Eastern Bankshares : Merger with Cambridge Bancorp and Sale of Eastern Insurance Group

Merger with and sale of

September 19, 2023

Forward-looking statements

This presentation contains "forward-looking statements" within the meaning of section 27A of the Securities Act of 1933, as amended, and section 21E of the Securities

Exchange Act of 1934, as amended. Forward-looking statements include statements regarding anticipated future events and can be identified by the fact that they do not relate strictly to historical or current facts. You can identify these statements from the use of the words "may," "will," "should," "could," "would," "plan," "potential," "estimate," "project," "believe," "intend," "anticipate," "expect," "target" and similar expressions. Forward-looking statements, by their nature, are subject to risks and uncertainties. There are many factors that could cause actual results to differ materially from expected results described in the forward-looking statements.

Factors relating to the proposed transactions that could cause or contribute to actual results differing materially from expected results include, but are not limited to, the possibility that revenue or expense synergies or the other expected benefits of one or both transactions may not materialize in the timeframe expected or at all, or may be more costly to achieve; that one or both transactions may not be timely completed, if at all; that prior to the completion of the transactions or thereafter, Eastern or Cambridge may not perform as expected due to transaction-related uncertainty or other factors; that Eastern is unable to successfully implement its integration or disposition strategies; that required regulatory, shareholder or other approvals are not obtained or other closing conditions are not satisfied in a timely manner or at all for one or both transactions; that the timing of completion of the proposed mergers are each dependent on various factors that cannot be predicted with precision at this point; reputational risks and the reaction of the companies' customers to one or both transactions; the inability to implement onboarding or transition plans and other consequences associated with the mergers; continued pressures and uncertainties within the banking industry and Eastern and Cambridge's markets, including changes in interest rates and deposit amounts and composition, adverse developments in the level and direction of loan delinquencies, charge-offs, and estimates of the adequacy of the allowance for loan losses, increased competitive pressures, asset and credit quality deterioration, and legislative, regulatory, and fiscal policy changes and related compliance costs; and diversion of management time on transaction-related issues.

These forward-looking statements are also subject to the risks and uncertainties applicable to our respective businesses generally that are disclosed in Eastern's and Cambridge's 2022 Annual Reports on Form 10-K. Eastern's and Cambridge's SEC filings are accessible on the SEC's website at www.sec.gov and on their respective corporate websites at investor.easternbank.com and ir.cambridgetrust.com. These web addresses are included as inactive textual references only. Information on these websites is not part of this document. For any forward-looking statements made in this presentation, Eastern and Cambridge claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. Except as required by law, each company specifically disclaims any obligation to update any forward-looking statements as a result of developments occurring after the date of this presentation.

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Non-GAAP financial measures

*Denotes a non-GAAP financial measure used in this presentation.

This presentation contains both financial measures based on accounting principles generally accepted in the United States ("GAAP") and non-GAAP based financial measures. Management believes that providing certain non-GAAP financial measures provides investors with information useful to their understanding financial performance, performance trends and financial position. Management utilizes these measures for internal planning and forecasting purposes, and management, as well as securities analysts, investors, and other interested parties, also use these measures to compare peer company operating performance. These non-GAAP measures should not be considered a substitute for GAAP basis measures and results. Because non-GAAP financial measures are not standardized, it may not be possible to compare these financial measures with other companies' non-GAAP financial measures having the same or similar names. A reconciliation of tangible common equity and tangible common equity to tangible assets for Cambridge Bancorp is included on pages 29 of the presentation.

This presentation also includes certain forward-looking modeled projections and estimates, including estimates of the combined proforma company's tangible book value and tangible book value per share. These metrics are dependent on variable factors including management's assumptions and modeling inputs as well as market driven factors such as interest rates, over which the Company cannot exercise control. Accordingly, reconciliations of the Company's outlook on these items cannot be readily determined in a format useful for investors and could not be made readily available. The Company has provided a summary on page 24 of the presentation that sets forth key expectations and assumptions regarding the estimated tangible book value per share impact of the proposed merger transaction.

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Additional information

Additional Information and Where to Find It

In connection with the proposed merger transaction, the Company intends to file with the SEC a Registration Statement on Form S-4 that will include a Joint Proxy Statement of the Company and Cambridge and a Prospectus of the Company (the "joint proxy statement/prospectus"), as well as other relevant documents concerning the proposed transaction. This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. INVESTORS AND SHAREHOLDERS OF THE COMPANY AND CAMBRIDGE ARE URGED TO READ THE REGISTRATION STATEMENT AND THE JOINT PROXY STATEMENT/PROSPECTUS REGARDING THE TRANSACTION WHEN IT BECOMES AVAILABLE AND EACH OTHER RELEVANT DOCUMENT FILED WITH THE SEC, AS WELL AS ANY AMENDMENT OR SUPPLEMENT TO THOSE DOCUMENTS, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION. A copy of the definitive joint proxy statement/prospectus, as well as other filings containing information about the Company and Cambridge, can be obtained without charge, at the SEC's website (http://www.sec.gov). Copies of the joint proxy statement/prospectus and the filings with the SEC that will be incorporated by reference in the joint proxy statement/prospectus can also be obtained, without charge, by directing a request to the Company's Investor Relations team via email at [e-mail] or by telephone at [phone], or to Cambridge Investor Relations via email at [e-mail] or by telephone at [phone].

Participants in the Solicitation

The Company, Cambridge, and their respective directors, executive officers and other members of management and employees may be deemed to be participants in the solicitation of proxies from the shareholders of the Company and/or Cambridge in connection with the proposed transaction under the rules of the SEC. Information regarding the Company's directors and executive officers is available in its definitive proxy statement relating to its 2023 Annual Meeting of Shareholders, which was filed with the SEC on April 3, 2023, and its Annual Report on Form 10-K for the year ended December 31, 2022, which was filed with the Commission on February 24,

2023, and other documents filed by the Company with the SEC. Information regarding Cambridge's directors and executive officers is available in its definitive proxy

statement relating to its 2023 Annual Meeting of Shareholders, which was filed with the SEC on March 16, 2023, and other documents filed by Cambridge with the SEC. Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, will be included in the joint proxy statement/prospectus and other relevant materials filed with the SEC, which may be obtained free of charge as described in the preceding paragraph.

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Today's presenters

Presenter

Bob Rivers

Chief Executive Officer and Chair of the Board of Eastern Bankshares

Denis Sheahan

Chief Executive Officer, President and Chair of the Board of Cambridge Bancorp

Jim Fitzgerald

Chief Administrative Officer, Chief Financial Officer and Treasurer of Eastern Bankshares

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