We believe our approach to goal setting, setting of targets with payouts at multiple levels of performance, and evaluation of performance results assists in mitigating excessive risk taking that could harm our value or reward poor judgment by our executives. We believe that several features of our compensation policies and programs reflect sound risk management practices, such as basing incentive awards on the achievement of a predetermined earnings per share (“EPS”) goal, an, pre-provision net revenue and non-performing asset goals, all audited number,numbers, and granting restricted awards subject to a three year tiered time or three year cliff performance vesting that serves the additional purposes of encouraging senior management to make current decisions that promote long-term growth, promoting retention of senior management and encouragingrequiring senior management to meet stock ownership guidelines. All awards granted under S&T Bancorp, Inc.’s 2021 Incentive Plan (the “2021 Incentive Plan”) were subject to Compensation Committee review and approval based upon corporate and/or individual performance.

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Corporate Governance

The incentive plan for senior management, as described in the CD&A section below, contains a “Minimum Gateway Requirement” (other than for time-based awards) and a “Shareholder Protection Feature,” which provide that awards will not be made unless S&T achieves a Return on Average Equity of at least 5% and maintains well capitalized capital ratio requirements, as established by applicable regulatory authorities, respectively. We believe we have allocated our compensation among base salary and short and long-term compensation target opportunities in such a way as to not encourage excessive risk-taking. The Compensation Committee also reviews compensation and benefits plans affecting employees in addition to those applicable to executive officers. Based on the review by the Compensation Committee, the S&T Board determined that it is not reasonably likely that S&T’s compensation and benefit plans would have a material adverse effect on S&T.

Audit Committee

The members of the Audit Committee are Peter R. Barsz, Christina A. Cassotis, Jeffrey D. Grube, and Frank J. Palermo, Jr. (Chairperson). All members meet the independence standards for audit committees established by the SEC and NASDAQ. A written charter approved by the S&T Board governs the Audit Committee and complies with current NASDAQ Rules relating to charters and corporate governance. The Audit Committee reviews the adequacy of this charter annually and recommends any proposed changes to the S&T Board. A copy of the charter is included on S&T’s website www.stbancorp.com, under Governance. The Audit Committee has provided information regarding the functions performed by the Audit Committee and its membership in the “Report of the Audit Committee,” included in this Proxy Statement on page 67.66.

The Board has determined that Frank J. Palermo, Jr., CPA, Chair of the Audit Committee and Peter R. Barsz, CPA each qualify as an “audit committee financial expert” as defined in regulations issued pursuant to the Sarbanes-Oxley Act of 2002. The Audit Committee annually reviews the independent registered public accounting firm’s performance and independence in deciding whether to retain the firm or engage a different independent registered public accounting firm. As part of this review, the Audit Committee considers, among other things, the following:

The Audit Committee has the authority to consult with outside advisors as it deems necessary or appropriate to discharge its duties and responsibilities.

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Corporate Governance

Compensation and Benefits Committee

The members of the Compensation Committee are Peter R. Barsz, Christina A. Cassotis (Chairperson), Michael J. Donnelly, Jeffrey D. Grube, and Steven J. Weingarten. The Compensation Committee’s primary function is to recommend to the S&T Board action on executive compensation and compensation and benefit changes brought to it by management. A written charter approved by the S&T Board governs the Compensation Committee and complies with current NASDAQ Rules relating to charters and corporate governance. The Compensation Committee reviews the adequacy of this charter annually and recommends any proposed changes to the S&T Board. A copy of the charter is included on S&T’s website www.stbancorp.com, under Governance. The Compensation Committee is comprised entirely of independent board members, as defined by NASDAQ listing standards.

The Compensation Committee is responsible for our stated compensation strategies, goals and purposes, ensuring that there is a strong link between the economic interests of management and shareholders; that members of management are rewarded appropriately for their contributions to company growth and profitability; that the executive compensation strategy supports organization objectives and shareholder interests; and that human capital programs and policies, including with respect to management development, succession planning and diversity and inclusion initiatives are effective. The Compensation Committee must provide clear direction to management to ensure that its policies and procedures are carried out in a manner that achieves balance and is consistent with safety and soundness. It approves any material exceptions or adjustments to the incentive compensation arrangements established for senior management, and carefully considers and monitors the effects of any approved exceptions or adjustments. In support of the Compensation Committee’s responsibilities, S&T has an Incentive Compensation Steering Committee (“Steering Committee”), which operates under a formal management committee charter and whose members consist of the CEO, the President, the Chief Financial Officer, the CRO, the Chief Human Resource Officer, the Chief Operating Officer and any other officer that the Compensation Committee deems appropriate. The Steering Committee reviews all incentive plans to ensure that they are equitable across all business lines, tie to organizational goals, do not encourage excessive risk-taking and are not designed to incentivize conduct that violates law. As part of the Steering Committee’s responsibilities, it applies the safety and soundness guidelines established in our formal Incentive Compensation Arrangements policy.

The Compensation Committee receives and reviews, on an annual or more frequent basis, an assessment by management, with appropriate input from risk management personnel, of the effectiveness of the design and operation of the organization’s incentive compensation system in providing appropriate risk-taking incentives. It also reviews periodic reports of incentive compensation awards and payments relative to risk outcomes. It ensures that the incentive compensation arrangements for S&T do not encourage employees to take risks that are beyond S&T’s ability to manage effectively. It also performs other related duties as set forth in its written charter.

The process, policies and specific determinations of the Compensation Committee with respect to compensation of our NEOs for fiscal 2022,2023, including management’s role in such process, are described in greater detail in the CD&A section of this Proxy Statement.

The Compensation and Benefits Committee Report is on page 44 of this Proxy Statement.

The Compensation Committee has the authority to consult with outside advisors as it deems necessary or appropriate to discharge its duties and responsibilities.

Nominating and Corporate Governance Committee

The members of the Nominating Committee are Lewis W. Adkins, Jr., Peter R. Barsz, Frank J. Palermo, Jr. and Steven J. Weingarten (Chairperson). The Nominating Committee’s functions areGiven Mr. Weingarten intends to assistretire from the S&T Board in annually reviewingeffective upon the qualifications and independenceexpiration of his term immediately following the membersannual meeting, the Board will consider the subject of Nominating Committee chairpersonship at the S&T Board and its variousBoard’s annual reorganizational meeting following the Annual Meeting.

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Corporate Governance

The Nominating Committee’s functions are to assist the Board in annually reviewing the qualifications and independence of the members of the Board and its various committees as well as the composition and structure of the S&T Board; to review and make recommendations to the S&T Board as to its committee structure, functions and composition on a periodic basis; to oversee the annual assessment of the performance of the S&T Board, its committees and its directors, including whether its committees are functioning effectively; to recommend director nominees to the S&T Board to submit for election by shareholders; and to provide guidance to the S&T Board on corporate governance issues. Prior to beginning the annual assessment of the S&T Board and its committees, the Nominating Committee considers possible enhancements to the process to ensure continued effectiveness. Any feedback on the assessment process from the prior year is incorporated. During 2022, the Nominating Committee, with assistance and input from the Board Chairperson, enhanced its assessment process to make it more robust and to include three separate assessments, an S&Ta Board self-assessment, a committee self-assessment that is specific to each committee and an individual director self-assessment. The results of the S&T Board and committee self-assessments are reviewed by the Chair of the Nominating Committee and the Board Chairperson, then shared, reviewed and discussed with the entire Nominating Committee. To encourage candor, the individual director self-assessments are shared only with the Chair of the Nominating Committee and the Board Chairperson. The Chair of the Nominating Committee and the Board Chairperson, individually or together, may hold one-on-one discussions with individual directors to further discuss the S&T Board, committee and individual director self-assessments. The self-assessments pay particular attention to the S&T Board’s oversight of our risk management framework, S&T Board refreshment, the structure of the S&T Board and its committees and the S&T Board’s ability to take actions and make decisions efficiently and independently from management.

In addition, the Nominating Committee reviews all transactions with related parties, as further described on page 6463 of this Proxy Statement. The Nominating Committee oversees the S&T Director Orientation Program and the continuing education programs for all directors. To assist in remaining current with their board duties and committee responsibilities, the S&T Board participates in the Bank Directors’ Membership Program. This program offers the directors access to the BankDirector.com online video training series, a wide range of in-person conferences, periodic hard copy and digital magazines, and peer-based and webinar educational programs on corporate governance, risk management, committee duties, board leadership and industry developments. Various other educational opportunities and sources are also provided to the Board.

A written charter approved by the S&T Board governs the Nominating Committee and complies with current NASDAQ Rules relating to charters and corporate governance. The Nominating Committee reviews and reassesses the adequacy of this charter annually and recommends any proposed changes to the S&T Board. A copy of the charter is included on S&T’s website www.stbancorp.com, under Governance. The Nominating Committee is comprised entirely of independent board members, as defined by NASDAQ listing standards.

The Nominating Committee has the authority to consult with outside advisors as it deems necessary or appropriate to discharge its duties and responsibilities.

Director Qualifications and Nominations; Board Diversity

The Nominating Committee has adopted, and the S&T Board has ratified, a corporate policy for identifying and evaluating candidates for membership on the S&T, Board. The Nominating Committee identifies potential candidates based on suggestions from directors, officers of S&T, and S&T shareholders. An S&T shareholder may make a director nomination in accordance with Section 202 of S&T’s By-laws and applicable law. The procedure under Section 105 of the By-laws provides that a notice relating to the nomination must be timely given in writing to the Secretary of S&T, at 800 Philadelphia Street, Indiana, Pennsylvania 15701, prior to the annual meeting. To be timely, the notice must be delivered not earlier than the close of business on the 120th day (January 17, 2024)14, 2025), nor later than the close of business on the 90th day (February 16, 2024)13, 2025), prior to the first anniversary of the preceding year’s annual meeting (May 16, 2024)14, 2025), unless the date of the annual meeting is more than 30 days before or more than 60 days after such anniversary date, in which case we will notify you of

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Corporate Governance

the new deadlines. Among other requirements, such notice must be accompanied by the nominee’s written consent to be named in the applicable proxy statement and contain information relating to the business experience and background of the nominee and the nominee’s holdings of S&T Common Stock and information

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Corporate Governance

The Nominating Committee may engage a third-party search firm to assist it in identifying director candidates and did so in 2022.2023. The Nominating Committee includes a focus on diversity in its engagement letters with such firms. S&T did not receive any timely shareholder nominations for a director for consideration for this Annual Meeting.

Shareholder Communications with Directors

Shareholders who desire to communicate with the S&T Board or a specific director should send any communication, in writing, to S&T Bancorp, Inc., 800 Philadelphia Street, Indiana, Pennsylvania 15701, Attention: Secretary. Any such communication should state the number of shares beneficially owned by the shareholder. S&T’s Secretary will initially review all communications received in accordance with the Shareholders Communication Policy adopted by the S&T Board. The Secretary will relay all such communications to the appropriate director or directors on a periodic basis unless the Secretary determines that the communication does not relate to the business or affairs of S&T or the functioning or constitution of the S&T Board or any of its committees; relates to routine or insignificant matters that do not warrant the attention of the S&T Board; is an advertisement or other commercial solicitation or communication; is frivolous or offensive; or is otherwise not appropriate for delivery to directors. The director or directors who receive any such communication will have discretion to determine whether the subject matter of the communication should be brought to the attention of the full S&T Board or one or more of its committees and whether any response to the person sending the communication is appropriate. Any such response will be made through S&T’s management and only in accordance with S&T’s policies and procedures and applicable laws and regulations relating to the disclosure of information. If the Secretary believes the communication may be a complaint relating to any questionable accounting, internal accounting controls or auditing matter (“Covered Matter”), the Covered Matter will be handled in accordance with S&T’s Complaints Regarding Accounting, Internal Accounting Controls or Auditing Matters Policy (“Whistleblower Policy”). A copy of the Whistleblower Policy is included on S&T’s website www.stbancorp.com, under Governance.

Code of Conduct and Ethics

The S&T Board has adopted a General Code of Conduct for directors, officers, and employees and has further adopted a Code of Conduct for the (CEO) and Chief Financial Officer (“CFO”) (the “Senior Officer Code”, which contains additional provisions separate from the General Code of Conduct applicable to our Chief Executive Officer (CEO) and Chief Financial Officer (CFO)). Both the General Code of Conduct and the Senior Officer Code are posted on S&T’s website www.stbancorp.com, under Governance. The General Code of Conduct addresses the professional, honest and candid conduct of each director, officer and employee; conflicts of interest, disclosure process, and compliance with laws, rules and regulations (including insider trading laws); corporate opportunities, confidentiality, self-dealing and fair dealing; and protection and proper use of company assets. It also encourages reporting any illegal or unethical behavior. The Senior Officer Code addresses the CEO and CFOs duty to report certain significant deficiencies in S&T’s internal control over financial reporting or fraud involving financial reporting, disclosures, or internal control over financial reporting and other violations of laws. A waiver of the General Code of Conduct for an executive officer or director of S&T (or a waiver of the Senior Officer Code for the CEO or CFO) may be made only by the S&T Board and must be promptly disclosed as required by SEC or NASDAQ rules. S&T will disclose any such waivers, as well as any amendments to the General Code of Conduct or the Senior Officer Code, on S&T’s website. Shareholders may obtain a printed copy of the Code of Conduct or the Senior Officer Code by contacting the Secretary at the address previously provided.

Political Activity/Contributions

S&T recognizes the inherent risks and responsibilities of good citizenship. Employees are encouraged to take part in political activities on their own time and in their own name, so long as their participation does not affect their job performance; however, employees may not solicit campaign funds or engage in other forms of electioneering on business premises. S&T generally refrains from making contributions of anything of value to directly/directly or indirectly influence an election for political office. This includes the use of company facilities and equipment,

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Corporate Governance

equipment, loan of employees, loan or advances (other than under normal credit standards), furnishing of transportation, or special duplicating services. In the past fiscal year, S&T has spent no money and contributed nothing of value for political advocacy.

Employee, Officer and Director Hedging

Directors, officers, and employees are prohibited from engaging in any hedging transactions (including transactions involving options, puts, calls, prepaid variable forward contracts, equity swaps, collars and exchange funds, or other derivatives) that are designed to hedge or speculate on any change in the market value of S&T’s securities.

Compensation Committee Interlocks and Insider Participation

No member of the Compensation Committee was at any time during fiscal 20222023 an officer or employee of S&T or any of our subsidiaries, and no member has ever served as an officer of S&T. None of our executive officers

serves or, during fiscal year 2022,2023, served as a member of the board of directors or the compensation committee of any entity that has one or more executive officers serving as a member of the S&T Board or Compensation Committee.

Compensation Consulting and Advisory Services Fees

In 2022,2023, Aon plc (“Aon”) performed services for the Compensation Committee with respect to recommendations for the appropriate compensation level for the President and CEO; for evaluation of and recommendations for S&T’s peer banks; for an analysis of S&T’s executive compensation, including the NEOs, compared with S&T’s peer banks; and for refinements to the Management Incentive Plan and Long-Term Incentive Plan.

In 2022,2023, the Compensation Committee reviewed and assessed the independence of Aon and concluded that Aon’s work did not raise any conflicts of interest and that they are independent. In reaching these conclusions, the Compensation Committee considered the factors set forth in the SEC rules and NASDAQ listing standards.

Environmental, Social and Governance Practices

S&T’s 20222023 Corporate Responsibility Report provides S&T’s environmental, social and governance practices and can be found at https://www.stbank.com/corporateresponsibility.

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DIRECTOR COMPENSATION

The Nominating Committee annually reviews S&T’s director compensation and makes recommendations to the Board. S&T’s director compensation is designed to align the S&T Board with its shareholders and to attract, motivate and retain high performing members critical to S&T’s success. A directors’ compensation analysis including a peer comparison is completed annually. The objective is to evaluate our director compensation against our peer group to ensure S&T’s compensation practices for our directors are consistent with banks our size and within similar markets. S&T uses a combination of cash and restricted units to attract and retain qualified candidates to serve on the Board. Restricted stock grants are intended to align directors’ interests with those of S&T’s shareholders.

In 2022,2023, our non-employee directors received compensation for serving on the S&T Board and attending Board and committee meetings, or educational seminars, in the amounts described below. Employee members of the S&T Board receive no additional compensation for participation on the S&T Board. We reimbursed various directors for amounts expended for traveling to our meetings and to educational seminars. We determined these amounts were consistent with our guidelines and thus are not included in the 20222023 Director Compensation table.

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Director Compensation

The following table provides information concerning compensation paid by S&T to its non-employee directors during 2022.2023.

Director Compensation Table for Fiscal Year 20222023

Directors’ Stock Ownership

The Board has adopted stock ownership guidelines for the directors of S&T. The guidelines require each director to own at least $100,000 in market value of Common Stock within one year of being elected to the Board in order to be nominated for reelection as a continuing director candidate for a second or third term of service. To be nominated for reelection as a continuing member of the Board for a fourth, or more, term of service, such continuing director candidate must own at least $250,000 in market value of the Common Stock. Each of our directors other than Mr. Adkins, satisfied the stock ownership guidelines as of January 25, 2023,24, 2024, the date of nomination. In the case of Mr. Adkins, the Board decided to grant a one-time exception to the guidelines given Mr. Adkins’s holdings of $204,236 on such date, his longstanding compliance with the guidelines, and his agreement to meet the guidelines no later than May 31, 2023.

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PROPOSAL 2: RATIFICATION OF THE SELECTION OF INDEPENDENT REGISTERED

PUBLIC ACCOUNTING FIRM FOR FISCAL YEAR 20232024

The Audit Committee of the S&T Board appointed the firm of Ernst & Young LLP (Ernst & Young) as its independent registered public accounting firm (“Independent Accountants”), to audit and report on S&T’s financial statements for the fiscal year ending December 31, 2023.2024. The S&T Board now recommends that S&T’s shareholders ratify this appointment.

We are not required to have the shareholders ratify the selection of Ernst & Young as our independent registered public accounting firm. We are doing so because we believe it is a matter of good corporate practice. If the shareholders do not ratify the selection, the Audit Committee will reconsider whether or not to retain Ernst & Young but may nevertheless decide to continue to retain such independent registered public accounting firm. Even if the selection is ratified, the Audit Committee, in its discretion, may change the appointment at any time during the year if it determines that such change would be in the best interests of S&T and its shareholders.

Ernst & Young has no direct or indirect financial interest in S&T or in any of its subsidiaries, nor has it had any connection with S&T or any of its subsidiaries in the capacity of promoter, underwriter, voting trustee, director, officer, or employee. Representatives of Ernst & Young are expected to be present at the virtual Annual Meeting and will be afforded an opportunity to make a statement if they desire to do so. It is also expected they will be available to respond to appropriate questions.

Fees Paid to Independent Registered Public Accounting Firm

The financial statements of S&T are audited annually by an independent registered public accounting firm. For the fiscal years ended December 31, 20222023 and December 31, 2021,2022, the audit was performed by Ernst & Young. Fees for professional services provided by Ernst & Young in each of the last two fiscal years are summarized below:

“Audit Fees” for 20222023 and 20212022 include fees for audit services associated with the annual audit, the reviews of S&T’s quarterly reports on Form 10-Q, accounting, consultations, and SEC registration statements.

“Audit-Related Fees” for 20222023 and 20212022 include fees billed for U.S. Department of Housing and Urban Development compliance procedures.

“Tax Fees” include fees for tax compliance work for the Wealth Management division for client fiduciary tax returns performed in 20222023 and 2021.2022.

There were no “All Other Fees” for 20222023 and 2021.2022.

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Proposal 2: Ratification of the Selection of Independent Registered

Public Accounting Firm For Fiscal Year 20232024

Pre-Approval Policies and Procedures

The Audit Committee is responsible for the approval of all services performed by S&T’s independent registered accounting firm. All services provided by Ernst & Young in 20222023 were pre-approved by the Audit Committee. The Audit Committee is required to pre-approve all audit and non-audit services performed by the

Independent Accountants to assure that the provision of such services does not impair the Independent Accountant’s independence. In addition, any proposed services exceeding pre-approved cost levels will require specific pre-approval by the Audit Committee. The Audit Committee may delegate pre-approval authority to one or more of its members. The member or members to whom such authority is delegated will report any pre-approval decisions to the Audit Committee at its next scheduled meeting for ratification. The Audit Committee does not delegate its responsibilities to pre-approve services performed by the Independent Accountants to management.

Board Recommendation

THE S&T BOARD RECOMMENDS A VOTE “FOR” FOR RATIFICATION OF THE SELECTION OF ERNST & YOUNG LLP AS S&T’s INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR FISCAL YEAR 2023.2024.

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PROPOSAL 3: ADVISORY VOTE TO APPROVE COMPENSATION

OF S&T’S NAMED EXECUTIVE OFFICERS

S&T believes that our overall executive compensation program, as described in the “Compensation Discussion and Analysis” section elsewhere in this Proxy Statement, is designed to pay for performance and directly aligns the interest of our executive officers with the long-term interests of our shareholders.

As required by Section 14A of the Exchange Act, S&T is providing its shareholders a vote to approve, on a non-binding advisory basis, the compensation of our NEOs as disclosed in this Proxy Statement in accordance with the SEC’s rules. This vote is not intended to address any specific item of compensation or the compensation of any particular officer, but rather the overall compensation of our NEOs and our compensation philosophy, policies, and practices. Pursuant to Section 14A of the Exchange Act, the S&T Board recommended, and the shareholders subsequently approved on an advisory basis at the 2018 annual meeting of shareholders, that this advisory proposal on executive compensation be submitted to shareholders annually. This year, S&T expects&T’s shareholders will again be asked to hold the next advisory vote onapprove the frequency of the advisory vote on compensationexecutive compensation. See Proposal 4 below. Assuming the shareholders approve the frequency of one year, in accordance with the Board’s recommendation, the next advisory vote will occur at thenext year’s annual meeting of shareholders in 2024.shareholders.

Accordingly, S&T is presenting the following advisory proposal, commonly known as the “say-on-pay proposal,” for shareholder approval:

“Resolved, that the shareholders hereby approve, on a non-binding basis, the compensation of our Named Executive Officers as disclosed in this Proxy Statement pursuant to Item 402 of Regulation S-K, which disclosure includes the compensation discussion and analysis, the compensation tables and all related material.”

Because your vote is advisory, it will not be binding upon the S&T Board. In the event this proposal is not approved by our shareholders, it will not be construed as overruling a decision by the S&T Board or the Compensation Committee, nor create or imply any additional fiduciary duty by the S&T Board or our Compensation Committee, nor will it be construed to restrict or limit the ability of our shareholders to make proposals for inclusion in proxy materials related to executive compensation. Notwithstanding the foregoing, the S&T Board and the Compensation Committee will consider the non-binding vote of our shareholders on this proposal when reviewing compensation policies and practices in the future.

Board Recommendation

THE S&T BOARD RECOMMENDS A VOTE “FOR” THE APPROVAL OF THE COMPENSATION OF S&T’s NAMED EXECUTIVE OFFICERS.

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PROPOSAL 4: ADVISORY VOTE ON FREQUENCY

OF FUTURE ADVISORY VOTES ON EXECUTIVE COMPENSATION

As described in Proposal 3 above, S&T’s shareholders have the opportunity to cast an advisory vote on the compensation of S&T’s NEOs’ compensation as disclosed in this Proxy Statement. Section 14A of the Exchange Act also enables our shareholders to indicate how frequently we should seek an advisory vote on the compensation of our NEOs.

Our shareholders last voted in 2018 for the right to cast an advisory vote on the compensation of S&T’s named executive officers every year, consistent with the Board’s recommendation. This year, we are again asking shareholders to vote to indicate whether they would prefer holding an advisory vote on executive compensation every one, two or three years. Shareholders who have no preference may also abstain from voting.

S&T’s Board continues to recommend that an advisory vote be conducted every year so that shareholders may provide timely, direct input on S&T’s executive compensation program as disclosed in the proxy statement each year, which is consistent with our efforts to engage in an ongoing dialogue with our shareholders regarding executive compensation.

This vote is advisory and not binding on S&T, our Compensation Committee, or the Board. However, the Board and the Compensation Committee value the opinions expressed by the shareholders and will consider the outcome of the vote when considering the frequency of future advisory votes on executive compensation.

Board Recommendation

THE S&T BOARD RECOMMENDS A VOTE FOR A FREQUENCY OF “ONE YEAR” FOR FUTURE ADVISORY VOTES ON THE COMPENSATION OF S&T’S NAMED EXECUTIVE OFFICERS

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EXECUTIVE OFFICERS OF THE REGISTRANT

Each executive officer of S&T holds office for the current year for which he or she was elected or appointed by the Board unless he or she resigns, becomes disqualified or is removed in the discretion of the S&T Board. The current executive officers of S&T and S&T Bank are:

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COMPENSATION DISCUSSION AND ANALYSIS

INTRODUCTION

We provide the following overview of S&T’s executive compensation principles, specific executive compensation programs, and pay decisions that were made by the Compensation Committee in 2022.2023. In addition, we describe the process by which we arrive at specific compensation policies and decisions involving program design and pay for S&T’s NEOs, who are listed below.

EXECUTIVE SUMMARY

Key Business and Financial Highlights

As reported in S&T’s Form 10-K for the year ended December 31, 2022,2023, we are pleased to report^(*)*:

Key 20222023 Compensation Decisions

For 2022,2023, the Compensation Committee evaluated and approved the following adjustments and awards for our NEOs:

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Compensation Discussion and Analysis

SAY ON PAY AND SHAREHOLDER ENGAGEMENT

S&T is required to provide a separate non-binding shareholder advisory vote on the compensation of S&T’s NEOs. At the 20222023 annual meeting of shareholders, the holders of 25,678,73126,633,530 shares of Common Stock, or 94%96% of the shares voting on the proposal, voted to approve the non-binding, advisory proposal on the compensation of S&T’s executive officers.

The Compensation Committee believes the results of this vote demonstrate the strong support for S&T’s executive compensation policies and practices among shareholders. The Compensation Committee expects to continue to adhere to the compensation policies, principles and programs described below in future years, and will continue to consider these non-binding advisory results on our compensation programs, among other factors.

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Compensation Discussion and Analysis

OVERVIEW OF THE COMPENSATION PROGRAM, POLICIES AND PROCESS

Executive Compensation Philosophy and Practices

S&T designs its management compensation programs and policies to optimize their alignment with S&T’s strategic direction and business environment within which it must create value for shareholders and focus on pay for performance. Listed below are some of S&T’s primary program objectives, practices, and policies.

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Compensation Discussion and Analysis

Compensation Approval Process

Our Compensation Committee engages with management and an independent compensation consultant as a part of its processes – the role of each and the overall compensation approval process are described in greater detail below.

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Compensation Discussion and Analysis

Use of Competitive Data

The Compensation Committee reviews comparisons of the compensation programs established by peer banks for executives having similar responsibilities to S&T’s executives to obtain a general understanding of current market practices to assist in evaluating S&T’s compensation program. In 2021,2023, the Compensation Committee engaged Aon to advise on the appropriateness of the banks in the peer group considering S&T’s current status and common practices among peer banking organizations for defining peer groups for executive compensation review purposes. The Compensation Committee reviewed and agreed with Aon’s recommendations and selected the following peer group based on similar size and scope to S&T and operating both inside and outside S&T’s geographic market (collectively, the “Peer Banks”):

The Peer Banks were used by Aon to analyze the total direct compensation for S&T’s executives for 2022 and will continue to be used in evaluating compensation for S&T executives, including the NEOs, going forward. Based on Aon’s analysis on the Peer Banks in 2022, the Compensation Committee removed TowneBank from the Peer Banks, due to its larger asset size and geography in comparison with S&T.

2023. The Compensation Committee uses the companies in the S&P 600 Bank Industry Index as of January 1 of the plan year (the “Performance Peer Group”) for comparing S&T’s relative performance for that year’s LTIP. The companies in the S&P 600 Bank Industry Index as of January 1, 20222023 are the Performance Peer Group for the 20222023 LTIP.

Total Direct Compensation Position

S&T’s target pay mix is built on competitive base salaries, with generally moderate annual and long-term incentive targets. The moderate positioning of annual incentives and long-term incentives reflects our commitment to introducing pay program modifications that are both sensitive to S&T’s proactive risk management culture while, at the same time, responding appropriately to the importance of retaining a strong and committed leadership team at S&T. The Compensation Committee reviews this posture periodically with the help of outside advisors.

For NEOs, the Compensation Committee reviews a number of analyses of compensation practices to help facilitate its executive compensation decisions. These include:

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Compensation Discussion and Analysis

COMPONENTS OF THE COMPENSATION PROGRAM

The Compensation Committee continues to support a pay program with five major components to help guide compensation decisions:

A detailed review of each of the above compensation components and the 20222023 decisions and payouts is provided in the sections below.

Base Salary

As described above, the purpose of base salary is to provide competitive and fair base compensation that recognizes the executives’ roles, responsibilities, contributions, experiences, and performance. The Compensation Committee independently decides the compensation that S&T will pay the CEO and President and, for the remaining executive officers, the CEO makes recommendations to the Compensation Committee, which reviews, approves or adjusts the recommendations. Each executive’s individual pay reflects individual experience, expertise, performance, and contributions in the role.

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Compensation Discussion and Analysis

20222023 Base Salary Amounts

When appropriate, the Compensation Committee increases base salaries both to ensure consistency with market competitive practices and to recognize the critical value of each senior executive’s management of S&T. The Compensation Committee decided to hold 20222023 salaries at the 20212022 level for Messrs. McComish and Antolik. The following table summarizes the 20222023 base salaries for each of our NEOs. Messrs. Kochvar and Drahnak and Ms. Yesho received a pay increase effective February 4, 2023, to align their pay as appropriate to their positions as related to peers.

Management Incentive Plan Awards

For 2022,2023, we adopted the 20222023 MIP, an annual cash incentive award with a target equal to a set percentage of base salary for each of our NEOs.

The following formula is used to determine MIP award payouts:

To further strengthen the linkage between the MIP award, risk management, and shareholder value creation, the MIP contains a “Shareholder Protection Feature” in which payouts will not occur for any plan year if S&T falls below “well capitalized” capital ratio requirements established by regulatory authorities, determined as of and up to the date that any payment would ordinarily occur pursuant to the MIP’s provisions. In addition to the Shareholder Protection Feature of the MIP, the MIP is operational only if S&T achieves Return on Average Equity (“ROAE”) for the plan year of at least 5% (the “Minimum Gateway Requirement”). The Compensation Committee believes that these features, coupled with the claw-back requirements and the use of multiple performance measures, provide for substantial protection against excessive or unnecessary risk-taking by any plan participant.

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Compensation Discussion and Analysis

Corporate Performance Factor

For the 20222023 fiscal year, we madecontinued with certain changes toaspects of our incentive compensation program to ensure S&T’s ability to recruit and retain top talent while further increasing the percentage of our NEO’s total direct compensation that is at-risk and tied to company performance metrics. 

Specifically, we revised ourthe annual MIP to expandcontinues in 2023 with the metrics from 2022 for the company performance factor. We retained EPS as a metric weighted at 60% but nowand also utilize pre-provision net revenue (“PPNR”) (20%) and asset quality (20%). We incorporate theThe PPNR ratio is incorporated to have a profitability measure which is neutral to the impact of asset quality and taxes. We also are focusingfocus on improving asset quality and include an asset quality metric (Non-performing(Non-performing Assets/Loans+Other Real Estate Owned) in the company performance factor. Because this provides a more holistic company performance review, we also removed the individual performance factor forwas removed in the 2022 MIP. Lastly, we increasedMIP and the target incentive opportunities as a percentage of salary to 50%exclusion was continued for the President and CFO and 40% for the other non-CEO NEOs. Mr. McComish, our CEO, has a target incentive opportunity of 67% pursuant to his employment agreement.2023.

The actual earnings opportunity was based on the performance level achieved relative to the performance ranges shown in the table below with a target EPS equal to $2.55;$4.00; PPNR of 1.46%2.35%; and asset quality of 0.47%0.41%. “Allocated Target” equals the participant’s MIP incentive target multiplied by the weighting for each performance category (e.g.(i.e., 60% for EPS, 20% for PPNR and 20% for asset quality).

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Compensation Discussion and Analysis

Based on achieving 171%81% of the Target Performance Level, the Compensation Committee approved the following cash awards under the 20222023 MIP to each NEO:

Long-Term Incentive Plan Awards

The LTIP is designed to: (1) to help promote leadership retention and management continuity as S&T continues to execute its longer-term strategic plan; (2) to reward management for strong sustained value creation and financial performance; and (3) to align our executives’ interests with those of our shareholders via appropriately-sized grants of equity compensation. The 20222023 LTIP puts a greater focus on performance and serves to create a balance between long-term and short-term performance imperatives, beyond that offered by the annual cash incentive under the MIP.

We madeThe changes to ourimplemented in 2022 were maintained in 2023 for the LTIP awards. We increased theThe target opportunities as a percentage of base salary toremained at 50% for the President and the CFO and to 40% for all other non-CEO NEOs. The CEO has a target opportunity of 100% in accordance with his employment agreement. For 2022 only, in accordance with his employment agreement, the President has an award at a value of $409,217 (71.67% of salary target opportunity) partially in recognition of his Interim CEO role in 2021. We also modified theThe Compensation Committee determined to keep payout levels on the peer-relative ROAE metric toat 50% of target (Threshold Performance), 100% of target (Target Performance) and 150% of target (Maximum Performance) and changed the peer-relative TSR to a modifier to the ROAE payout metric: -30% (Threshold or below), 0% (Target) and +30% (Maximum). The foundation similar to the 2021 LTIP approach with higher upside (195% versus 150%), and the symmetric Total Shareholder Return (“TSR”) modifier provides benefits or take-aways based upon S&T’s performance. The 2021 approach did not have a downside for poor performance on TSR. We consider the enhanced upside on the ROAE payout metric combined with the TSR modifier to offer a long-term incentive that better aligns the interests of NEOs with shareholders. Lastly, our 20222023 time-based restricted sharesawards are scheduled to vest pro rata annually over three years rather than 50% on each of the second and third anniversaries ofafter the grant date.

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Compensation Discussion and Analysis

Time-based units vest in equal amounts on each anniversary of their grant date over three years. Performance-based units (“PRSUs”) may be earned over a three-year period based on the Company’s Return on Average Equity (“ROAE”) and Total Shareholder Return (“TSR”) performance relative to the Performance Peer Group (defined in “Use of Competitive Data” on page 35)36), as described in more detail below.

The following awards were granted under the 20222023 LTIP to the NEOs:

20222023 LTIP Performance Metrics

Two metrics are used to determine the percentage of the PRSU target earned through vesting of the PRSU awards (also referred to as performance shares). The Compensation Committee believes that ROAE measures and incentivizes S&T’s long-term profitability vis-à-vis our peers, while our relative TSR captures our shareholder return vis-à-vis our peers.

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Compensation Discussion and Analysis

The Modifier will vary depending on Actual Performance, and the payout curve rises continuously from Threshold to Target and from Target to Maximum. Therefore, to determine awards between Threshold and Target and Target and Maximum, linear interpolation would be utilized.

Vesting of 20192020 Long-Term Incentive Plan Awards

Because S&T was below the 50th percentile for 3 Year ROAE and below the 50^th percentile for TSR relative to the peer banks identified at the time of grant, the NEOs’ performance-based shares granted on April 1, 20192020 did not vest and were forfeited in 2022.2023. The Committee approved the vesting of the time-based awards based on S&T meeting the Shareholder Protection Feature.

Certain Other Benefits

S&T provides certain other benefits to the NEOs that are appropriately limited in scope and value. The primary benefits for the NEOs are a broad-based defined contribution retirement plan and welfare benefit plan, a nonqualified deferred compensation plan, and a defined benefit program. The Thrift Plan for Employees of S&T Bank (the “Thrift Plan”) is a broad-based qualified defined contribution plan. All employees may participate in the Thrift Plan with elective salary deferrals, or 401(k) contributions. During 2022,2023, S&T made matching contributions equal to 100% of the first 1% of the employees’ eligible compensation and 50% of the next 5% of the employees’ eligible compensation, up to a maximum of 3.5% of all employees’ eligible compensation. More information regarding the other retirement benefits can be found beginning on page 50. The S&T Bank Welfare Benefit Plan is generally provided to all officers and full-time employees and includes provisions for medical reimbursement, dental coverage, vision care coverage, long-term disability income, a flexible spending account, a health savings account, and life insurance.

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Compensation Discussion and Analysis

OTHER COMPENSATION-RELATED PROVISIONS

Mitigation in Plan Design Risk

The Compensation Committee considers, in establishing and reviewing the executive compensation program, whether the program encourages any unnecessary or excessive risk taking and concludes:

In addition, at least annually, the Compensation Committee discusses, evaluates and reviews with S&T’s CRO the compensation arrangements to ensure that: (i) the compensation plans for senior management (senior vice presidents or higher) do not encourage the members of senior management to take unnecessary and excessive risks that threaten the value of S&T, (ii) the compensation plans for employees do not pose unnecessary risks to S&T, and (iii) the compensation plans for employees do not encourage the manipulation of reported earnings to enhance the compensation of any of S&T’s employees.

Employment Agreements

S&T provided employment agreements to Messrs. McComish and Antolik for their roles as CEO and President, respectively, on July 12, 2021. S&T does not provide employment agreements for any of the other NEOs. For more detail regarding the employment agreements for Messrs. McComish and Antolik see further discussion in Additional Narrative Information – Compensation Agreements on page 47.

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COMPENSATION AND BENEFITS COMMITTEE REPORT

We, the Compensation and Benefits Committee of the Board of Directors of S&T Bancorp, Inc. (“S&T”), have reviewed and discussed the Compensation Discussion and Analysis included in this Proxy Statement with S&T’s management, and, based on such review and discussion, have recommended to the Board of Directors that the Compensation Discussion and Analysis be included in this Proxy Statement and S&T’s Annual Report on Form 10-K for the year ended December 31, 2022.Statement.

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EXECUTIVE COMPENSATION

The following table provides information concerning remuneration of the NEOs during 2020-2022.2021-2023.

Summary Compensation Table