Merger Investor Presentation (December 17, 2024) Merger Investor Presentation PWB Investor Presentation – Creating Success by Delivering Solutions (November 2024) Investor Presentation

Forward-looking Statements and Additional Information

This communication is being made in respect of the proposed merger transaction involving NWBI and PWOD. This material is not a solicitation of any vote or approval of the NWBI or PWOD shareholders and is not a substitute for the proxy

statement/prospectus or any other documents that NWBI and PWOD may send to their respective shareholders in connection with the proposed transaction. This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities.

The proposed merger transaction will be submitted to the shareholders of PWOD for their consideration. In connection therewith, NWBI intends to file relevant materials with the U.S. Securities and Exchange Commission (the "SEC"), including a Registration Statement on Form S-4, which will include the proxy statement of PWOD that also will constitute a prospectus of NWBI (the "proxy statement/prospectus"), as well as other relevant documents concerning the proposed transaction. However, such materials are not currently available. The proxy statement/prospectus will be mailed to the shareholders of PWOD when available. BEFORE MAKING ANY VOTING OR INVESTMENT DECISIONS, INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE REGISTRATION STATEMENT AND THE PROXY STATEMENT/PROSPECTUS REGARDING THE PROPOSED TRANSACTION AND ANY OTHER RELEVANT DOCUMENTS THAT MAY BE FILED WITH THE SEC AND ANY AMENDMENTS OR SUPPLEMENTS TO THOSE DOCUMENTS CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT NWBI, PWOD, THE PROPOSED TRANSACTION AND RELATED MATTERS. Shareholders are also urged to carefully review and consider NWBI's and PWOD's public filings with the SEC, including, but not limited to, its proxy statements, its Annual Reports on Form 10-K, its Quarterly Reports on Form 10-Q and its Current Reports on Form 8-K. Investors and security holders may obtain free copies of the proxy statement/prospectus, any amendments or supplements thereto and other documents containing important information about NWBI or PWOD and/or the proposed transaction, once such documents are filed with the SEC, at the SEC's website at www.sec.gov. In addition, copies of the documents filed with the SEC by NWBI, including the proxy statement/prospectus and the SEC filings that will be incorporated by reference in the proxy statement/prospectus, will be available free of charge on the NWBI's website at www.northwest.bank under the heading "Investor Relations."

Participants in the Solicitation

NWBI, PWOD and certain of their respective directors, executive officers and other members of management and employees may, under the SEC's rules, be deemed to be participants in the solicitation of proxies in connection with the proposed transaction. Information about the directors and executive officers of NWBI is set forth in its proxy statement for its 2024 annual meeting of shareholders, which was filed with the SEC on March 8, 2024, its annual report on Form 10-K for the fiscal year ended December 31, 2023, which was filed with the SEC on February 23, 2024, and in other documents filed with the SEC, each of which can be obtained free of charge from the sources indicated above. Information about the directors and executive officers of PWOD is set forth in its proxy statement for its 2024 annual meeting of shareholders, which was filed with the SEC on March 26, 2024, its annual report on Form 10-K for the fiscal year ended December 31, 2023, which was filed with the SEC on March 13, 2024, and in other documents filed with the SEC, each of which can be obtained free of charge from the sources indicated above. Additional information regarding the participants in the proxy solicitation, including a description of their direct and indirect interests, by security holdings or otherwise, will be contained in the proxy statement/prospectus and other relevant materials to be filed with the SEC when they become available. Free copies of these documents may be obtained as described in the preceding paragraph.

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Overview of Penns Woods Bancorp, Inc.

A Noteworthy Transaction: Significant and Financially Appealing

Geographically Attractive Combined Company

Transaction Structure

Transaction Structure

Transaction Value

& Multiples1,2,3

Personnel and

Projected Ownership

Diligence, Expected Timing & Approvals

• Northwest Bancshares, Inc. to acquire 100% of Penns Woods Bancorp, Inc. outstanding common stock
• At closing Jersey Shore State Bank and Luzerne Bank will merge with and into Northwest Bank
• 100% stock consideration
• Fixed exchange ratio of 2.385x NWBI shares for each PWOD share
• Outstanding stock options to be exchanged for cash
• Aggregate Transaction Value: approximately $270.4 million
• Per Share Consideration: approximately $34.44
• Price / Tangible Book Value Per Share of 139.0%
• Price / LTM Core EPS of 12.8x
• 0.91x Pay-to-Trade ratio
• Richard Grafmyre, CEO of PWOD, to be added to the NWBI board for a combined total of 12
• Projected ownership of approximately 87.6% NWBI / 12.4% PWOD
• Conducted extensive due diligence process across all business functions
• Subject to the receipt of PWOD shareholder approvals and required regulatory approvals and other customary closing conditions
• Anticipated closing during the third quarter of 2025

1. Based on PWOD common shares outstanding of 7,554,488
2. Based on NWBI's closing stock price of $14.44 per share, as of December 16, 2024
3. Based on PWOD outstanding stock options of 1,094,000 with a weighted average strike price of $25.13 to be exchanged for cash

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Financial Assumptions

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