Proxy Statement (Form DEF 14A)

March 7, 2025

Dear Shareholder:

We cordially invite you to attend the 2025 Annual Meeting of Shareholders of Northwest Bancshares, Inc., the parent company of Northwest Bank. The Annual Meeting will be held virtually at 10:00 a.m., EasteTime on April 17, 2025. You will be able to access the Annual Meeting, vote and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/NWBI2025.

The enclosed Notice of Annual Meeting and Proxy Statement describe the formal business to be transacted. Our directors and officers, as well as a representative from our independent registered public accounting firm, will be available to respond to any questions that shareholders may have.

The business to be conducted at the Annual Meeting includes the election of four directors, the ratification of the appointment of KPMG LLP as the independent registered public accounting firm for the year ending December 31, 2025 and the consideration of an advisory, non-bindingresolution to approve the executive compensation described in the Proxy Statement.

Our Board of Directors has determined that the matters to be considered at the Annual Meeting are in the best interests of Northwest Bancshares, Inc. and its shareholders. For the reasons set forth in the Proxy Statement, the Board of Directors unanimously recommends a vote "FOR" each matter to be considered.

Under rules established by the Securities and Exchange Commission, we sent the majority of those shareholders who are eligible to vote at the Annual Meeting a notice that explains how to access their proxy materials, including our 2024 Annual Report, online, rather than in traditional printed form. The notice also explains the steps our eligible shareholders can follow in order to vote their shares via the Internet, mobile or by phone. If you are among the shareholders who received the notice explaining this process and would prefer to receive your proxy materials in printed format, the notice also explains how to arrange to have the printed materials sent to you in the mail. If you are among those who received their proxy materials in printed form, rather than the notice, please note that you may still access these materials and vote your shares online by going to the following website: www.proxyvote.com.

Please take a moment now to cast your vote via the Internet, mobile or by phone as described on your Proxy Card or your voting instruction card, or alternatively, complete, sign, date and retuthe Proxy Card in the postage-paid envelope provided. Voting in advance of the Annual Meeting will not prevent you from voting virtually during the Annual Meeting, but will assure that your vote is counted if you are unable to attend the Annual Meeting virtually.

Sincerely,

Louis J. Torchio

President and Chief Executive Officer

NORTHWEST BANCSHARES, INC.

3 Easton Oval, Suite 500

Columbus, Ohio 43219

(800) 859-1000

NOTICE OF

2025 ANNUAL MEETING OF SHAREHOLDERS

To Be Held On April 17, 2025

Notice is hereby given that the 2025 Annual Meeting of Shareholders of Northwest Bancshares, Inc. will be held virtually on April 17, 2025 at 10:00 a.m., EasteTime. You will be able to access the Annual Meeting, vote and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/NWBI2025.

A Proxy Card and a Proxy Statement for the Annual Meeting are enclosed.

The Annual Meeting is for the purpose of considering and acting upon:

such other matters as may properly come before the Annual Meeting, or any adjournments thereof. The Board of Directors is not aware of any other business to come before the Annual Meeting.

Any action may be taken on the foregoing proposals at the Annual Meeting on the date specified above, or on any date or dates to which the Annual Meeting may be adjourned. Shareholders of record at the close of business on February 18, 2025, are the shareholders entitled to vote at the Annual Meeting, and any adjournments thereof.

EVEN IF YOU PLAN TO ATTEND THE ANNUAL MEETING VIRTUALLY, YOU MAY CHOOSE TO VOTE YOUR SHARES USING THE INTERNET, MOBILE OR PHONE VOTING OPTIONS EXPLAINED ON YOUR PROXY CARD OR VOTING INSTRUCTION CARD OR BY SIGNING, DATING AND RETURNING THE ENCLOSED PROXY CARD WITHOUT DELAY IN THE ENCLOSED POSTAGE-PAID ENVELOPE. ANY PROXY THAT YOU GIVE MAY BE REVOKED AT ANY TIME BEFORE IT IS EXERCISED. YOU MAY REVOKE A PROXY BY FILING WITH THE CHIEF COUNSEL AND CORPORATE SECRETARY OF NORTHWEST BANCSHARES, INC. A WRITTEN REVOCATION OR A DULY EXECUTED PROXY BEARING A LATER DATE. IF YOU ATTEND THE ANNUAL MEETING VIRTUALLY, YOU MAY REVOKE YOUR PROXY AND VOTE ON EACH MATTER BROUGHT BEFORE THE MEETING. HOWEVER, IF YOUR SHARES ARE NOT REGISTERED IN YOUR NAME, YOU WILL NEED ADDITIONAL DOCUMENTATION FROM YOUR RECORD HOLDER TO VOTE VIRTUALLY DURING THE ANNUAL MEETING.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR

THE ANNUAL MEETING OF SHAREHOLDERS TO BE HELD ON APRIL 17, 2025

The Notice of Annual Meeting of Stockholders to be held on April 17, 2025, the accompanying Proxy Statement and Proxy Card and the Company's 2024 Annual Report on Form 10-Kare available, free of charge, at www.proxyvote.com. Shareholders who wish to receive a printed copy of the proxy materials available on this web site may request copies in any of the following ways: (i) via the Internet, at www.proxyvote.com; (ii) by phone, at 1-800-579-1639;or (iii) by sending an e-mailto [email protected].

Columbus, Ohio

March 7, 2025

NORTHWEST BANCSHARES, INC.

TABLE OF CONTENTS

Proxy Statement

NORTHWEST BANCSHARES, INC.

3 Easton Oval, Suite 500

Columbus, Ohio 43219

(800) 859-1000

2025 ANNUAL MEETING OF SHAREHOLDERS

April 17, 2025

This Proxy Statement is furnished in connection with the solicitation of proxies on behalf of the Board of Directors of Northwest Bancshares, Inc. (the "Company") to be used at the 2025 Annual Meeting of Shareholders of the Company (the "Annual Meeting"), which will be held virtually on April 17, 2025, at 10:00 a.m., EasteTime, and all postponements and adjournments of the Annual Meeting. The accompanying Notice of Annual Meeting of Shareholders and this Proxy Statement are first being mailed to shareholders on or about March 7, 2025. You will be able to access the Annual Meeting, vote and submit your questions during the meeting by visiting www.virtualshareholdermeeting.com/NWBI2025.

VOTING SECURITIES AND PRINCIPAL HOLDERS THEREOF

Holders of record of our shares of common stock, par value $0.01 per share (the "common stock"), as of the close of business on February 18, 2025 are entitled to one vote for each share then held. As of February 18, 2025, there were 127,514,858 shares of common stock issued and outstanding. The presence in person or by proxy of a majority of the outstanding shares of common stock entitled to vote is necessary to constitute a quorum at the Annual Meeting. Abstentions and broker non-voteswill be counted for purposes of determining that a quorum is present.

As to the election of directors, the Proxy Card being provided by the Board of Directors (also referred to herein as the "Board") enables a shareholder to authorize a proxy to vote "FOR" all nominees proposed by the Board, to withhold authority for all nominees or to vote for all except one or more of the nominees being proposed. Directors are elected by a plurality of votes cast, without regard to either broker non-votes,or proxies as to which the authority to vote for the nominees being proposed is withheld. In addition, the Company has adopted a policy regarding majority voting with respect to the election of directors, which requires any incumbent director nominee in an uncontested election who receives a greater number of votes "WITHHELD" than votes cast "FOR" at a shareholders' meeting to promptly tender his or her resignation following certification of the vote. For more information, see "Policy Regarding Majority Voting".

As to the ratification of KPMG LLP as our independent registered public accounting firm, by checking the appropriate box, a shareholder may authorize a proxy to: (i) vote "FOR" the ratification; (ii) vote "AGAINST" the ratification; or (iii) abstain from voting on such ratification. The affirmative vote of a majority of the votes cast at the Annual Meeting, without regard to abstentions, is required for the approval of this matter. As described in more detail below, this proposal is considered a routine matter, and therefore no broker non-votesare expected to exist in connection with the ratification of KPMG LLP as our independent registered public accounting firm.

As to the advisory, non-bindingresolution to approve our executive compensation as described in this Proxy Statement, a shareholder may authorize a proxy to: (i) vote "FOR" the resolution; (ii) vote "AGAINST" the resolution; or (iii) abstain from voting on the resolution. The affirmative vote of a majority of the votes cast at the Annual Meeting, without regard to either broker non-votes,or abstentions, is required for the approval of this non-bindingresolution. While this vote is required by law, it will neither be binding on the Company or the Board of Directors, nor will it create or imply any change in the fiduciary duties of, or impose any additional fiduciary duty on the Company or the Board of Directors.

As provided in Section D of Article 5 of our charter (the "Charter"), in no event shall the record owner (or if more than one record owner, all such record owners taken as a group) of any outstanding common stock that is beneficially owned, directly or indirectly, by a person who, as of the record date, beneficially owns in excess of 10% of the outstanding shares of our common stock (the "Limit"), be entitled, or permitted to any vote of shares held in excess of the Limit. The number of votes that may be cast by any particular record owner by virtue of this provision in respect of common stock beneficially owned by such person owning shares in excess of the Limit (a "Holder in Excess") shall be a number equal to the total number of votes that a single record owner of all common stock owned by such Holder in Excess would be entitled to cast after giving effect to this provision, multiplied by a fraction, the numerator of which is the number of shares of such class or series that are both (i) beneficially owned by such Holder in Excess and (ii) owned of record by such particular record owner and the denominator of which is the total number of shares of common stock beneficially owned by such Holder in Excess.

Subject to certain exceptions, a person is deemed to beneficially own shares owned by an affiliate of, as well as by persons with certain acquisition, holding, voting or disposition rights who are party to certain specified agreements, arrangements, or

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understandings with, such person. The Board of Directors is authorized to construe and apply the provisions of Section D of Article 5 of our Charter, and to make all determinations it deems necessary or desirable to implement them, including determining the number of shares beneficially owned by any person and whether a person is an affiliate of or has an arrangement or agreement with another person, and to demand certain information from any person who is reasonably believed to beneficially own stock in excess of the 10% limit and reimbursement for all expenses incurred by the Company in connection with an investigation conducted by the Board of Directors pursuant to the provisions of Article 5, Section D of our Charter.

If you hold shares in the Northwest Bank 2015 Amended and Restated 401(k) Plan, you will separately receive directions on how to submit your voting instructions. Northwest Bank, the 401(k) plan's trustee, must receive your voting instructions for the common stock held on your behalf in the 401(k) plan on or before April 14, 2025. If Northwest Bank does not receive your voting instructions by that date, it will vote such shares together with other unvoted, forfeited and unallocated shares in the 401(k) plan in the same proportion as the voting instructions that it receives from other participants in the 401(k) Plan. On February 18, 2025, there were 3,915,223 shares in the 401(k) plan.

If you have selected a broker or other intermediary to hold your common stock rather than having them directly registered with our transfer agent, Equiniti Trust Company, LLC, you will receive instructions directly from your broker or other intermediary in order to vote your shares. Your brokerage firm may also provide the ability to vote your proxy via the Internet, mobile or phone. Please be advised that if you choose to not vote your proxy, your brokerage firm only has the authority under applicable stock market rules to vote your shares in relation to routine matters. The ratification of the appointment of the independent registered public accounting firm is deemed to be a routine matter. Accordingly, we urge you to vote by following the instructions provided by your broker, bank, or other intermediary.

We are utilizing Securities and Exchange Commission rules that allow companies to furnish proxy materials to shareholders via the Internet. Accordingly, we are sending a Notice of Internet Availability of Proxy Materials ("Notice") to our shareholders of record and beneficial owners, unless they have directed us to provide the materials in a different manner or hold shares of our common stock through our stock-based benefit plans. The Notice provides instructions on how to access and review all of the information contained in the Company's Proxy Statement and Annual Report to shareholders, as well as how to cast a vote. Shareholders who receive the Notice and who would still like to receive a printed copy of the proxy materials can find instructions for requesting these materials included in the Notice. We plan to mail the Notice to shareholders by March 7, 2025.

Persons and groups who beneficially own in excess of 5% of our shares of common stock are required to file certain reports with the Securities and Exchange Commission, also referred to below as the "SEC", regarding such ownership pursuant to the Securities Exchange Act of 1934, as amended (the "Exchange Act"). The following table sets forth, as of February 18, 2025, the shares of our common stock beneficially owned by each person known to us who was the beneficial owner of more than 5% of the outstanding shares of our common stock. Percentage of shares of common stock outstanding are based on 127,514,858 shares of common stock outstanding as of February 18, 2025.

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REVOCATION OF PROXIES

Shareholders who execute proxies in the form solicited hereby retain the right to revoke them in the manner described below. Unless so revoked, the shares represented by such proxies will be voted at the Annual Meeting and all adjournments thereof. Proxies solicited on behalf of our Board of Directors will be voted in accordance with the directions given thereon. You may vote via the Internet, mobile or phone as described on your Proxy Card or voting instruction card. You may also vote by signing and returning your Proxy Card to the Company. Proxies we receive that are signed, but contain no instructions for voting, will be voted "FOR" the proposals set forth in this Proxy Statement for consideration at the Annual Meeting.

Proxies may be revoked by sending written notice of revocation to the Chief Counsel and Corporate Secretary of the Company, Richard K. Laws, at 3 Easton Oval, Suite 500, Columbus, Ohio 43219, or by returning a duly executed proxy bearing a later date by mail, or voting on a later date via the Internet, mobile or phone, as described on your Proxy Card or voting instruction card. The presence at the virtual Annual Meeting of any shareholder who had given a proxy shall not revoke such proxy unless the shareholder votes during the Annual Meeting or delivers a written revocation to the Chief Counsel and Corporate Secretary prior to the voting of such proxy.

PROPOSAL 1 - ELECTION OF DIRECTORS

Our Board of Directors is expected to consist of 11 members, effective immediately following the Annual Meeting. Our Bylaws provide that directors are divided into three classes, as nearly equal in number as reasonably possible, such that approximately one-thirdof the directors are to be elected annually. Our directors are generally elected to serve for a three-year period, or a shorter period if the director is elected to fill a vacancy, and until their respective successors shall have been elected and qualified. Four directors will be elected at the Annual Meeting and will serve until their successors have been elected and qualified. The Board of Directors, based on the recommendation of the Nominating and Corporate Governance Committee has nominated Robert M. Campana, Timothy B. Fannin, John P. Meegan and Mark A. Paup to serve as directors for three-year terms. Each individual is currently a member of the Board of Directors.

The table below sets forth certain information regarding our nominees and the composition of our Board of Directors as of December 31, 2024 (with age information as of December 31, 2024), including those Board members continuing in office following December 31, 2024 and the terms of office of Board members. It is intended that the proxies solicited on behalf of the Board of Directors (other than proxies in which the vote is withheld as to a nominee) will be voted at the Annual Meeting for the election of the nominees identified below. If one or more nominees is unable to serve, the shares represented by all such proxies will be voted for the election of such substitute or substitutes as the Board of Directors may nominate, based on the recommendation of the Nominating and Corporate Governance Committee. At this time, the Board of Directors knows of no reason why the nominees might be unable to serve, if elected. Except as indicated herein, there are no arrangements or understandings between the nominees and any other person pursuant to which such nominees were selected.

The Board of Directors unanimously recommends that you vote "FOR" each of the persons nominated by the Board of Directors.

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Directors and Nominees

The biographies of each of the nominees and continuing board members below contain information regarding the person's business experience and the experiences, qualifications, attributes or skills that caused the Nominating and Corporate Governance Committee and the Board of Directors to determine that the person should serve as a director. The principal occupation during the past five years of each of our directors is set forth below. All directors have held their present positions for five years unless otherwise stated. Each director is also a director of Northwest Bank.

Robert M. Campanais Chief Executive Officer of Campana Development, a real estate development company, and Chief Executive Officer of Campana Capital, a venture capital and private equity investment organization located in Westlake, Ohio. Mr. Campana previously served on the boards of directors of LNB Bancorp, Inc. and Lorain National Bank, and became a director of the Company and Northwest Bank upon the acquisition of LNB Bancorp, Inc. and Lorain National Bank in 2015. Mr. Campana is the former president of P.C. Campana Inc. and has been recognized in his community for his entrepreneurial skills. In addition, Mr. Campana's service on the boards of directors of LNB Bancorp, Inc. and Lorain National Bank for 17 years enables him to provide valuable insights to the Board particularly in evaluating the business conditions in Northwest Bank's Ohio markets, as well as in setting corporate strategy and compensation matters. He holds a business degree from Bowling Green State University and brings to the Board extensive experience in managing businesses and has significant experience in, and knowledge of, real estate development.

Deborah J. Chadsey is an attorney who has practiced law since 1989. She is a partner in the Buffalo, New York, law firm Kavinoky Cook, LLP. She has been on the Northwest Board of Directors since 2012. In addition, she sits on the Board of Directors of Kensington-Bailey Neighborhood Housing Services/Gloria Parks Community Center, a non-profitorganization. Ms. Chadsey graduated from Columbia University Law School in New York City, where she was a Harlan Fiske Stone Scholar and is licensed to practice law in Pennsylvania, New York, multiple federal district, bankruptcy and appellate courts and the United States Supreme Court. Ms. Chadsey brings to the Board specialization and experience in environmental and municipal law as well as commercial finance, land use and contract law.

Wilbur R. Davisco-foundedOntario Systems, LLC, a computer software company, serving as its Chief Executive Officer until 2008 and as its Chairman until the 2017 sale of the company. Capitalizing on his business experience, he launched Noble Why, LLC, an organizational effectiveness consulting firm dedicated to helping organizations foster passionate, purposeful and productive cultures where there is both an individual and collective pride in the work being accomplished. He has received recognition for his contributions to his industry and community, including an honorary doctorate in Business Management from Indiana Wesleyan University. Mr. Davis is the author of "Creating a Culture of Excellence, Changing the World of Work One Person at a Time", a sought-after speaker and a training consultant with over 30 years of leadership experience. Prior to co-foundingOntario Systems, he gained financial, engineering, and software systems experience with MutualBank and General Motors. He currently serves as a board member for a number of private organizations, including IU Health East Central Region and AAA Hoosier Motor Club. Mr. Davis is an entrepreneur with both his BS and MBA from Ball State University. Mr. Davis was a director of Mutual Bank and served as it Chair for the last 15 years prior to its acquisition by Northwest Bank. Prior to his board service with the Bank, Mr. Davis had served three years just after graduation from undergraduate School as the Bank's Accounting Supervisor. His responsibilities in that role also included overseeing the bank's technology infrastructure.

Timothy B. Fanninis a retired CPA and partner from the firm Catalano, Case, Catalano & Clark-Radzieta,LLP, Certified Public Accountants headquartered in Clearfield, Pennsylvania, where he worked for 28 years. He was formerly certified in both business valuations and financial forensics. From 2007 to 2009, he was an adjunct Professor of Accounting and Finance at Pennsylvania State University. Mr. Fannin served as board chairman for several economic development organizations in Pennsylvania's Clearfield and Elk Counties. Currently, he serves on the University of Pittsburgh at Bradford Advisor Board and on the board of directors of the Bradford Education Foundation. Mr. Fannin is a U.S. Army Veteran, earned a Business/Public Administration degree from the University of Pittsburgh and an MBA from Clarion University of Pennsylvania. His public accounting background and professional designations assist the Board in its oversight of the audit, tax, financial reporting and risk management areas.

Timothy M. Hunterhas been President and Chief Executive Officer of McInnes Rolled Rings in Erie, Pennsylvania, since 2003. He has served on the board of the Erie Regional Chamber and Growth Partnership. He is a past Chairman of the Manufacturer and Business Association and the Erie Community Foundation. Mr. Hunter is a CPA, having worked for Ernst & Young in Philadelphia, Pennsylvania, and earned an Accounting degree from Villanova University. Mr. Hunter has significant operations, finance and management experience in middle market manufacturing businesses combined with extensive knowledge and experience in accounting and reporting. He brings this background, coupled with his considerable business and community involvement, to the Board.

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John P. Meeganis an accomplished financial and operational executive with over 35 years of experience in the financial services industry and has been a member of Northwest's Board since 2010. He most recently served as Executive Vice President and Chief Operating Officer of Hefren-Tillotson Inc., a Pittsburgh-based broker/dealer, and Registered Investment Advisor for 16 years. He has held several executive positions with regional and national financial services companies. In these roles, he gained valuable oversight, financial and risk management skills. Mr. Meegan, a CPA, brings these skills to the Board and its committees. Specifically, Mr. Meegan's experience provides expertise to the Audit and Risk Management committees. Additionally, he has considerable not-for-profitand securities industry regulatory board service including Financial Industry Regulatory Authority (FINRA) throughout his career which enhances his financial and operational expertise. Mr. Meegan holds a BA degree from Amherst College and an MBA from New York University Graduate School of Business.

Mark A. Paupis the President and Chief Executive Officer for Zippo Manufacturing Company and W.R. Case and Sons Cutlery Company, both headquartered in Bradford, Pennsylvania. He is also the President and Director for NortheLights Enterprises located in Wellsville, New York. Since beginning his Zippo career in 1994, Mr. Paup has served as Vice President of Sales and Marketing, National Sales Manager, European Sales Manager and Global Marketing Director. He is a board member of the privately held companies ZIPCORP, Zippo Asia, Ltd., and Classic Zippo (Beijing) Commercial Co., Ltd, for which he serves as Chairman. He also serves as President and Director of Zippo International Inc., a privately held company. Mr. Paup is a board member for several non-profitorganizations including The Philo and Sarah Blaisdell Foundation, the University of Pittsburgh of Bradford Advisory Board and the Bradford Area Alliance, which he chairs, with the mission to improve economic development and community revitalization within McKean County, Pennsylvania. He attended Penn State Behrend and University of Pittsburgh-Bradford. Mr. Paup's extensive experience in the areas of sales, marketing, and strategic planning assist the Board in its oversight of Northwest's organic growth initiatives and strategic direction.

Louis J. Torchiowas appointed as President and Chief Executive Officer of both the Company and Northwest Bank and as a member of the Board of Directors of both entities in August 2022. He joined Northwest in 2018, serving as Senior Executive Vice President, Retail Lending. Prior to Northwest, Mr. Torchio served as Senior Vice President of Residential and Consumer Lending at Delaware County Bank. Active in his community and profession, Mr. Torchio has held various community board positions and senior management and executive committee positions at several large regional and community banking organizations. He is a demonstrated leader and manager with extensive experience building organizations through both organic practice and strategic acquisitions. He earned a degree in business administration with a minor in computer programming from Fairmont State University, as well as an MBA in finance and financial management services from Franklin University. Mr. Torchio's vast experience at both large and small institutions provides the breadth of knowledge needed to both lead the Company and serve on its Board of Directors.

David M. Tullio is the President and Chief Executive Officer of Custom Engineering Company and Lamjen, Inc., both located in Erie, Pennsylvania, and Venango Machine Company based in Wattsburg, Pennsylvania. For over 30 years, he has worked in various management positions within the manufacturing industry, assuming his current role at Custom Engineering in 1997. He currently serves on the boards of the Enterprise Development Center of Erie County as well as the Erie Community Foundation. Mr. Tullio earned a degree in Industrial Engineering from NorthwesteUniversity and an MBA from Behrend College of Pennsylvania State University. He brings extensive experience in manufacturing and technology companies to the Board, as well as broad community and board involvement.

Pablo A. Vegas is President and Chief Executive Officer of the Electric Reliability Council of Texas ("ERCOT"), headquartered in Austin, Texas, serving since 2022. From 2019 to 2022, he was Executive Vice President, Chief Operating Officer and President of Utilities for NiSource, Inc., located in Columbus, Ohio. Mr. Vegas has served in several roles, including Chief Customer Officer, Executive Vice President Gas Segment and President of the Columbia Gas Group with NiSource. Prior to NiSource, he held a variety of senior executive positions with American Electric Power (AEP), including President and Chief Operating Officer of AEP Ohio, AEP Texas and Chief Information Officer. Before his career in regulated utilities, he held senior leadership positions with IBM, PwC and Andersen Consulting. He has extensive experience in the electric and gas industries as well as in management consulting. Mr. Vegas serves on Global Advisory Board for the Harvard Business School and is a member of the Latino Corporate Directors Association and the Austin Area Research Organization. In 2022, he was appointed to the Texas Energy Reliability Council by Governor Abbott. Mr. Vegas attended the Advanced Management Program at Harvard Business School and earned his degree in Mechanical Engineering from the University of Michigan. He brings to the Board expertise in regulated gas and electric industries and extensive experience in profit and loss optimization, strategic planning, technology innovation and environmental sustainability initiatives.

Amber L. Williamsis Senior Vice President, Deputy General Counsel at Bath & Body Works, headquartered in Columbus, Ohio, a position she has held since 2018. With more than 20 years of experience in corporate law, she most recently served as VP Legal, Global Ethics & Compliance with Bath & Body Works and L Brands. Before joining L Brands, she held a variety of corporate counsel roles with Walmart, including Senior Associate General Counsel in two divisions, US Compliance and Real Estate Operations. She also served as Senior Counsel for NextiraOne, LLC. Active in organizations that serve the community, Ms. Williams

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sits on the board of the Equality Action Center and previously was on the board of the Greater Columbus Chapter of the American Red Cross. She earned her juris doctor degree from the University of Texas School of Law and her bachelor's degree in English from Oakwood University, Huntsville, Alabama. Ms. Williams brings to the Board extensive experience as a corporate lawyer and strategist in consumer-facing companies, as well as specialization in corporate ethics and compliance.

Executive Officers who are not Directors

The principal occupation during the past five years of each of our executive officers, other than Mr. Torchio, is set forth below.

Carey A. Barnumhas been employed by Northwest Bank since March 2020 and currently serves as Chief Auditor. In this role, she oversees the internal audit function for Northwest Bancshares, Inc. and Northwest. She previously served as Deputy Chief Auditor. From 2017 to 2020, Ms. Barnum was a Senior Audit Manager with M&T Bank. Before joining M&T Bank, she held various Audit roles including Audit Manager at KeyBank, Audit Director for First Niagara Bank and Audit Manager for Deloitte, all in Buffalo, New York. Ms. Barnum earned a degree in Business Administration from Niagara University, is a Certified Public Accountant (CPA) in the state of New York and earned the Certified Internal Auditor (CIA) designation from the Institute of Internal Auditors (IIA).

Gregory J. Betchkalhas been employed by Northwest Bank since March 2023 and currently serves as Chief Risk Officer. Prior to joining Northwest, he was Chief Risk Officer of Bread Financial Holdings, Inc., a position he held since 2017. He served as Chief Compliance Officer for several broker/dealers including ING's Advisor Network. He joined Citigroup and held several Compliance leadership positions in both the U.S. and Europe. Mr. Betchkal then joined KeyBank in Cleveland, serving at various times as the Chief Compliance Officer, Chief Operational Risk Officer and Chief Enterprise Risk Officer. He began his career as a securities regulator. Mr. Betchkal is a graduate of The Ohio State University College of Law.

Urich T. Bowershas been employed by Northwest Bank since June 2024 and currently serves as Chief Consumer Banking and Strategy Officer. With more than 25 years of experience, Mr. Bowers served as Senior Vice President, Head of Consumer Products, Strategy and Innovation at PNC Financial Services Group from 2022 to 2024, where he oversaw a portfolio of consumer households with more than $200 billion in deposits and led a team responsible for PNC's consumer checking, savings, time deposits, Virtual Wallet^® and digital experiences. Throughout his tenure at PNC, which began in 1999, Mr. Bowers held various leadership roles, including Head of Retail Savings, Liquidity and Fee Businesses; Chief Financial Officer - Retail Banking; Chief Financial Officer - Asset Management Group; SVP, Competitive Analysis and Planning, as well as positions in performance measurement, strategic planning, corporate marketing and affinity businesses. Mr. Bowers holds a bachelor's degree and MBA from the University of Pittsburgh.

James M. Colestrohas been employed by Northwest Bank since December 2007 and currently serves as Chief Retail Lending Officer overseeing the bank's retail lending, small business banking, international services and payments strategy and operations. Throughout his tenure with Northwest, Mr. Colestro has held several other leadership positions throughout the bank, including strategy and implementation of the bank's virtual lending program as well as development of the bank's mortgage sales force. Mr. Colestro is a graduate of the Pennsylvania Bankers Association School of Banking, and he holds a bachelor's degree in economics and business management with minors in finance and marketing from the University of Pittsburgh, as well as earning his MBA from The Ohio State University.

Thomas K. Creal IVhas been employed by Northwest Bank since April 2012 and currently serves as Chief Credit Officer. Prior to joining Northwest, he served as Director of Asset Management for De Lage Landen, FS and held various commercial lending positions at General Electric Capital in Manhattan and Siemens Financial Services. Mr. Creal graduated from Ohio University and the Graduate School of Banking at the University of Wisconsin-Madison.

Devin T. Cygnarhas been employed by Northwest Bank since March 2021 and currently serves as Chief Marketing and Communications Officer. From 2019 to 2021, he was Senior Vice President and Head of Marketing and Corporate Communications at ServiceLink, a division of Fidelity National Financial. He brings nearly 30 years of marketing experience spanning consumer, small business and mortgage banking. Mr. Cygnar has worked with organizations of various sizes, including PNC Bank as Head of Marketing for the Business Banking division, directing marketing strategy for all products and segments across the bank's geographic footprint. His career also includes experience with Fifth Third Bank. Active in his community, he serves on the boards of the Three Rivers Young Peoples Orchestra and Ohio DECA, and is a graduate of Leadership Pittsburgh. He holds degrees in Marketing and Finance from NortheIllinois University and is a graduate of the American Bankers Association Graduate School of Bank Marketing and Management at NorthwesteUniversity. Additionally, Mr. Cygnar is the executive sponsor for Northwest's PRISM employee resource group, supporting members and allies of the LGBTQ+ community.

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Jacques M. DesMarteauhas been employed by Northwest Bank since June 2023 and currently serves as Chief Commercial Banking Officer. With nearly 30 years of experience in commercial banking and finance, Mr. DesMarteau served as head of commercial banking at LendingClub Bank from August 2021 to June 2023. He spent 12 years in commercial banking leadership roles at TD Bank, including Head of Commercial Distribution, serving from 2009 to 2021. He also served as president of equipment finance at CIT Bank and spent 16 years in various positions with GE Commercial Finance and GE Commercial Solutions. Mr. DesMarteau earned a degree in Industrial Management from Purdue University and an MBA from Duke University.

Kyle P. Kanehas been employed by Northwest Bank since January 2021 and currently serves as Chief People Officer. From 2014 to 2020, Mr. Kane was Vice President, Global Human Resources, for Diebold Nixdorf in North Canton, Ohio. He also served as Senior Vice President of HR, Global Business Services, for Fidelity Investments in Boston, MA. Mr. Kane is a Trustee at the MarbuAcademy in New Albany, Ohio. He earned a degree in Marketing from Stonehill College in North Easton, Massachusetts, and is a graduate of the University of Wisconsin-Madison Graduate School of Banking.

Richard K. Laws has been employed by Northwest Bank since March 2013 and currently serves as Chief Counsel and Corporate Secretary of Northwest and Northwest Bancshares, Inc. Prior to joining Northwest, Mr. Laws served as Senior Counsel at ING Bank, fsb ("ING Direct") in Wilmington, Delaware. Mr. Laws holds a B.A. degree in Political Science from Juniata College where he graduated with Dean's Honors and a J.D., cum laude, from Widener University School of Law where he served as External Managing Editor of the Journal of Public Law and as a member of the National Moot Court Competition Team. Mr. Laws is also an Adjunct Professor at Penn State Law where he has taught courses in Professional Responsibility and has designed and currently teaches an experiential learning course entitled "ModeIn-HouseCounsel."

Douglas M. Schosserhas been employed by Northwest Bank since March 2024 and currently serves as Chief Financial Officer. Prior to joining Northwest, he served as Chief Accounting Officer for KeyCorp from 2014 until 2024, where he was responsible for SEC and Regulatory reporting, Accounting Policy, Financial Systems, Procurement and compliance with the Sarbanes-Oxley Act. Prior to this he served as Chief Financial Officer for the Commercial Bank from 2010 until 2014. Additionally, he served on several committees, including: the Trust Oversight Committee; Operational Risk Committee; Consumer Credit Committee; Asset and Liability Committee, Third Party Risk Management; Anti Money Laundering Oversight Committee; and Model Risk Committee in addition to serving as a director of KeyBanc Capital Markets, Inc. Mr. Schosser is a graduate of Miami University in Oxford, Ohio.

Scott J. Watsonhas been employed by Northwest Bank since February 2019 and currently serves as Chief Information Officer. Mr. Watson has an extensive 30-yearcareer in bank information technology and operations. From 2016 to 2019, he served as Senior Vice President, Chief Information Officer, for Cape Cod Five, Orleans, Massachusetts. From 2010 to 2016, Mr. Watson served as an Executive Director of Bank Operations and Technical Director of Bank Systems with USAA. From 2007 to 2010, he served in technology leadership roles for Wells Fargo and Wachovia. Mr. Watson earned a degree in Business Administration from Kent State University and is a graduate of the CBA Executive Banking School.

Board Diversity

Given the carefully considered size of the Board and the substantial, meaningful relationships that Northwest maintains with its directors, we firmly believe that the Board is appropriately diverse to the fullest extent feasible. This diversity equips the Board to serve the best interests of the Company effectively and robustly.

The following table provides the diversity statistics of the Company's Board of Directors as of December 31, 2024 and 2023, respectively. The information provided below was based on voluntary information self-identified by each member of the Board of Directors.

Board Independence

The Board of Directors has determined that Directors Campana, Chadsey, Davis, Fannin, Hunter, Meegan, Paup, Tullio, Vegas and Williams are, "independent" within the meaning of the Nasdaq corporate governance listing standards. Mr. Torchio is not independent by virtue of being an employee of the Company.

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In determining the independence of the directors and the nominees listed above, the Board of Directors reviewed the transactions reported under "Transactions With Certain Related Persons," below, as well as the following transactions and relationships, none of which are required to be reported under "Transactions With Certain Related Persons". Each of the following products or services are provided by Northwest Bank. Director Campana has mortgages, a home equity line of credit, commercial loan and credit card. Kavinoky Cook, LLP, where Director Chadsey is a law partner, has a commercial line of credit. Various companies, where Director Davis is a partner, have commercial loans and commercial lines of credit. Director Fannin has an unsecured line of credit. Mr. Meegan has credit cards. Mr. Paup has a home equity line of credit. The spouse of Director Mark Paup, Toni Paup, has a consumer line of credit, mortgage, home equity line of credit and credit cards. Director Tullio has a residential mortgage and home equity line of credit. Lamjen Inc., subsidiary of Custom Engineering Company, where Director Tullio is President and CEO, has a commercial loan and a commercial line of credit. Additional loans (including residential mortgage loans, lines of credit and credit cards) have been made to related persons of Directors Campana, Chadsey, Davis, Paup and Tullio.

Board Leadership Structure and Oversight

We currently have a separate independent Chairman and Chief Executive Officer ("CEO") structure. The Board of Directors believes that such structure is in the best interest of the Company at this time, as it allows for a more effective monitoring and objective evaluation of the performance of management. The role of the Independent Chairman of the Board includes facilitating oversight of management, engaging with shareholders and leading our Board of Directors on all matters. Our CEO has primary responsibility for the operational leadership and strategic direction of the Company. Mr. Fannin currently serves as our Independent Board Chairman and Mr. Torchio currently serves as our CEO.

A key responsibility of the Board of Directors is to help ensure that an effective process is in place to provide continuity of leadership over the long term at all levels in our company. Each year, succession planning reviews are held at every significant organizational level of our company, culminating in a full review of senior leadership talent by the independent directors. During this review, the CEO and the independent directors discuss future candidates for senior leadership positions, succession timing for those positions, and development plans for the highest-quality candidates. This process ensures continuity of leadership over the long term, and it forms the basis on which we make ongoing leadership assignments. It is a key success factor in managing the long-term planning and investment lead times of our business.

In addition, the CEO maintains in place at all times, and reviews with the independent directors, a confidential plan for the timely and efficient transfer of responsibilities in the event of an emergency or sudden incapacitation or departure.

The Board of Directors is actively involved in oversight of risks that could affect the Company. This oversight is conducted primarily through the Risk Management Committee of the Board of Directors, consisting of five independent directors, who meet at least quarterly for the specific purpose of evaluating our exposure to all risks specifically identified in banking regulations: credit, interest rate, strategic/capital, market price, liquidity, operational, business resumption, compliance/legal/regulatory, foreign exchange and reputation. The Risk Management Committee reports are prepared and presented by our Chief Risk Officer and reports of Committee meetings are made to the full Board of Directors during the next scheduled Board meeting. The Board of Directors also satisfies this responsibility through reports to the Board of Directors by the committee chair of all board committees regarding the committees' considerations and actions, through review of minutes of committee meetings and through regular reports directly from officers responsible for oversight of particular risks within the Company. All board committees are responsible for the establishment of policies that guide management and staff in the day-to-dayoperation of the Company and Northwest Bank such as lending, risk management, asset/liability management, investment management and others.

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Stock Ownership

The following table reflects common stock of the Company beneficially owned by directors, each executive officer named in the "Summary Compensation Table", all of our directors and executive officers as of February 18, 2025 as a group, except as otherwise indicated below.

None of our Directors or Executive Officers had any shares pledged as collateral as of February 18, 2025. We have adopted a policy that prohibits our insiders from (i) pledging of our stock as collateral against a loan or line of credit or holding Company stock in a margin account; and (ii) conducting any hedging activities (including prepaid variable forward contracts, equity swaps, collars, and exchange funds) designed to offset any decrease in the market value of our common stock.

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Meetings and Committees of the Board of Directors

Our business is conducted at regular and special meetings of the full Board and its standing committees. In addition, our independent directors meet in executive sessions. The standing committees consist of the Audit, Compensation, Innovation and Technology, Nominating and Corporate Governance, Risk Management and Trust Committees. During the year ended December 31, 2024, the Board of Directors of the Company met at 6 regular meetings and held 2 special meetings that were conducted either in-personor by way of video conferencing. No member of the Board or any committee thereof attended fewer than 75% of the aggregate of: (i) the total number of meetings of the Board of Directors (held during the period for which they have been a director); and (ii) the total number of meetings held by all committees of the Board on which they served (during the periods that they served).

The following table sets forth the members of our Audit, Compensation and Nominating and Corporate Governance Committees as of December 31, 2024.

* Denotes Chairperson.

The duties and responsibilities of the Audit, Compensation and Nominating and Corporate Governance Committees are as follows.

Audit Committee.Each member of the Audit Committee is "independent" as defined in the Nasdaq corporate governance listing standards and under Securities and Exchange Commission Rule 10A-3.The Board of Directors has determined that each of Messrs. Fannin, Hunter and Meegan qualifies as an "audit committee financial expert" as that term is used in the rules and regulations of the Securities and Exchange Commission. Information with respect to the experience of Messrs. Fannin, Hunter and Meegan is included in "Directors". Our Board of Directors has approved a written charter for the Audit Committee, which is available on our website at www.northwest.com.

The duties and responsibilities of the Audit Committee include, among other things:

Compensation Committee.Each member of the Compensation Committee is "independent" as defined in the Nasdaq corporate governance listing standards and under Securities and Exchange Commission Rule 10C-1.The Compensation Committee meets at least quarterly, or more frequently if necessary. Our Board of Directors has approved a written charter for the Compensation Committee, which is available on our website at www.northwest.com.

The purpose of the Compensation Committee is to, among other things, evaluate:

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In furtherance of these objectives, the Compensation Committee is responsible, among others, for:

The Compensation Committee has available the resources and authority necessary to properly discharge its duties and responsibilities, including the authority to retain counsel and other experts or consultants. The Compensation Committee, in performing these duties and responsibilities with respect to director and executive officer compensation, relies on the assistance of professionals within our Human Resources Department. During 2024, the Compensation Committee utilized Pearl Meyer & Partners, LLC ("Pearl Meyer"), an independent executive compensation consulting firm, for an independent review of director and executive officer compensation, including benefits and equity awards. For the year ended December 31, 2024, we incurred $93,000 of fees for their compensation consulting services.

Nominating and Corporate Governance Committee. Each member of the Nominating and Corporate Governance Committee is considered "independent" as defined in the Nasdaq corporate governance listing standards. Our Board of Directors has approved a written charter for the Nominating and Corporate Governance Committee, which is available on our website at www.northwest.com.

The functions of the Nominating and Corporate Governance Committee include the following:

The Committee identifies nominees by first evaluating the current members of the Board of Directors willing to continue in service. Current members of the Board with skills and experience that are relevant to our business and who are willing to continue in service are first considered for re-nomination,balancing the value of continuity of service by existing members of the Board with that

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of obtaining a new perspective. In addition, the Committee is authorized by its charter to engage a third party to assist in the identification of director nominees, if it chooses to do so. The Nominating and Corporate Governance Committee would seek to identify a candidate who, at a minimum, satisfies the following criteria:

The Board seeks independent directors who represent a mix of backgrounds and experiences that will enhance the quality of the Board's deliberations and decisions. The Board is particularly interested in maintaining a mix that includes active or retired business professionals and senior executives, particularly those with experience in management, operations, finance, accounting, banking, risk management, compliance, information technology, or marketing and sales. As part of its periodic self-assessment process, the Board discusses the diversity of specific skills and characteristics necessary for the optimal functioning of the Board in its oversight of the Company over both the short and long term. The Nominating and Corporate Governance Committee then gives consideration to these specific skill areas or experiences when considering candidates for nomination. Specific qualities or experiences could include matters such as experience in our industry, financial or technological expertise, leadership experience and relevant geographical experience. The effectiveness of the Board's diverse mix of skills and experiences is considered as part of each Board self-assessment.

In addition to meeting these qualifications, a person is not qualified to serve as a director if they: (1) are under indictment for, or has ever been convicted of, a criminal offense involving dishonesty or breach of trust and the penalty for such offense could be imprisonment for more than one year; (2) are a person against whom a banking agency has, within the past ten years, issued a cease and desist order for conduct involving dishonesty or breach of trust and that order is final and not subject to appeal; or (3) have been found either by a regulatory agency whose decision is final and not subject to appeal or by a court to have (i) breached a fiduciary duty involving personal profit or (ii) committed a willful violation of any law, rule or regulation governing banking, securities, commodities or insurance, or any final cease and desist order issued by a banking, securities, commodities or insurance regulatory agency.

The Committee will also take into account whether a candidate satisfies the criteria for "independence" under the Nasdaq corporate governance listing standards. We have also recently adopted stock ownership guidelines, which are described in "Compensation Discussion and Analysis-Other Practices, Policies & Guidelines-Stock Ownership Guidelines".

The Board of Directors holds itself and all members of various committees to the highest standard of professional and personal conduct. These requirements are included in our Code of Ethics and the Nominating and Corporate Governance Committee Charter and other committee charters. In addition, directors are required to have ongoing education, and the Board of Directors regularly reviews director compensation to confirm the reasonableness of such compensation.

Procedures for the Recommendation of Director Nominees by Shareholders. The Nominating and Corporate Governance Committee has adopted procedures for the submission of recommendations for director nominees by shareholders. There have been no material changes to these procedures since they were previously disclosed in our Proxy Statement for the 2024 Annual Meeting of Shareholders. If a determination is made that an additional candidate is needed for the Board of Directors, the Nominating and Corporate Governance Committee will consider candidates recommended by our shareholders. Shareholders can submit the names of qualified candidates for Director by writing to us at 3 Easton Oval, Suite 500, Columbus, Ohio 43219, Attention: Chief Counsel and Corporate Secretary. The Chief Counsel and Corporate Secretary must receive a submission not less than 180 days prior to the one-yearanniversary date of our proxy statement relating to the preceding year's annual meeting of shareholders, which, for the 2026 Annual Meeting of Shareholders, is no later than September 8, 2025.

The submission must include the following information:

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A director nomination submitted by a shareholder for presentation by the shareholder at an Annual Meeting of Shareholders must comply with the procedural and informational requirements described in our Bylaws. Please see "Advance Notice of Business or Director Nominations To Be Presented at an Annual Meeting" below for more information on nominating directors.

Shareholder Communications with the Board. A shareholder of the Company who wants to communicate with the Board of Directors or with any individual director can write to: Board of Directors, Northwest Bancshares, Inc., 3 Easton Oval, Suite 500, Columbus, Ohio 43219, Attention: Chief Counsel and Corporate Secretary. The letter should indicate that the author is a shareholder of the Company and, if shares are not held of record, should include appropriate evidence of stock ownership. Depending on the subject matter, the Chief Counsel and Corporate Secretary will:

The Chief Counsel and Corporate Secretary will prepare a general summary of those communications that were not forwarded and provide a summary of activity to the Board of Directors each quarter.

Attendance at Annual Meetings of Shareholders

Although we do not have a formal written policy regarding director attendance at Annual Meetings of Shareholders, it is expected that directors will attend these meetings in person or virtually, absent unavoidable scheduling conflicts. All of our then-current directors attended our prior year's Annual Meeting of Shareholders.

Policy Regarding Majority Voting

The Board of Directors has adopted a majority voting policy ("Policy"), which is utilized for the election of any director at any meeting of shareholders for uncontested elections and is not applicable for contested elections. For the purpose of the Policy, an "uncontested election" shall mean an election of directors where the only director nominees are those individuals recommended by the Board of Directors of the Company.

Pursuant to the Policy, any incumbent director nominee in an uncontested election who receives a greater number of votes "WITHHELD" than votes cast "FOR" at the shareholders meeting shall promptly tender his or her proposed resignation following certification of the shareholder vote.

The Nominating and Corporate Governance Committee will promptly consider the resignation and will recommend to the Board of Directors whether to accept the resignation or to take other action, including rejecting the resignation and addressing any apparent underlying causes of the failure of the director to obtain a majority of votes "FOR" such nominee. When considering the resignation and making its recommendation, the Nominating and Corporate Governance Committee will consider all factors deemed relevant by its members including, without limitation, the underlying reasons for the shareholders' "WITHHELD" votes for the

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director (to the extent ascertainable), the length of service and qualifications of the director, the director's contributions to the Company, whether the acceptance or rejection of the resignation will have any adverse effect on the Company's compliance with any applicable law, rule, regulation or governing document, to determine whether the acceptance of the resignation is in the best interests of the Company and its shareholders.

The Board of Directors will act on the Nominating and Corporate Governance Committee's recommendation no later than at its first regularly scheduled meeting following certification of the shareholder vote, but in any case, no later than 90 days following the certification of the shareholder vote.

If a majority of the members of the Nominating and Corporate Governance Committee are required to tender a resignation at the same election, then the other independent directors will appoint a special board committee amongst themselves solely for the purpose of considering the resignations and will recommend to the Board whether to accept, reject or take other action as to the resignations.

Code of Ethics

We have adopted a Code of Ethics that is applicable to our directors, officers and employees, including a Code of Ethics for Senior Financial Officers attached thereto. The Code of Ethics is available on our website at www.northwest.com. Amendments to and waivers from the Code of Ethics with respect to directors and executive officers will also be disclosed on our website.

Audit Committee Report

The Audit Committee has issued a report that states as follows:

Based on the review and discussions referred to above, the Audit Committee recommended to the Board of Directors that the audited consolidated financial statements be included in our Annual Report on Form 10-Kfor the year ended December 31, 2024 for filing with the Securities and Exchange Commission.

This report has been provided by the Audit Committee, which consists of Directors Meegan, who serves as Chairperson, Chadsey, Fannin, Hunter and Williams.

Compensation Committee Interlocks and Insider Participation

Our Compensation Committee determines the salaries to be paid each year to the CEO and those executive officers who report directly to the CEO. The Compensation Committee currently consists of Directors Hunter, who serves as Chairperson, Campana, Davis, Tullio and Vegas. None of these individuals was an officer or employee of the Company during the year ended December 31, 2024, or is a former officer of the Company. Except as described below for Director Campana, none of the members of the Compensation Committee had any relationship requiring disclosure under "Transactions with Certain Related Persons".

During the year ended December 31, 2024, (i) no executive officer of the Company served as a member of the Compensation Committee (or other board committee performing equivalent functions or, in the absence of any such committee, the entire board of directors) of another entity, one of whose executive officers served on the Compensation Committee of the Company; (ii) no executive officer of the Company served as a director of another entity, one of whose executive officers served on the Compensation Committee; and (iii) no executive officer of the Company served as a member of the compensation committee (or other board

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committee performing equivalent functions or, in the absence of any such committee, the entire board of directors) of another entity, one of whose executive officers served as a director of the Company.

Compensation Discussion and Analysis

This Compensation Discussion & Analysis ("CD&A") explains our executive compensation program for our named executive officers ("NEOs") listed below. This CD&A also describes the Compensation Committee's process for making pay decisions, as well as its rationale for specific decisions related to compensation paid in the fiscal year ended December 31, 2024.

On June 18, 2024, the Company announced the departure of John J. Golding, former Chief Consumer Banking Officer, effective June 17, 2024.

Executive Summary. The Company is a bank holding company headquartered in Columbus, Ohio. The Company operates Northwest Bank (also referred to herein as the "Bank"), a full-service financial institution headquartered in Warren, Pennsylvania. Through this subsidiary, the Company, as of December 31, 2024, operates 130 full-service financial centers, eleven free standing drive-upfacilities, and 169 automated teller machines in Pennsylvania, New York, Ohio and Indiana. The Company has operated as a community-oriented financial institution since 1896 and has demonstrated a patteof sustained expansion resulting from strong internal growth combined with a series of mergers, acquisitions, and new office openings.

2024 Business Highlights. Throughout 2024, despite industry-wide challenges, we continued to make strategic decisions to better position Northwest for growth and continued success. This included a securities portfolio repositioning successfully completed in 2Q, a continued focus on growing our Commercial lending portfolio, and investments in colleagues and technology to create the infrastructure needed to support future growth. Commercial loans grew to $2 billion at December 31, 2024, an increase of $350 million from prior year end.

Amidst industry funding and liquidity challenges, we successfully navigated the landscape, culminating in a 1.4% increase in total deposits, reaching $12.14 billion by the end of 2024. This achievement not only underscores our ability to maintain a stable and diversified deposit base but also reflects our capacity to adapt and grow during challenging market conditions. We continue to lead our peers with one of the lowest cost of funds while maintaining one of the lowest uninsured deposit bases in the nation at less than 25% of total deposits (12% when excluding intercompany and collateralized deposits) with an overall average deposit balance of $18,000 per account.

Reported net income for the year declined by $34.6 million to $100.3 million, or $0.79 per diluted share, adjusted net income (excluding securities repositioning loss and merger/restructuring expenses) decline by $7 million to $132.8 million, or $1.04 per diluted share. Furthermore, we delivered above budgeted returns on average shareholders' equity and assets, with annualized adjusted returns for 2024 at 8.49% and 0.92%, respectively, showcasing our commitment to delivering value to our shareholders. Additionally, our net interest income was flat vs prior year, which reflects our ability to effectively manage the interest rate environment and optimize our balance sheet.

Despite the macroeconomic challenges, our asset quality remains stable with overall delinquency at approximately 0.9% and 90-daydelinquency at just 0.2%. In addition, our capital levels remain strong with Tangible Common Equity to Tangible Assets Ratio increasing to 8.65% and all regulatory capital ratios comfortably above "Well Capitalized" levels providing flexibility for future growth and capital management strategies.

2024 Compensation Highlights.Our executive compensation program has three primary elements: base salary, annual incentives, and long-term equity incentives. Each of these compensation elements serves a specific purpose in our compensation strategy. Base salary is an essential component to any market-competitive compensation program. Annual incentives reward the achievement of short-term goals, while long-term incentives drive our NEOs to focus on long-term sustainable shareholder value

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creation. Based on our performance and consistent with the design of our program, the Compensation Committee made the following executive compensation decisions for fiscal 2024:

Best Compensation Practices& Policies. We also believe the following practices and policies within our program promote sound compensation governance and are in the best interests of our shareholders and executives:

Shareholder Say-on-PayVote. In accordance with SEC rules at our 2024 Annual Meeting of Shareholders, we held an advisory, non-bindingvote to approve the compensation of our NEOs as described in the proxy statement (commonly referred to as a "Say-on-PayVote"), which vote received over 96% of the votes cast in favor of the proposal; and an advisory, non-bindingvote on the frequency of the Say-on-PayVote in the future (the "Frequency Vote"). At our 2024 Annual Meeting of Shareholders, our shareholders also recommended that we hold a Say-on-PayVote on an annual basis. Our Compensation Committee considered the recommendation of the shareholders at our previous Annual Meeting of Shareholders in reviewing executive compensation and in determining the frequency of future Say-on-PayVotes and has determined to include the Say-on-PayVote in our proxy materials for each Annual Meeting of Shareholders until the next Frequency Vote, which will occur no later than the 2029 Annual Meeting of Shareholders.

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What Guides Our Program

Executive Compensation Philosophy and Objectives. Our executive compensation philosophy is driven by the following guiding principles that underpin the critical connections between performance, long-term value creation, talent management, compensation governance and our cultural values:

Elements of Pay: Total Direct Compensation. Our executive compensation philosophy is supported by the following principal elements of pay:

Pay Mix.The executive compensation program uses a mix of fixed and variable pay. The program is structured to create a meaningful balance between achieving strong short-term annual results while ensuring long-term viability and success. Therefore, the mix of incentives is reviewed and determined regularly by the Compensation Committee based on the short- and long-term objectives of the business. The charts below show the target annual total direct compensation of our CEO and our other NEOs for fiscal 2024. These charts show that a significant portion of executive compensation is variable (61% for our CEO and an average of 51% for our other NEOs). These charts do not include any one-timeequity grants or awards outside of target annual total direct compensation, if any.

Executive Compensation Decision-Making Process

The Role of the Compensation Committee. The Compensation Committee oversees the executive compensation program for our NEOs. The Compensation Committee is comprised of independent, non-employeemembers of the Board. The Compensation

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Committee works closely with its independent compensation consultant and management to examine the effectiveness of the Company's executive compensation program including cash compensation, annual incentive compensation, equity-based awards, and other benefits and perquisites throughout the year. Details of the Compensation Committee's authority and responsibilities are specified in its charter, which may be accessed on our website at www.northwest.com. The Compensation Committee makes all final compensation and equity award decisions regarding our NEOs, except for the CEO, whose compensation is determined by the independent members of the full Board, based upon recommendations of the Compensation Committee.

Members of our management team attend regular Compensation Committee meetings where executive compensation, Company and individual performance, and competitive compensation levels and practices are discussed and evaluated. Only the Compensation Committee members can vote on decisions regarding NEO compensation.

The CEO reviews his recommendations pertaining to the compensation of the other NEOs with the Compensation Committee providing management input, transparency, and oversight. Approvals of NEO compensation other than CEO compensation are made by the Compensation Committee. The CEO does not participate in the deliberations of the Compensation Committee regarding his own compensation. Independent members of the Board make all final determinations regarding CEO compensation.

The Role of the Independent Consultant. During 2024, the Compensation Committee retained Pearl Meyer, an independent executive compensation consulting firm, to provide comprehensive consulting services to the Compensation Committee, including to:

Pearl Meyer reports directly to the Compensation Committee and does not provide any other services to the Company. The Compensation Committee analyzed whether the work of Pearl Meyer raised any conflicts of interest, taking into consideration the following factors, among others: (i) the provision of other services to the Company by Pearl Meyer; (ii) the amount of fees the Company paid to Pearl Meyer as a percentage of Pearl Meyer's total revenues; (iii) Pearl Meyer's policies and procedures that are designed to prevent conflicts of interest; (iv) any business or personal relationship of Pearl Meyer or the individual compensation advisors employed by Pearl Meyer with any executive officer of the Company; (v) any business or personal relationship of the individual compensation advisors with any member of the Compensation Committee; and (vi) any stock of the Company owned by Pearl Meyer or the individual compensation advisors employed by Pearl Meyer. The Compensation Committee determined, based on its analysis of the above factors, among others, that the work of Pearl Meyer and the individual compensation advisors employed by Pearl Meyer as compensation consultants to the Company have not created any conflicts of interest.

The Role of Peer Group Companies.The Compensation Committee strives to set a competitive level of total compensation for each NEO as compared with executive officers in similar positions at peer companies. In evaluating NEO compensation, we utilize market information which is supported by benchmark data from our peer group, as well as Pearl Meyer and McLagan, an Aon Hewitt company ("McLagan"), both nationally recognized compensation consulting firms. We establish compensation targets for substantially all of our employees so that their total cash compensation opportunity would be approximately between 15% below to 15% above the market median for fully qualified and experienced employees. For the year ended December 31, 2024, we utilized financial services survey data from McLagan in reviewing compensation for substantially all employees, including executive officers.

McLagan was utilized by the Company based on their comprehensive set of reports within the financial services industry. McLagan provides complete compensation coverage for each job position in the financial services industry by extensive analysis of salaries, incentive eligible positions, incentive amounts with regard to base salaries, and total cash compensation. In addition, analysis by company size and geographic location is performed and categorized by jobs based on levels of responsibility and experience.

On an annual basis, with assistance from Pearl Meyer, the Company conducts a benchmarking and peer group exercise with the Compensation Committee. In the fall of 2023, Pearl Meyer presented a review of the Company's peer group using publicly traded U.S. banks with assets as of September 30, 2023, ranging from approximately 50% to 200% of the Company's asset size. The Compensation Committee considered the "compatibility" and "comparability" of each company when selecting the 2024 peer group. The Compensation Committee reviewed, among other things, each peer company's asset size, earnings, portfolio mix, geographical location, organizational structure and governance, number of employees, number of financial centers and service offerings.

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Following selection and approval by the Compensation Committee of the peer group listed in the table, the Company was positioned near the median of the group in terms of asset size.

2024 Executive Compensation Program in Detail

Base Salary. Base salary represents annual fixed compensation and is a standard element of compensation necessary to attract and retain executive leadership talent. In making base salary decisions, the Compensation Committee considers the CEO's recommendations, as well as each NEO's position and level of responsibility within the Company. The Compensation Committee considers factors such as competitive market data as well as individual performance, experience, tenure, internal equity, and employee potential. Base salaries are adjusted using a merit increase pool and a performance evaluation process that consists of general rating factors. Merit increases are based on the NEO's overall performance rating, the time interval and any added responsibilities since the last salary increase. For 2024, the Compensation Committee approved salary increases for the NEOs as follows:

Mr. Golding received a 6% increase in 2024 at the same time as the others listed in the table above.

Annual Incentives. We provide performance-based cash incentive awards to eligible personnel, including executive officers, under the Management Bonus Plan. Cash incentives are used to motivate and reward achievement of corporate and individual performance objectives which are strategically aligned with enhancing shareholder value. Funding for the Management Bonus Plan is based on an assessment of the Company's actual performance relative to the Compensation Committee's pre-establishedfinancial performance levels based on a combination of financial factors as well as a comparison against a predetermined peer group. Actual payouts depend on the achievement of pre-determinedfinancial performance objectives and can range from 0% to 150% of target award amounts.

Management Bonus Plan Target Opportunity.Target annual bonus opportunities are expressed as a percentage of base salary and were established by the NEOs' level of responsibility and their ability to impact overall results. The Compensation Committee also considers market data in setting target award amounts. Target award opportunities for 2024 were as follows:

Financial Performance Objectives, Levels& Results.For the year ended December 31, 2024, the Management Bonus Plan required that two threshold metrics be satisfied in order for any cash incentive payout to be considered. These threshold metrics included achievement of net charge-offs of 0.50% or less and total loan delinquency of 3.00% or less. Once these threshold metrics were met, the financial factors considered to determine the payout level for the year ended December 31, 2024 were: adjusted retuon average assets ("adjusted ROAA"), adjusted retuon average equity ("adjusted ROAE"), efficiency ratio, and loan growth. Individual performance ratings also are considered when determining the actual payout amount. After the conclusion of the fiscal year, the CEO may suggest that the Compensation Committee consider discretionary adjustments to cash incentive awards that are consistent with the long-term advancement of our strategic initiatives.

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The Management Bonus Plan sets levels of corporate performance targets, resulting in cash incentive payments to the NEOs in amounts ranging from 0% to 150% of target depending on actual performance.

The Compensation Committee has discretion under the Management Bonus Plan to adjust the overall performance level achieved to include or exclude the effect of extraordinary, unusual or non-recurringitems, changes in tax or accounting rules or the effect of mergers or acquisitions. These adjustments aim to maintain fairness to both participants and shareholders, while also fostering actions that promote the long-term health of the business and align with predetermined performance goals.

In 2024, the economic challenges facing regional financial institutions persisted, including elevated interest rates, increased credit costs, industry-wide funding constraints, and compressed net interest margins. At the start of the year, the Company set its financial targets based on reasonable expectations of the market conditions at that time. However, as the year progressed, it became clear that maintaining disciplined loan growth, particularly in the consumer portfolio, was critical to balancing profitability and risk. As a result, the Company focused on commercial loan expansion, achieving a 21% year-over-year increase, while deliberately limiting consumer loan growth to preserve pricing discipline and long-term financial stability.

While this approach ultimately strengthened key financial metrics, it also resulted in a shortfall on the Loan Growth KPI. As a result, initial funding under the Management Bonus Plan was determined to be 92.47% of target based on the following actual performance outcomes:

While commercial loan growth increased significantly (21%) year-over-year, the leadership team strategically limited loan growth within the consumer portfolio, focusing on pricing discipline and profitability versus a focus on asset growth. Recognizing that this shift in loan mix was a deliberate response to economic conditions, not a failure to drive overall loan growth, the Compensation Committee determined that the original loan growth target did not fully reflect the Company's actual performance achievements. Additionally, the Company exceeded its original adjusted net income budget by $4 million performance at approximately $4.4MM (3%). Based on these considerations, the Compensation Committee elected to fund the Management Bonus Plan at 100%

Management Bonus Payouts.Based on the above results, the Compensation Committee determined that management bonuses should be paid at target for Company performance with additional multipliers based on each NEOs performance, as summarized in the table below:

As a result of Mr. Golding's termination of employment on June 17, 2024, Mr. Golding was not eligible to receive a bonus for fiscal year 2024.

Long-Term Stock-Based Compensation. The purpose of our 2022 Equity Incentive Plan is to promote the long-term financial success of the Company and its subsidiaries, including Northwest Bank, by providing a means to attract, retain and reward individuals who contribute to that success and to further align their interests with those of the Company's shareholders through the ownership of shares of Company stock. In 2024, the Compensation Committee granted long-term incentive compensation that is

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balanced between retention and forward-looking performance incentives. To place a heavier emphasis on performance, the Compensation Committee granted Mr. Torchio's award using a mix of 50% PSUs and 40% RSUs. Awards granted to the other NEOs used a combination of RSUs and PSUs as follows:

The Compensation Committee believes that this combination, coupled with meaningful stock ownership requirements, will ensure that executives are focused on creating shareholder value and the long-term success of the Company.

Target long-term opportunities are expressed as a percentage of base salary at the time of grant and were established according to each NEO's level of responsibility and his or her ability to impact overall results. The Compensation Committee also considers market data in setting target award amounts. Target award opportunities for 2024 were as follows:

Mr. Golding, our former Chief Consumer Banking Officer, also received a grant of RSUs and PSUs consistent with our standard equity grant practices. The target value of Mr. Golding's long-term incentive awards was $177,289, or 45%, of his then current base salary. All of Mr. Golding's outstanding awards of RSUs and PSUs were forfeited as of June 17, 2024 upon his termination of employment.

Fiscal 2024 Annual Long-Term Incentive Grants.For fiscal 2024, the NEOs received the following awards (excluding any one-timegrants or awards):

The number of units was calculated using the per-shareclosing price of the Company's common stock on the grant date approved by the Board. Executives may eathe performance share unit portion of their awards by achieving certain metrics as established by the Compensation Committee over a three-year performance period.

All awards granted under our 2018 Equity Incentive Plan and 2022 Equity Incentive Plan are subject to clawback if the Company is required to prepare an accounting restatement due to material noncompliance of the Company as a result of misconduct, with any financial reporting requirement under federal securities laws. In addition, awards are subject to clawback under the Company's Clawback Policy designed to comply with SEC and Nasdaq rules regarding the recoupment of erroneously awarded compensation. See "Other Practices, Policies and Guidelines-Clawback Policy".

A Closer Look at PSUs.The Compensation Committee believes that PSUs provide appropriate incentives for management to focus on long-term financial results, and that these performance goals correlate with the value of our common stock. NEOs can eabetween 0% and 150% of their target award opportunity. The actual number of PSUs that are earned and vested is based on the

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achievement of pre-determinedfinancial performance metrics against the KRX index at the end of a three-year performance period, as outlined in the following table:

The number of PSUs earned at the end of the three-year performance period will be based on the attainment of performance levels, including threshold, target, and maximum, and associated payouts will be established at the beginning of the performance cycle as follows:

Performance below "threshold" for a given performance measure will result in forfeiture of the respective PSUs. Threshold performance will be achieved at the 25th percentile of the approved compensation peer group, target performance at the 50th percentile of the peer group, and maximum performance is at the 75th percentile of the peer group. At the end of each performance cycle, actual performance and the resulting payouts will be determined. Performance between threshold, target, and maximum will be determined using straight line interpolation and rounded up to the nearest whole number of PSUs.

Other Practices, Policies & Guidelines

Stock Ownership Guidelines. Our Board has adopted stock ownership guidelines for our NEOs and our non-employeedirectors, which must be achieved during a five-year phase-inperiod after the NEO or director first becomes subject to the guidelines. The Board believes these guidelines further align our NEOs' and our non-employeedirectors' interests with the interests of our shareholders. The minimum equity ownership guidelines for our continuing NEOs and our non-employeedirectors are as follows:

If the ownership requirement has not been met by the fifth anniversary of the date the NEO became subject to the ownership requirement multiple, then 100% of net shares acquired annually from employee equity awards must be retained until requirements are met. Shares that count towards the ownership requirement include shares owned and vested and unvested RSUs. Non-QualifiedStock Options, whether vested or unvested, and unvested PSUs do not count towards the ownership requirement. All NEOs currently meet the stock ownership requirements.

Clawback Policy. The Company has adopted the Northwest Bancshares, Inc. Clawback Policy (the "Clawback Policy"), which adheres to the listing standards of Nasdaq and with Rule 10D-1under the Exchange Act. This Clawback Policy requires recoupment of certain cash and equity incentive compensation paid to or deferred by certain executives in the event the Company is required to prepare an accounting restatement due to material noncompliance with any financial reporting requirement under the federal securities laws. Under the Clawback Policy, recoupment is required if the Board determines that incentive-based compensation received by an executive exceeds the amount of incentive-based compensation that otherwise would have been received, had it been calculated based on the restated amounts.

The Clawback Policy is disclosed as an exhibit to the Company's Annual Report on Form 10-Kfor the year ended December 31, 2024.

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Employment Agreements/Change in Control Agreements.We have entered into employment agreements with Messrs. Torchio and Schosser and change in control agreements with Messrs. Betchkal, DesMarteau and Watson. These agreements are designed to give us the ability to retain the services of the designated executives while reducing, to the extent possible, unnecessary disruptions to our operations. The employment agreements with Messrs. Torchio and Schosser provide for a base salary, annual bonus payments and long-term incentive equity grants as well as severance benefits in connection with certain terminations of an executive's employment. The change in control agreements provide for a base salary, as well as severance benefits in connection with certain terminations of an executive's employment. The agreements were negotiated directly with, and recommended for approval by, the Compensation Committee. The Compensation Committee believes such agreements necessary to retain executive talent and consistent with market practice.

On September 20, 2023, as a result of Mr. Harvey's retirement announcement, the Company and Northwest Bank entered into a Retirement Agreement pursuant to which Mr. Harvey transitioned from his role as Chief Financial Officer concurrently with the appointment of Mr. Schosser as our Chief Financial Officer on March 18, 2024, and retired as Chief Operating Officer and as a director from the Company Northwest Bank on December 31, 2024. In addition, on June 17, 2024, as a result of Mr. Golding's involuntary termination by us, the Company and Northwest Bank entered into a Confidential Separation Agreement and General Release with Mr. Golding. For a more detailed discussion of these agreements and the payments that would be received by the NEOs under these agreements in connection with certain terminations of employment, see "Employment Agreements/Change in Control Agreements" and "Potential Payments to Named Executive Officers".

Impact of Accounting and Tax.In consultation with our advisors, we evaluate the tax and accounting treatment of each of our compensation programs at the time of adoption and on an annual basis to ensure that we understand the financial impact of the program. Furthermore, Section 162(m) of the Internal Revenue Code generally limits the tax deductibility of annual compensation paid by public companies for certain executive officers to $1 million. The Compensation Committee continues to have the flexibility to award compensation that is not tax deductible if it determines that such award is in the Company's best interests.

Review of Risk Related to Compensation Policies and Procedures.The Compensation Committee is responsible for the oversight of employee compensation policies and procedures, including the determination of whether any material risk is imposed on the Company from the annual cash incentive plan, long-term stock-based compensation plan and/or employment or change in control agreements. After reviewing the compensation policies and procedures, including the determination of whether any incentive/variable compensation programs encourage excessive risk taking by employees, the Compensation Committee has concluded such plans do not pose material risk to the Company.

Compensation Committee Report.The Compensation Committee has reviewed and discussed the section titled "Compensation Discussion and Analysis" with management. Based on this review and discussion, the Compensation Committee recommended to the Board that the section titled "Compensation Discussion and Analysis" be included in this Proxy Statement and incorporated into the Company's Annual Report on Form 10-Kfor the fiscal year ended December 31, 2024.

Respectfully submitted by the members of the Compensation Committee of the Board:

This report of the Compensation Committee is required by the Securities and Exchange Commission and, in accordance with the SEC's rules, will not be deemed to be part of or incorporated by reference by any general statement incorporating by reference this Proxy Statement into any filing under the Securities Act of 1933 (the "Securities Act"), or under the Exchange Act, except to the extent that we specifically incorporate this information by reference, and will not otherwise be deemed "soliciting material" or "filed" under either the Securities Act or the Exchange Act.

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Executive Compensation

Summary Compensation Table.The following table sets forth, for the three years ended December 31, 2024, certain information as to the total remuneration we paid to Mr. Torchio, who serves as our President and CEO, Mr. Schosser, who serves as our Chief Financial Officer and Mr. Harvey, who served as our former Chief Operating Officer and former Chief Financial Officer and our four other most highly compensated NEOs as of December 31, 2024.

(footnotes on following page)

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(footnotes from previous page)

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Grants of Plan-Based Awards. The following table sets forth for the fiscal year ending December 31, 2024 certain information as to grants of plan-based awards for the NEOs.

During the year ended December 31, 2024, RSUs and PSUs were awarded to each NEO under our 2022 Equity Incentive Plan. The RSUs granted are subject to time-based vesting and are listed in the column entitled "All other stock awards: number of shares or units". Awards listed under "Estimated future payouts under equity incentive plan awards" represent the number of shares of RSUs (the first line for each NEO) and PSUs (the second line for each NEO) that can be earned as described in "Compensation Discussion and Analysis-Long-Term Stock-Based Compensation". Each award of RSUs vests over three years beginning one year from the date of grant. Vesting is accelerated in the event of involuntary termination following a change in control of Northwest Bank or the Company and in the event of the recipient's death, disability or normal retirement (generally, the attainment of age 65). For a further discussion of grants made for the year ended December 31, 2024, see "Compensation Discussion and Analysis-Long-Term Stock-Based Compensation".

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Outstanding Equity Awards at Fiscal Year End. The following table sets forth information with respect to outstanding equity awards for the NEOs as of December 31, 2024. Market values are calculated using the closing price of our common stock on December 31, 2024.