Filed Pursuant to Rule 424(b)(3)​

 Registration No. 333-229506​

MERGER PROPOSED — YOUR VOTE IS VERY IMPORTANT

Dear SI Financial Group, Inc. Stockholder:

On December 11, 2018, SI Financial Group, Inc. (which we refer to as “SI Financial”) entered into an Agreement and Plan of Merger (which we refer to as the “merger agreement”) with Berkshire Hills Bancorp, Inc. (which we refer to as “Berkshire Hills Bancorp”). Under the merger agreement, SI Financial will merge with and into Berkshire Hills Bancorp, with Berkshire Hills Bancorp as the surviving corporation, in a transaction that we refer to as the “merger”. Immediately following the merger, SI Financial’s wholly-owned subsidiary, Savings Institute Bank and Trust, will merge with and into Berkshire Hills Bancorp’s wholly-owned subsidiary, Berkshire Bank, with Berkshire Bank as the surviving bank.

Under the terms of the merger agreement, each outstanding share of common stock, par value $0.01 per share, of SI Financial (which we refer to as “SI Financial common stock”) will be converted into the right to receive 0.48 shares (which we refer to as the “merger consideration”) of common stock, par value $0.01 per share of Berkshire Hills Bancorp (which we refer to as “Berkshire Hills Bancorp common stock”).

Shares of Berkshire Hills Bancorp common stock are listed on the New York Stock Exchange under the symbol “BHLB.” Shares of SI Financial common stock are listed on the Nasdaq Global Market under the symbol “SIFI.” Based on the closing price of Berkshire Hills Bancorp common stock on the New York Stock Exchange on December 11, 2018, the last trading day before public announcement of the merger, the value of the per share merger consideration payable to holders of SI Financial common stock would be $15.02. Based on the closing price of Berkshire Hills Bancorp common stock on the New York Stock Exchange on February 19, 2019, the last practicable trading date before the date of the attached proxy statement/prospectus, the value of the per share merger consideration payable to holders of SI Financial common stock would be $14.68. You should obtain current market quotations for both Berkshire Hills Bancorp common stock and SI Financial common stock. Based on the number of shares of SI Financial common stock outstanding and the number of shares of SI Financial common stock issuable pursuant to outstanding SI Financial stock options, in each case as of February 19, 2019, the total number of shares of Berkshire Hills Bancorp common stock expected to be issued in connection with the merger is approximately 5,919,478. In addition, based on the number of issued and outstanding shares of Berkshire Hills Bancorp common stock and SI Financial common stock on February 19, 2019, and based on the exchange ratio of 0.48, holders of shares of SI Financial common stock as of immediately prior to the closing of the merger will hold, in the aggregate, approximately 11.5% of the issued and outstanding shares of Berkshire Hills Bancorp common stock immediately following the closing of the merger (without giving effect to any Berkshire Hills Bancorp common stock held by SI Financial’s stockholders prior to the merger).

Although the number of shares of Berkshire Hills Bancorp common stock that holders of SI Financial common stock will be entitled to receive is fixed, the market value of the merger consideration will fluctuate with the market price of Berkshire Hills Bancorp common stock and will not be known at the time SI Financial stockholders vote on the merger. However, SI Financial has the right to terminate the merger agreement if, at any time during a five-day period commencing on the tenth day prior to closing, the average closing price of Berkshire Hills Bancorp common stock over the 20 consecutive trading days prior to the tenth day prior to closing (i) is less than $24.99 and (ii) fails to meet certain comparison thresholds relative to the Nasdaq Bank Index, as further described in the accompanying proxy statement/prospectus. If SI Financial elects to exercise this termination right, then Berkshire Hills Bancorp has the option to override the proposed termination by increasing the exchange ratio to a level that would eliminate the effects of either of the two requirements of this termination right.

SI Financial is holding a special meeting for its stockholders to vote on the proposals necessary to complete the merger. The merger cannot be completed unless a majority of the shares of common stock of SI Financial outstanding and entitled to vote at the special meeting vote to approve the merger agreement. At the special meeting, SI Financial’s stockholders will also be asked to vote on (i) the non-binding, advisory proposal to approve the compensation that certain named executive officers of SI Financial may receive that is based on or otherwise relates to the merger and (ii) a proposal to approve the adjournment of the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the merger proposal. The special meeting of stockholders of SI Financial will be held at Savings Institute Bank and Trust Company Financial Center, 579 North Windham Road, North Windham, Connecticut 06256 on April 2, 2019 at 9:00 a.m., Eastern Time. SI Financial’s board of directors has unanimously determined that the merger and the merger agreement are in the best interests of SI Financial and its stockholders and unanimously recommends that you vote “FOR” the approval of the merger agreement and “FOR” the other matters to be considered at the special meeting.

Whether or not you plan to attend the special meeting, please take the time to vote by completing the enclosed proxy card and mailing it in the enclosed envelope. To ensure your representation at the special meeting, please promptly complete sign, date and return the enclosed proxy card in the enclosed postage-paid envelope or by submitting a proxy through the Internet or by telephone as described on the enclosed instructions. If you hold your shares in “street name,” you should instruct your broker, bank or other nominee how to vote in accordance with the voting instruction form you receive from your broker, bank or other nominee.

The accompanying document is being delivered to SI Financial stockholders as Berkshire Hills Bancorp’s prospectus for its offering of Berkshire Hills Bancorp common stock in connection with the merger, and as a proxy statement for the solicitation of proxies from SI Financial stockholders to vote for the approval of the merger agreement.

This proxy statement/prospectus provides you with detailed information about the proposed merger. It also contains or references information about Berkshire Hills Bancorp and SI Financial and related matters. You are encouraged to read this document carefully. In particular, you should read the “Risk Factors” section beginning on page 14 for a discussion of certain risks you should consider in evaluating the proposed merger and how it will affect you.

Voting procedures are described in this proxy statement/prospectus. Your vote is important and I urge you to cast it promptly.

Sincerely,

/s/ Rheo A. Brouillard

Rheo A. Brouillard
President and Chief Executive Officer

This proxy statement/prospectus is dated February 25, 2019, and is first being mailed to SI Financial stockholders on or about February 26, 2019.

ADDITIONAL INFORMATION

This proxy statement/prospectus incorporates by reference important business and financial information about Berkshire Hills Bancorp and SI Financial from documents that Berkshire Hills and SI Financial have previously filed with the Securities and Exchange Commission (which we refer to as the “SEC”) that are not included in or delivered with the proxy statement/prospectus. You can obtain any of the documents filed with or furnished to the SEC by Berkshire Hills Bancorp or SI Financial at no cost from the SEC’s website at www.sec.gov. You will also be able to obtain these documents, free of charge, from Berkshire Hills Bancorp at www.ir.berkshirebank.com or from SI Financial at www.mysifi.com. These documents are also available without charge to you upon written or oral request to the applicable company’s principal executive offices. The respective addresses and telephone numbers of such principal executive offices are listed below:

To obtain timely delivery of these documents, you must request them no later than March 26, 2019 in order to receive them before SI Financial’s special meeting of stockholders.

For a more detailed description of the information incorporated by reference into the proxy statement/prospectus and how you may obtain it, see the section entitled “Where You can Find More Information.”

You should rely only on the information contained in, or incorporated by reference into, the proxy statement/prospectus. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, the proxy statement/prospectus. The proxy statement/prospectus is dated February 25, 2019, and you should assume that the information in the proxy statement/prospectus is accurate only as of such date unless information specifically indicates that another date applies.

The proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction in which or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

SI FINANCIAL GROUP, INC.
803 MAIN STREET
WILLIMANTIC, CONNECTICUT 06226

NOTICE OF THE SPECIAL MEETING OF STOCKHOLDERS
TO BE HELD ON APRIL 2, 2019

NOTICE IS HEREBY GIVEN that a special meeting of the stockholders (which we refer to as the “special meeting”) of SI Financial Group, Inc. (which we refer to as “SI Financial”) will be held on April 2, 2019 at 9:00 a.m., Eastern Time, at Savings Institute Bank and Trust Company Financial Center, 579 North Windham Road, North Windham, Connecticut 06256, for the following purposes:

1.

To consider and vote upon a proposal to approve the Agreement and Plan of Merger, dated as of December 11, 2018 (which we refer to as the “merger agreement”), by and between Berkshire Hills Bancorp, Inc. and SI Financial and the transactions contemplated thereby, in (which proposal we refer to as the “merger proposal”);

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2.

To consider and vote upon an advisory, non-binding proposal to approve compensation payable to the named executive officers of SI Financial in connection with the merger (which proposal we refer to as the “merger-related compensation proposal”); and

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3.

To approve one or more adjournments of the special meeting if necessary or appropriate to solicit additional proxies if there are not sufficient votes to approve the merger proposal (which proposal we refer to as the “adjournment proposal”).

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The merger is described in more detail in this proxy statement/prospectus, which you should read carefully in its entirety before voting. A copy of the merger agreement is attached as Appendix A to this proxy statement/prospectus. Only SI Financial stockholders of record as of the close of business on February 19, 2019, are entitled to notice of and to vote at the special meeting or any adjournments or postponements of the special meeting.

The affirmative vote of the holders of a majority of the outstanding shares of SI Financial common stock is required to approve the merger proposal. The affirmative vote of the holders of at least a majority of the votes cast at the special meeting is required to approve each of the merger-related compensation proposal and the adjournment proposal.

SI Financial’s board of directors unanimously recommends that you vote “FOR” the merger proposal, “FOR” the merger-related compensation proposal, and “FOR” the adjournment proposal.

To ensure your representation at the special meeting, please follow the voting procedures described in the accompanying proxy statement/prospectus and on the enclosed proxy card. This will not prevent you from voting in person, but it will help to secure a quorum and allow your shares to be voted should anything prevent your attendance in person. Your proxy may be revoked at any time before it is voted by following the instructions provided in the proxy statement/prospectus.

Willimantic, Connecticut
February 26, 2019

YOUR VOTE IS IMPORTANT!

WHETHER OR NOT YOU EXPECT TO ATTEND THE SPECIAL MEETING IN PERSON, PLEASE SUBMIT YOUR PROXY AS PROMPTLY AS POSSIBLE BY COMPLETING, SIGNING AND DATING THE ENCLOSED PROXY CARD AND RETURNING IT IN THE POSTAGE-PAID ENVELOPE PROVIDED. If your shares are held in the name of a bank, broker or other nominee, please follow the instructions on the voting instruction card furnished to you by such record holder.

If you have any questions concerning the merger or other matters to be considered at the special meeting, would like additional copies of this proxy statement/prospectus or need help voting your shares, please contact SI Financial’s proxy solicitor:

Morrow Sodali LLC
470 West Avenue
Stamford, Connecticut 06902
Telephone (toll-free): (800) 662-5200
Banks and brokers may call collect: (203) 658-9400

PLEASE DO NOT SEND STOCK CERTIFICATES WITH THE PROXY CARD. YOU WILL BE SENT SEPARATE INSTRUCTIONS REGARDING THE SURRENDER OF YOUR STOCK CERTIFICATES.

TABLE OF CONTENTS

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QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING

The following are answers to certain questions that you may have regarding the merger and the special meeting. We urge you to read carefully the remainder of this proxy statement/prospectus because the information in this section may not provide all the information that might be important to you in determining how to vote. Additional important information is also contained in the appendices to, and the documents incorporated by reference in, this proxy statement/prospectus.

Q:

WHY AM I RECEIVING THIS DOCUMENT?

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A.

Berkshire Hills Bancorp, Inc. (which we refer to as “Berkshire Hills Bancorp”) and SI Financial Group, Inc. (which we refer to as “SI Financial”) have agreed to combine under the terms of an Agreement and Plan of Merger dated as of December 11, 2018 (which we refer to as the “merger agreement”), that is described in this proxy statement/prospectus. A copy of the merger agreement is attached to this proxy statement/prospectus as Appendix A. In order to complete the merger of SI Financial with and into Berkshire Hills Bancorp (which we refer to as the “merger”), the stockholders of SI Financial must vote to approve the merger agreement. SI Financial will hold a special meeting of its stockholders to obtain these approvals. This proxy statement/prospectus contains important information about the merger, the merger agreement, the special meeting of SI Financial stockholders, and other related matters, and you should read it carefully.

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The merger cannot be completed unless SI Financial stockholders vote to approve the merger agreement. With this proxy statement/prospectus, SI Financial’s board of directors is soliciting proxies from SI Financial stockholders to obtain this approval at the special meeting discussed below.

Q:

WHAT WILL SI FINANCIAL STOCKHOLDERS RECEIVE IN THE MERGER?

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A:

If the merger proposal is approved and the merger is subsequently completed, SI Financial stockholders will receive 0.48 shares of Berkshire Hills Bancorp common stock for each share of SI Financial common stock held immediately prior to the merger. Berkshire Hills Bancorp will not issue any fractional shares of Berkshire Hills Bancorp common stock in the merger. SI Financial stockholders who would otherwise be entitled to a fractional share of Berkshire Hills Bancorp common stock upon the completion of the merger will instead receive an amount in cash equal to the product of  (i) the fraction of a share of Berkshire Hills Bancorp common stock to which a SI Financial stockholder would otherwise be entitled multiplied by (ii) the average of the daily closing sale prices of Berkshire Hills Bancorp common stock as reported on the New York Stock Exchange for the ten consecutive trading days ending on the third business day prior to the closing date of the merger.

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Q:

HOW WILL THE MERGER AFFECT SI FINANCIAL STOCK OPTIONS?

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A:

At the effective time of the merger, all outstanding and unexercised options to purchase SI Financial common stock will fully vest and be converted into options to purchase a number of shares of Berkshire Hills Bancorp common stock (rounded down to the nearest whole share) determined by multiplying (i) the number of shares of SI Financial common stock subject to such SI Financial stock option immediately prior to the effective time by (ii) 0.48; and the exercise price per share of the new option will be equal to the quotient obtained by dividing (a) the per share exercise price for the shares of SI Financial common stock subject to such SI Financial option by (b) 0.48 (rounded up to the nearest whole cent).

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Q:

WILL THE VALUE OF THE MERGER CONSIDERATION CHANGE BETWEEN THE DATE OF THIS PROXY STATEMENT/PROSPECTUS AND THE TIME THAT THE MERGER IS COMPLETED?

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A:

Yes. Although the exchange ratio is fixed, the value of the merger consideration will fluctuate between the date of this proxy statement/prospectus and the completion of the merger based on the market value of Berkshire Hills Bancorp common stock. Any change in the market price of Berkshire Hills Bancorp common stock after the date of this proxy statement/prospectus will change the value of the merger consideration that SI Financial stockholders will receive.

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Q:

WHAT WILL HAPPEN TO SI FINANCIAL AS A RESULT OF THE MERGER?

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A:

If the merger is completed, SI Financial will merge with and into Berkshire Hills Bancorp, and SI Financial’s separate corporate existence will cease to exist. Immediately following the merger, Savings Institute Bank and Trust Company, a Connecticut savings bank and wholly owned subsidiary of SI Financial (which we refer to as “Savings Institute Bank and Trust”), will merge with and into Berkshire Bank, a Massachusetts trust company and wholly owned subsidiary of Berkshire Hills Bancorp, with Berkshire Bank being the surviving bank, in a transaction we refer to as the “bank merger”).

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Q:

WHEN WILL THE MERGER BE COMPLETED?

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A:

We expect the merger will be completed when all of the conditions to completion contained in the merger agreement are satisfied or waived, including the receipt of required regulatory approvals and the approval of the merger agreement by SI Financial stockholders at the special meeting. We currently expect to complete the merger in the second quarter of 2019. However, because fulfillment of some of the conditions to completion of the merger, such as the receipt of required regulatory approvals, is not entirely within our control, we cannot predict the actual timing of the completion of the merger.

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Q:

WHAT HAPPENS IF THE MERGER IS NOT COMPLETED?

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A:

If the merger is not completed, SI Financial stockholders will not receive any consideration for their shares of common stock in connection with the merger. Instead, SI Financial will remain an independent company and its common stock will continue to be listed and traded on the Nasdaq Global Market. Under specified circumstances, SI Financial may be required to pay to Berkshire Hills Bancorp a fee with respect to the termination of the merger agreement. For more information, please review the sections entitled “Terminating the Merger Agreement” and “Termination Fee” beginning on pages 82 and 83.

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Q:

WHERE CAN I FIND MORE INFORMATION ABOUT BERKSHIRE HILLS BANCORP AND SI FINANCIAL?

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A:

You can find more information about Berkshire Hills Bancorp and SI Financial from the various sources described under the section entitled “Where You Can Find More Information” at the end of this proxy statement/prospectus.

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Q:

WHEN AND WHERE IS THE SPECIAL MEETING?

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A:

SI Financial will hold a special meeting of its stockholders on April 2, 2019, at 9:00 a.m., Eastern Time, at Savings Institute Bank and Trust Company Financial Center, 579 North Windham Road, North Windham, Connecticut 06256.

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Q:

WHO CAN VOTE AT THE SPECIAL MEETING?

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A:

Holders of record of SI Financial common stock at the close of business on February 19, 2019, the record date for the special meeting, are entitled to vote at the special meeting.

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Q:

HOW MANY VOTES MUST BE REPRESENTED IN PERSON OR BY PROXY AT THE SI FINANCIAL SPECIAL MEETING TO HAVE A QUORUM?

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A:

The holders of a majority of all of the shares of SI Financial common stock entitled to vote at the special meeting, present in person or represented by proxy, will constitute a quorum at the special meeting.

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Q:

WHAT MATTERS ARE SI FINANCIAL STOCKHOLDERS BEING ASKED TO APPROVE AT THE SPECIAL MEETING?

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A:

SI Financial stockholders are being asked to vote on the following:

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A proposal to approve the merger agreement, a copy of which is attached as Appendix A, and the transactions contemplated thereby, which we refer to as the “merger proposal”;

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A proposal to approve, on an advisory, non-binding basis, compensation payable to the named executive officers of SI Financial in connection with the merger, which we refer to as the merger-related compensation proposal; and

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A proposal to approve one or more adjournments of the special meeting if necessary or appropriate to solicit additional proxies if there are not sufficient votes to approve the merger proposal, which we refer to as the “adjournment proposal.”

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Q:

WHAT VOTE BY SI FINANCIAL STOCKHOLDERS IS REQUIRED TO APPROVE THE SPECIAL MEETING PROPOSALS?

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A:

Merger Proposal:   Approval of the merger proposal requires the affirmative vote of a majority of the outstanding shares of SI Financial common stock entitled to vote on the merger agreement. Abstentions and broker non-votes will have the same effect as a vote against the merger proposal.

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Merger-Related Compensation Proposal and Adjournment Proposal:   Approval of the merger-related compensation proposal and the adjournment proposal each requires the affirmative vote of a majority of the votes cast on the proposal. Abstentions and broker non-votes will not affect whether either proposal is approved.

As of the record date for the special meeting, directors and senior executive officers of SI Financial, together with their affiliates, had sole or shared voting power over approximately 3.3% of the SI Financial common stock outstanding and entitled to vote at the special meeting. Pursuant to the terms of the merger agreement, each of the directors and certain of the senior executive officers of SI Financial have entered into voting agreements with Berkshire Hills Bancorp pursuant to which they have agreed to vote an aggregate of 351,882 shares of SI Financial common stock in favor of the merger proposal at the special meeting.

Q:

HOW MAY THE SI FINANCIAL STOCKHOLDERS VOTE THEIR SHARES FOR THE SPECIAL MEETING PROPOSALS PRESENTED IN THIS PROXY STATEMENT/​PROSPECTUS?

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A:

SI Financial stockholders may vote by completing, signing, dating and returning the proxy card in the enclosed prepaid return envelope, or by following the telephone or Internet voting instructions on the proxy card as soon as possible, or by attending the special meeting and voting in person. This will enable your shares to be represented and voted at the special meeting. If your stock is held in “street name,” you will receive instructions from your broker, bank or other nominee that you must follow to have your shares voted. Your broker, bank or other nominee may allow you to deliver your voting instructions via the telephone or the Internet. Please review the proxy card or instruction form provided by your broker, bank or other nominee that accompanies this proxy statement/prospectus.

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Q:

WILL A BROKER OR BANK HOLDING SHARES IN “STREET NAME” FOR A SI FINANCIAL STOCKHOLDER AUTOMATICALLY VOTE THOSE SHARES FOR THE STOCKHOLDER AT THE SPECIAL MEETING?

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A:

No. A broker or bank WILL NOT be able to vote your shares with respect to the merger proposal without first receiving instructions from you on how to vote. If your shares are held in “street name,” you will receive separate voting instructions with your proxy materials. It is important that you provide timely instruction to your broker or bank to ensure that all shares of SI Financial common stock that you own are voted at the special meeting. The failure of a SI Financial stockholder whose shares of SI Financial common stock are held in “street name” to give voting instructions to the broker or bank will have the same effect as a vote “AGAINST” the merger proposal.

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Q:

IF I AM A PARTICIPANT IN SI FINANCIAL’S ESOP OR SI FINANCIAL’S 401(K) PLAN, HOW WILL SHARES OWNED THROUGH SUCH PLANS BE VOTED?

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A:

If you participate in the Savings Institute Bank and Trust Company Employee Stock Ownership Plan (which we refer to as the “Savings Institute ESOP”) or if you hold shares of SI Financial common stock through the Savings Institute Bank and Trust Company Profit Sharing and 401(k) Plan (which we refer to as the “Savings Institute 401(k) Plan”), you will receive a voting instruction card for each

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plan that reflects all shares you may direct the trustees to vote on your behalf under the plans. Under the terms of the Savings Institute ESOP, the Savings Institute ESOP trustee votes all allocated shares of SI Financial common stock held by the Savings Institute ESOP as directed by the plan participants. The Savings Institute ESOP trustee, subject to the exercise of its fiduciary duties, will vote all unallocated shares of SI Financial common stock held by the Savings Institute ESOP and allocated shares for which no voting instructions are received in the same proportion as shares for which it has received timely voting instructions.

Under the terms of the Savings Institute 401(k) Plan, a participant is entitled to direct the trustee how to vote the shares of SI Financial common stock held in the SI Financial Stock Fund and credited to his or her Savings Institute 401(k) Plan account. The trustee will vote all shares for which no directions are given or for which instructions were not timely received in the same proportion as shares for which the trustee received voting instructions.

Q:

WILL SI FINANCIAL STOCKHOLDERS BE ABLE TO VOTE THEIR SHARES AT THE SPECIAL MEETING IN PERSON?

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A:

Yes. Submitting a proxy will not affect the right of any stockholder to vote in person at the special meeting. If you hold your shares in “street name” and wish to attend the special meeting, you must ask your broker or bank how to vote those shares in person at the special meeting.

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Q:

MAY A SI FINANCIAL STOCKHOLDER CHANGE OR REVOKE HIS OR HER VOTE AFTER SUBMITTING A PROXY?

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A:

Yes. If you have not voted through your broker, you can change your vote by:

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providing written notice of revocation to Laurie L. Gervais, Corporate Secretary, SI Financial Group, Inc., which must be provided by the time the special meeting begins;

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submitting a new proxy card (any earlier proxies will be revoked automatically); or

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attending the special meeting and voting in person. Any earlier proxy will be revoked. However, simply attending the special meeting without voting will not revoke your proxy.

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If you have instructed a broker to vote your shares, you must follow your broker’s directions to change your vote.

Q:

WHAT SHOULD A SI FINANCIAL STOCKHOLDER DO IF HE OR SHE RECEIVES MORE THAN ONE SET OF VOTING MATERIALS?

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A:

As a SI Financial stockholder, you may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold your SI Financial shares in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold SI Financial shares. In addition, if you are a holder of record and your SI Financial shares are registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this proxy statement/prospectus in the section entitled “Special Meeting of SI Financial Stockholders.”

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Q:

DO SI FINANCIAL STOCKHOLDERS HAVE DISSENTERS’ OR APPRAISAL RIGHTS?

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A:

No. Under the Maryland General Corporation Law (the “MGCL”) and the articles of incorporation of SI Financial, SI Financial stockholders do not have appraisal rights in connection with the merger.

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Q:

WHAT DOES SI FINANCIAL’S BOARD OF DIRECTORS RECOMMEND WITH RESPECT TO THE THREE PROPOSALS?

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A:

SI Financial’s board of directors unanimously (i) determined that the merger agreement and the merger are in the best interests of SI Financial and its stockholders, (ii) approved the merger agreement and recommended that the SI Financial stockholders approve the merger agreement, and (iii) directed

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that the merger agreement be submitted for consideration by the SI Financial stockholders. Accordingly, the SI Financial board of directors unanimously recommends that SI Financial stockholders vote “FOR” the merger proposal, “FOR” the merger-related compensation proposal and “FOR” the adjournment proposal.

Q:

WHAT ARE THE TAX CONSEQUENCES OF THE MERGER TO SI FINANCIAL STOCKHOLDERS?

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A:

It is a condition to the completion of the merger that Berkshire Hills Bancorp and SI Financial receive written opinions from their respective counsel to the effect that the merger will be treated as a “reorganization” within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended, which we refer to as the “Internal Revenue Code.” Subject to the limitations and qualifications described in the section entitled “The Merger — Material U.S. Federal Income Tax Consequences of the Merger,” if you are a United States holder of SI Financial common stock, generally you will not recognize any gain or loss with respect to the exchange of shares of SI Financial common stock for shares of Berkshire Hills Bancorp common stock in the merger. However, SI Financial stockholders generally will recognize gain or loss with respect to cash received in lieu of fractional shares of Berkshire Hills Bancorp common stock that the SI Financial stockholders would otherwise be entitled to receive.

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You should read “The Merger — Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 60 of this proxy statement/prospectus for more information about the United States federal income tax consequences of the merger. Tax matters can be complicated and the tax consequences of the merger to you will depend on your particular tax situation. You should consult your tax advisor to determine the tax consequences of the merger to you.

Q:

ARE THERE RISKS INVOLVED IN UNDERTAKING THE MERGER?

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A:

Yes. You should read and carefully consider the risk factors set forth in the section of this proxy statement/prospectus entitled “Risk Factors” beginning on page 14.

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Q:

WHY ARE SI FINANCIAL STOCKHOLDERS BEING ASKED TO APPROVE, ON AN ADVISORY, NON-BINDING BASIS, CERTAIN MERGER-RELATED EXECUTIVE COMPENSATION?

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A:

U.S. federal securities laws require SI Financial to seek an advisory, non-binding vote with respect to certain payments that may be made to SI Financial’s named executive officers in connection with the merger.

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Q:

WHAT WILL HAPPEN IF SI FINANCIAL STOCKHOLDERS DO NOT APPROVE THE MERGER-RELATED COMPENSATION PROPOSAL AT THE SPECIAL MEETING?

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A:

The vote with respect to the merger-related compensation proposal is an advisory vote and will not be binding on SI Financial. Therefore, if the merger proposal is approved by SI Financial’s stockholders, the merger-related compensation may still be paid to the SI Financial named executive officers if and to the extent required or allowed under applicable law even if SI Financial’s stockholders do not approve the merger-related compensation proposal.

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Q:

WILL THE MERGER-RELATED COMPENSATION BE PAID IF THE MERGER IS NOT CONSUMMATED?

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A:

No. Payment of the merger-related compensation is contingent upon the consummation of the merger.

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Q:

SHOULD SI FINANCIAL STOCKHOLDERS SEND IN THEIR STOCK CERTIFICATES NOW?

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A:

No. SI Financial stockholders SHOULD NOT send in any stock certificates now. If the merger is approved, transmittal materials, with instructions for their completion, will be provided to SI Financial stockholders under separate cover and the stock certificates should be sent at that time.

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Q:

WHAT SHOULD I DO IF I HOLD MY SHARES OF SI FINANCIAL COMMON STOCK IN BOOK-ENTRY FORM?

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A:

You are not required to take any special additional actions if your shares of SI Financial common stock are held in book-entry form. Promptly following the completion of the merger, shares of SI Financial common stock held in book-entry form automatically will be exchanged for shares of Berkshire Hills Bancorp common stock in book-entry form and cash to be paid in exchange for fractional shares, if any.

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Q:

WHAT HAPPENS IF I SELL MY SHARES OF SI FINANCIAL COMMON STOCK BEFORE THE SPECIAL MEETING?

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A:

The record date for SI Financial stockholders entitled to vote at the special meeting is earlier than both the date of the special meeting and the completion of the merger. If you transfer your shares of SI Financial common stock after the record date but before the special meeting, you will, unless special arrangements are made, retain your right to vote at the special meeting but will transfer the right to receive the merger consideration to the person to whom you transfer your shares.

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Q:

WHAT DO SI FINANCIAL STOCKHOLDERS NEED TO DO NOW?

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A:

After carefully reading and considering the information contained in this proxy statement/prospectus, we are requesting you vote by mail, by telephone, by Internet or by attending the special meeting and voting in person. If you choose to vote by mail, you should complete, sign, date and promptly return the enclosed proxy card. The proxy card will instruct the persons named on the proxy card to vote your SI Financial shares at the special meeting as you direct. If you sign and send in a proxy card and do not indicate how you wish to vote, your proxy will be voted “FOR” each of the special meeting proposals. Alternatively, you can follow the telephone or Internet voting instructions on your proxy card.

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Q:

WHO CAN HELP ANSWER MY QUESTIONS?

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A:

If you have any questions about the merger or the special meeting, or if you need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact SI Financial’s proxy solicitor, Morrow Sodali LLC, at (800) 662-5200 (for stockholders) or (203) 658-9400 (for banks and brokers).

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6

7

​

​

​

Berkshire Hills Bancorp Common Stock

​

​

SI Financial Common Stock

​

​

Implied Value of Merger Consideration

​

December 11, 2018

​

​

​

$

31.29

​

​

​

​

$

13.03

​

​

​

​

$

15.02

​

​

February 19, 2019

​

​

​

$

30.59

​

​

​

​

$

14.42

​

​

​

​

$

14.68

​

​

8

​

9

​

10

11

12

13

RISK FACTORS

In addition to the other information contained in or incorporated by reference into this proxy statement/​prospectus, including the matters addressed under the section “Cautionary Statement About Forward-Looking Statements” beginning on page 20, you should consider carefully the risk factors described below, in deciding how to vote. You should also read and consider the risk factors associated with the business of Berkshire Hills Bancorp and SI Financial because these risk factors may affect the operations and financial results of the combined company. These risk factors may be found in the Berkshire Hills Bancorp Quarterly Report on Form 10-Q for the nine months ended September 30, 2018, the Berkshire Hills Bancorp Annual Report on Form 10-K for the fiscal year ended December 31, 2017, the SI Financial Quarterly Report on Form 10-Q for the nine months ended September 30, 2018, and the SI Financial Annual Report on Form 10-K for the fiscal year ended December 31, 2017.

Because the market price of Berkshire Hills Bancorp common stock will fluctuate, SI Financial stockholders cannot be certain of the market value of the merger consideration they will receive.

Upon completion of the merger, each share of SI Financial common stock will be converted into the right to receive 0.48 shares of Berkshire Hills Bancorp common stock. There will be no adjustment to the exchange ratio (except for adjustments to reflect the effect of any stock split, reverse stock split, stock dividend, recapitalization, reclassification or other similar transaction with respect to Berkshire Hills Bancorp common stock), and SI Financial does not have a right to terminate the merger agreement based upon changes in the market price of Berkshire Hills Bancorp common stock, subject to the limited exception described below. Accordingly, the dollar value of Berkshire Hills Bancorp common stock that SI Financial stockholders will receive upon completion of the merger will depend upon the market value of Berkshire Hills Bancorp common stock at the time of completion of the merger, which may be lower or higher than the closing price of Berkshire Hills Bancorp common stock on the last full trading day preceding public announcement that Berkshire Hills Bancorp and SI Financial entered into the merger agreement, the last full trading day prior to the date this proxy statement/prospectus was mailed or the date of the special meeting. The market values of Berkshire Hills Bancorp common stock and SI Financial common stock have varied since Berkshire Hills Bancorp and SI Financial entered into the merger agreement and will continue to vary in the future due to changes in the business, operations or prospects of Berkshire Hills Bancorp and SI Financial, market assessments of the merger, regulatory considerations, market and economic considerations, and other factors, most of which are beyond Berkshire Hills Bancorp’s and SI Financial’s control. Accordingly, at the time of the special meeting, SI Financial stockholders will not necessarily know or be able to calculate the value of the stock consideration they would be entitled to receive upon completion of the merger. You should obtain current market quotations for shares of Berkshire Hills Bancorp common stock and for shares of SI Financial common stock. See “Market Price and Dividend Information” on page 32 for ranges of historic market prices of Berkshire Hills Bancorp common stock and SI Financial common stock.

If, at any time during the five-day period starting on the tenth day prior to closing, the average closing price of Berkshire Hills Bancorp common stock for the twenty-trading day period ending on such date is less than $24.99, and since the date of the merger agreement Berkshire Hills Bancorp common stock has underperformed the Nasdaq Bank Index by more than 20 percentage points, SI Financial may elect to terminate the merger agreement. If SI Financial provides notice of its intent to terminate, Berkshire Hills Bancorp will have the option of paying additional consideration, as specified in the merger agreement, in order to proceed with the merger.

SI Financial will be subject to business uncertainties and contractual restrictions while the merger is pending.

Uncertainty about the effect of the merger on employees and customers may have an adverse effect on SI Financial. These uncertainties may impair SI Financial’s ability to attract, retain and motivate key personnel until the merger is completed, and could cause customers and others who deal with SI Financial to seek to change existing business relationships with SI Financial. SI Financial employee retention and recruitment may be particularly challenging prior to the effective time of the merger, as employees and prospective employees may experience uncertainty about their future roles with the combined company.

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The pursuit of the merger and the preparation for the integration may place a significant burden on management and internal resources. Any significant diversion of management attention away from ongoing business and any difficulties encountered in the transition and integration process could affect SI Financial’s financial results. In addition, the merger agreement requires that SI Financial operate in the usual, regular and ordinary course of business and restricts SI Financial from taking certain actions prior to the effective time of the merger or termination of the merger agreement without Berkshire Hills Bancorp’s consent in writing. These restrictions may prevent SI Financial from pursuing attractive business opportunities that may arise prior to the completion of the merger.

Failure to complete the merger could negatively impact the stock price and future business and financial results of SI Financial.

SI Financial has already incurred substantial expenses in connection with the merger. If the merger is not completed, the ongoing business of SI Financial may be adversely affected and SI Financial will be subject to several risks and consequences, including the following:

•

If the merger agreement is terminated under specified circumstances, SI Financial will be required to pay a termination fee of  $7.4 million;

​

•

SI Financial will be required to pay certain costs relating to the merger, whether or not the merger is completed, such as legal, accounting, financial advisory and printing fees;

​

•

under the merger agreement, SI Financial is subject to certain restrictions on the conduct of its business prior to completing the merger, which may adversely affect its operating results;

​

•

matters relating to the merger may require substantial commitments of time and resources by SI Financial management, which could otherwise have been devoted to other opportunities that may have been beneficial to SI Financial as an independent company;

​

•

SI Financial may experience negative reactions from the financial markets and from its customers and employees; and

​

•

SI Financial could be subject to litigation related to any failure to complete the merger or to enforcement proceedings to perform its obligations under the merger agreement.

​

The termination fee and the restrictions on solicitation contained in the merger agreement may discourage other companies from trying to acquire SI Financial.

Until the completion of the merger, with some exceptions, SI Financial is prohibited from soliciting, initiating, encouraging or participating in any discussion of or otherwise considering any inquiry or proposal that may lead to an acquisition proposal, such as a merger or other business combination transactions, with any person other than Berkshire Hills Bancorp. In addition, SI Financial has agreed to pay a $7.4 million termination fee to Berkshire Hills Bancorp in specified circumstances. These provisions could discourage other companies that may have an interest in acquiring SI Financial from considering or proposing such an acquisition even though those other companies might be willing to offer greater value to SI Financial’s stockholders than Berkshire Hills Bancorp has offered in the merger. The payment of the termination fee could also have a material adverse effect on SI Financial’s financial condition.

Certain of SI Financial’s officers and directors have interests that are different from, or in addition to, interests of SI Financial stockholders generally.

Directors and officers of SI Financial have interests in the merger that are different from, or in addition to, the interests of SI Financial stockholders generally. The SI Financial board of directors was aware of these interests and considered them, among other matters, in approving the merger agreement and the transactions contemplated by the merger agreement and in determining to recommend to the SI Financial stockholders that they vote to approve the merger proposal. These interests are described in detail under the section entitled “The Merger — Interests of SI Financial’s Directors and Executive Officers in the Merger that are Different From Yours” beginning on page 64.

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SI Financial stockholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management of the combined organization.

SI Financial stockholders currently have the right to vote in the election of the SI Financial board of directors and on various other matters affecting SI Financial. Upon the completion of the merger, each SI Financial stockholder will become a stockholder of Berkshire Hills Bancorp with a percentage ownership of the combined organization that is significantly smaller than the stockholder’s percentage ownership of SI Financial. It is expected that the former stockholders of SI Financial as a group will receive shares in the merger constituting approximately 11.5% of the outstanding shares of Berkshire Hills Bancorp common stock immediately after the merger, representing less than a majority of the ownership and voting power of Berkshire Hills Bancorp. As a result, SI Financial stockholders will have significantly less influence on the management and policies of Berkshire Hills Bancorp than they now have on the management and policies of SI Financial.

The shares of Berkshire Hills Bancorp common stock to be received by SI Financial stockholders receiving the stock consideration as a result of the merger will have different rights from shares of SI Financial common stock.

Following completion of the merger, SI Financial stockholders will no longer be stockholders of SI Financial but will instead be stockholders of Berkshire Hills Bancorp. There will be important differences between the current rights of SI Financial stockholders and the rights of Berkshire Hills Bancorp stockholders that may be important to SI Financial stockholders. See “Comparison of Rights of Stockholders” beginning on page 87 for a discussion of the material differences between the rights associated with Berkshire Hills Bancorp common stock and SI Financial common stock.

The fairness opinion received by SI Financial’s board of directors from SI Financial’s financial advisor prior to execution of the merger agreement does not reflect changes in circumstances subsequent to the date of the fairness opinion.

KBW, SI Financial’s financial advisor in connection with the merger, delivered to the board of directors of SI Financial its opinion dated December 11, 2018. The opinion does not speak as of the time the merger will be completed or any date other than the date of such opinion. The opinion does not reflect changes that may occur or may have occurred after the date of the opinion, including changes to the operations and prospects of Berkshire Hills Bancorp or SI Financial, changes in general market and economic conditions or regulatory or other factors. Any such changes may materially alter or affect the relative values of Berkshire Hills Bancorp and SI Financial.

There is no assurance when or even if the merger will be completed.

Completion of the merger is subject to satisfaction or waiver of a number of conditions. See “The Merger — Conditions to Completing the Merger” on page 72. There can be no assurance that Berkshire Hills Bancorp and SI Financial will be able to satisfy the closing conditions or that closing conditions beyond their control will be satisfied or waived.

Berkshire Hills Bancorp and SI Financial can agree at any time to terminate the merger agreement, even if SI Financial stockholders have already voted to approve the merger agreement. Berkshire Hills Bancorp and SI Financial can also terminate the merger agreement under other specified circumstances. See “The Merger — Terminating the Merger Agreement” on page 82.

Regulatory approvals may not be received, may take longer than expected or impose conditions that are not presently anticipated.

Before the merger may be completed, certain approvals or consents must be obtained from the various bank regulatory and other authorities in the United States, the Commonwealth of Massachusetts and the States of Connecticut and Rhode Island. There can be no assurance as to whether the federal or state regulatory approval will be received or the timing of the approvals. Berkshire Hills Bancorp is not obligated to complete the merger if the regulatory approvals received in connection with the completion of the merger include any conditions or restrictions that would constitute a “burdensome condition” as defined in the

16

merger agreement. While SI Financial does not currently expect that any such conditions or restrictions would be imposed, there can be no assurance that they will not be, and such conditions or restrictions could have the effect of delaying or preventing completion of the merger.

Goodwill incurred in the merger may negatively affect Berkshire Hills Bancorp’s financial condition.

To the extent that the merger consideration, consisting of the number of shares of Berkshire Hills Bancorp common stock issued or to be issued in the merger, exceeds the fair value of the net assets, including identifiable intangibles of SI Financial, that amount will be reported as goodwill by Berkshire Hills Bancorp. In accordance with current accounting guidance, goodwill will not be amortized but will be evaluated for impairment annually. A failure to realize expected benefits of the merger could adversely impact the carrying value of the goodwill recognized in the merger, and in turn negatively affect Berkshire Hills Bancorp’s financial condition.

SI Financial stockholders do not have dissenters’ or appraisal rights in the merger.

Appraisal or dissenters’ rights are statutory rights that, if applicable under law, enable stockholders to dissent from an extraordinary transaction, such as a merger, and to demand that the corporation pay the fair value for their shares as determined by a court in a judicial proceeding instead of receiving the consideration offered to stockholders in that extraordinary transaction. Under Maryland law, and pursuant to SI Financial’s articles of incorporation, holders of SI Financial common stock are not entitled to appraisal rights in the merger with respect to their shares of SI Financial common stock because SI Financial common stock is listed on a national securities exchange and SI Financial’s articles of incorporation do not provide for appraisal rights unless specifically granted by SI Financial’s board of directors.

Berkshire Hills Bancorp may be unable to successfully integrate SI Financial’s operations or otherwise realize the expected benefits from the merger, which would adversely affect Berkshire Hills Bancorp’s results of operations and financial condition.

The merger involves the integration of two companies that have previously operated independently. The difficulties of combining the operations of the two companies include:

•

integrating personnel with diverse business backgrounds;

​

•

combining different corporate cultures; and

​

•

retaining key employees.

​

The process of integrating operations could cause an interruption of, or loss of momentum in, the activities of the business and the loss of key personnel. The integration of the two companies will require the experience and expertise of certain key employees of SI Financial who are expected to be retained by Berkshire Hills Bancorp. Berkshire Hills Bancorp may not be successful in retaining these employees for the time period necessary to successfully integrate SI Financial’s operations with those of Berkshire Hills Bancorp. The diversion of management’s attention and any delay or difficulty encountered in connection with the merger and the integration of the two companies’ operations could have an adverse effect on the business and results of operation of Berkshire Hills Bancorp following the merger.

The success of the merger will depend, in part, on Berkshire Hills Bancorp’s ability to realize the anticipated benefits and cost savings from combining the business of Berkshire Hills Bancorp with SI Financial. If Berkshire Hills Bancorp is unable to successfully integrate SI Financial, the anticipated benefits and cost savings of the merger may not be realized fully or may take longer to realize than expected. For example, Berkshire Hills Bancorp may fail to realize the anticipated increase in earning and cost savings anticipated to be derived from the acquisition. In addition, as with regard to any merger, a significant decline in asset valuations or cash flows may also cause Berkshire Hills Bancorp not to realize expected benefits.

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The price of Berkshire Hills Bancorp common stock might decrease after the merger.

Upon completion of the merger, holders of SI Financial common stock will become holders of Berkshire Hills Bancorp common stock. Berkshire Hills Bancorp common stock could decline in value after the merger. The market value of Berkshire Hills Bancorp common stock fluctuates based upon various factors, including changes in the business, operations or prospects of Berkshire Hills Bancorp, market assessments of the merger, regulatory considerations, market and economic considerations, and other factors. Further, the market price of Berkshire Hills Bancorp common stock after the merger may be affected by factors different from those currently affecting the common stock of Berkshire Hills Bancorp or SI Financial. The businesses of SI Financial and Berkshire Hills Bancorp differ and, accordingly, the results of operations of the combined company and the market price of the combined company’s shares of common stock may be affected by factors different from those currently affecting the independent results of operations and market prices of common stock of each of SI Financial and Berkshire Hills Bancorp. For a discussion of the businesses of SI Financial and Berkshire Hills Bancorp and of certain factors to consider in connection with those businesses, see the documents incorporated by reference in this proxy statement/​prospectus and referred to under “Where You Can Find More Information” beginning on page 96.

Litigation relating to the merger could result in significant costs, management distraction, and/or a delay of or injunction against the merger.

On February 8, 2019, one purported SI Financial stockholder filed a putative class action lawsuit against SI Financial, Berkshire Hills Bancorp and the members of the SI Financial board of directors in the United States District Court for the District of Connecticut, captioned Karp v. SI Financial Group, Inc. et al., Docket No. 3:19-cv-00199. The plaintiff, on behalf of himself and similarly-situated SI Financial stockholders, generally alleges that the registration statement filed with the SEC on February 4, 2019 contains materially misleading omissions or misrepresentations in violation of Section 14(a) and Section 20(a) of the Exchange Act, and Rule 14a-9 promulgated thereunder. The plaintiff seeks injunctive relief, unspecified damages, and an award of attorneys’ fees and expenses.

On February 15, 2019, one purported SI Financial stockholder filed a lawsuit against SI Financial and the members of the SI Financial board of directors in the United States District Court for the District of Connecticut, captioned McHugh v. SI Financial Group, Inc. et al., Docket No. 3:19-cv-00236. The plaintiff generally alleges that the registration statement filed with the SEC on February 4, 2018 contains materially misleading omissions or misrepresentations in violation of Section 14(a) and Section 20(a) of the Exchange Act, and Rule 14a-9 promulgated thereunder. The plaintiff seeks injunctive relief, unspecified damages, and an award of attorneys’ fees and expenses.

The outcomes of these actions are uncertain and could result in significant costs to SI Financial and/or Berkshire Hills Bancorp, including costs associated with the indemnification of SI Financial’s directors and officers. Other plaintiffs may also file lawsuits against SI Financial, Berkshire Hills Bancorp and/or their directors and officers in connection with the merger. The defense or settlement of any lawsuits or claims relating to the merger may have a material adverse effect on the business, financial condition and results of operations of SI Financial, Berkshire Hills Bancorp and/or the combined company.

If the actions remain unresolved, they could prevent or delay the completion of the merger. One of the conditions to the consummation of the merger is the absence of any order, decree or injunction of a court or agency enjoining or prohibiting the consummation of the merger or the bank merger or of any proceeding instituted by a governmental entity for the purpose of enjoining the merger, the bank merger or the transactions contemplated by the merger agreement. Consequently, if a settlement or other resolution is not reached in this or any other lawsuits that are filed or in any regulatory proceeding, or this plaintiff or any other claimants secure injunctive or other relief or a regulatory authority issues an order or other directive prohibiting, restricting or making illegal the consummation of the merger, the bank merger or the transactions contemplated by the merger agreement, then such injunctive or other relief may prevent the merger from becoming effective in a timely manner or at all.

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Risks Relating to Berkshire Hills Bancorp’s Business.

You should read and consider risk factors specific to Berkshire Hills Bancorp’s business that will also affect the combined company after the merger. These risks are described in the sections entitled “Risk Factors” in Berkshire Hills Bancorp’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and in other documents incorporated by reference into this document. Please see the section entitled “Where You Can Find More Information” for the location of information incorporated by reference into this document.

Risks Relating to SI Financial’s Business.

You should read and consider risk factors specific to SI Financial’s business that will also affect the combined company after the merger. These risks are described in the sections entitled “Risk Factors” in SI Financial’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 and in other documents incorporated by reference into this document. Please see the section entitled “Where You Can Find More Information” for the location of information incorporated by reference into this document.

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CAUTIONARY STATEMENT ABOUT FORWARD-LOOKING STATEMENTS

Some of the statements contained or incorporated by reference in this document are forward looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 giving Berkshire Hills Bancorp’s or SI Financial’s expectations or predictions of future financial or business performance or conditions. Forward-looking statements are typically identified by words such as “believe,” “expect,” “anticipate,” “intend,” “target,” “estimate,” “continue,” “positions,” “projections,” “prospects” or “potential,” by future conditional verbs such as “will,” “would,” “should,” “could” or “may,” or by variations of such words or by similar expressions. Such forward-looking statements include, but are not limited to, statements about the benefits of the merger or the bank merger, including future financial and operating results of Berkshire Hills Bancorp, SI Financial or the combined company following the merger, the combined company’s plans, objectives, expectations and intentions, the expected timing of the completion of the merger, financing plans and the availability of capital, the likelihood of success and impact of litigation and other statements that are not historical facts. These statements are only predictions based on Berkshire Hills Bancorp’s and SI Financial’s current expectations and projections about future events. There are important factors that could cause Berkshire Hills Bancorp’s and SI Financial’s actual results, level of activity, performance or achievements to differ materially from the results, level of activity, performance or achievements expressed or implied by the forward-looking statements. In particular, you should consider the numerous risks and uncertainties described in the section entitled “Risk Factors” beginning on page 14.

These forward-looking statements are subject to numerous assumptions, risks, and uncertainties which change over time. In addition to factors previously disclosed in Berkshire Hills Bancorp’s and SI Financial’s reports filed with the SEC, the following factors, among others, could cause actual results to differ materially from forward-looking statements:

•

the inability to close the merger and the bank merger in a timely manner;

​

•

the failure to complete the merger due to the failure of SI Financial stockholders to approve the merger proposal;

​

•

failure to obtain applicable regulatory approvals and meet other closing conditions to the merger on the expected terms and schedule;

​

•

the potential impact of announcement or consummation of the merger on relationships with third parties, including customers, employees, and competitors;

​

•

business disruption following the merger;

​

•

difficulties and delays in integrating the Berkshire Hills Bancorp and SI Financial businesses or fully realizing cost savings and other benefits;

​

•

Berkshire Hills Bancorp’s potential exposure to unknown or contingent liabilities of SI Financial;

​

•

the challenges of integrating, retaining, and hiring key personnel;

​

•

failure to attract new customers and retain existing customers in the manner anticipated;

​

•

the outcome of pending or threatened litigation, or of matters before regulatory agencies, whether currently existing or commencing in the future, including litigation related to the merger;

​

•

any interruption or breach of security resulting in failures or disruptions in customer account management, general ledger, deposit, loan, or other systems;

​

•

changes in Berkshire Hills Bancorp’s stock price before closing, including as a result of the financial performances of Berkshire Hills Bancorp and SI Financial prior to closing;

​

•

operational issues stemming from, and/or capital spending necessitated by, the potential need to adapt to industry changes in information technology systems, on which Berkshire Hills Bancorp and SI Financial are highly dependent;

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20

•

changes in legislation, regulation, policies, or administrative practices, whether by judicial, governmental, or legislative action, including, but not limited to, the Dodd-Frank Wall Street Reform and Consumer Protection Act, which we refer to as the “Dodd-Frank Act,” and other changes pertaining to banking, securities, taxation, rent regulation and housing, financial accounting and reporting, environmental protection, and insurance, and the ability to comply with such changes in a timely manner;

​

•

changes in the monetary and fiscal policies of the U.S. Government, including policies of the U.S. Department of the Treasury and the Federal Reserve;

​

•

changes in interest rates, which may affect Berkshire Hills Bancorp’s or SI Financial’s net income, prepayment penalty income, mortgage banking income, and other future cash flows, or the market value of Berkshire Hills Bancorp’s or SI Financial’s assets, including its investment securities;

​

•

potential changes to the federal tax code;

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•

changes in accounting principles, policies, practices, or guidelines;

​

•

changes in Berkshire Hills Bancorp’s credit ratings or in Berkshire Hills Bancorp’s ability to access the capital markets;

​

•

natural disasters, war, or terrorist activities; and

​

•

other economic, competitive, governmental, regulatory, technological, and geopolitical factors affecting Berkshire Hills Bancorp’s or SI Financial’s operations, pricing, and services.

​

Additionally, the timing and occurrence or non-occurrence of events may be subject to circumstances beyond Berkshire Hills Bancorp’s or SI Financial’s control.

Annualized, pro forma, projected and estimated numbers are used for illustrative purposes only, are not forecasts and may not reflect actual results.

For any forward-looking statements made in this document or in any documents incorporated by reference into this document, Berkshire Hills Bancorp and SI Financial claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. You are cautioned not to place undue reliance on these statements, which speak only as of the date of this document or the date of the applicable document incorporated by reference in this document. Except to the extent required by applicable law, Berkshire Hills Bancorp and SI Financial do not undertake to update forward-looking statements to reflect facts, circumstances, assumptions, or events that occur after the date the forward-looking statements are made. All written and oral forward-looking statements concerning the merger or other matters addressed in this document and attributable to Berkshire Hills Bancorp, SI Financial, or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this document.

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SELECTED HISTORICAL FINANCIAL INFORMATION

The following tables show summarized historical financial data for Berkshire Hills Bancorp and SI Financial. You should read this summary financial information in connection with Berkshire Hills Bancorp’s historical financial information, which is incorporated by reference into this document, and in connection with SI Financial’s historical financial information, which is incorporated by reference into this document. See the section entitled “Where You Can Find More Information” for instructions on how to obtain the information that has been incorporated by reference. Amounts as of and for the nine months ended September 30, 2018 and 2017 are unaudited and are not necessarily indicative of the results of operations for the fully year or any other interim period. Management of Berkshire Hills Bancorp and SI Financial believe that such amounts reflect all adjustments (consisting only of normal recurring adjustments) necessary for a fair presentation of its respective results of operations and financial position as of the dates and for the periods indicated.

SELECTED HISTORICAL FINANCIAL AND OTHER DATA
OF BERKSHIRE HILLS BANCORP, INC.

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(1)

Adjusted measurements are non-GAAP financial measures that are adjusted to exclude certain revenue and expense items primarily related to acquisitions and restructuring activities. Refer to the Berkshire Hills Bancorp Reconciliation of Non-GAAP Financial Measures and discussion of Non-GAAP financial measures for additional information.

​

(2)

Non-GAAP financial measure.

​

(3)

All performance ratios are annualized and are based on average balance sheet amounts, where applicable.

​

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(4)

Fully taxable equivalent considers the impact of tax advantaged investment securities and loans.

​

(5)

Generally accepted accounting principles require that loans acquired in a business combination be recorded at fair value, whereas loans from business activities are recorded at cost. The fair value of loans acquired in a business combination includes expected loan losses, and there is no loan loss allowance recorded for these loans at the time of acquisition. Accordingly, the ratio of the loan loss allowance to total loans is reduced as a result of the existence of such loans, and this measure is not directly comparable to prior periods. Similarly, net loan charge-offs are normally reduced for loans acquired in a business combination since these loans are recorded net of expected loan losses. Therefore, the ratio of net loan charge-offs to average loans is reduced as a result of the existence of such loans, and this measure is not directly comparable to prior periods. Other institutions may have loans acquired in a business combination, and therefore there may be no direct comparability of these ratios between and among other institutions.

​

24

BERKSHIRE HILLS BANCORP NON-GAAP FINANCIAL MEASURES

This document contains certain non-GAAP financial measures in addition to results presented in accordance with Generally Accepted Accounting Principles (“GAAP”). These non-GAAP measures are intended to provide the reader with additional supplemental perspectives on operating results, performance trends, and financial condition. Non-GAAP financial measures are not a substitute for GAAP measures; they should be read and used in conjunction with Berkshire Hills Bancorp’s GAAP financial information. A reconciliation of non-GAAP financial measures to GAAP measures is provided below. In all cases, it should be understood that non-GAAP measures do not depict amounts that accrue directly to the benefit of shareholders. An item which management excludes when computing non-GAAP adjusted earnings can be of substantial importance to Berkshire Hills Bancorp’s results for any particular quarter or year. Berkshire Hills Bancorp’s non-GAAP adjusted earnings information set forth is not necessarily comparable to non-GAAP information which may be presented by other companies. Each non-GAAP measure used by Berkshire Hills Bancorp in this report as supplemental financial data should be considered in conjunction with Berkshire Hills Bancorp’s GAAP financial information.

Berkshire Hills Bancorp utilizes the non-GAAP measure of adjusted earnings in evaluating operating trends, including components for adjusted revenue and expense. These measures exclude amounts which Berkshire Hills Bancorp views as unrelated to its normalized operations, including securities gains/losses, gains on the sale of business operations and assets, losses recorded for hedge terminations, merger costs, restructuring costs, legal settlements, and systems conversion and contract restructuring costs. Securities gains/losses include gains/losses on equity securities beginning in the first quarter of 2018. In 2017, there was a large adjustment for the write-down of the deferred tax asset at year-end due to the passage of federal tax reform. There was also an adjustment for investments in employees and communities which were made by Berkshire Hills Bancorp in recognition of the future benefits of federal tax reform. Berkshire Hills Bancorp also measures adjusted revenues and adjusted expenses which result from the above adjustments. An adjustment is also calculated to adjust for the difference between tax expense calculated for adjusted earnings and for GAAP earnings.

Berkshire Hills Bancorp calculates certain profitability measures based on its adjusted revenue, expenses, and earnings. Berkshire Hills Bancorp also calculates adjusted earnings per share based on its measure of adjusted earnings and based on diluted common shares. Berkshire Hills Bancorp views these amounts as important to understanding its operating trends, particularly due to the impact of accounting standards related to merger and acquisition activity. Analysts also rely on these measures in estimating and evaluating Berkshire Hills Bancorp’s performance. Management also believes that the computation of non-GAAP adjusted earnings and adjusted earnings per share may facilitate the comparison of Berkshire Hills Bancorp to other companies in the financial services industry.

Charges related to merger and acquisition activity consist primarily of severance/benefit related expenses, contract termination costs, system conversion costs, variable compensation expenses, and professional fees. Systems conversion costs relate primarily to Berkshire Hills Bancorp’s core systems conversion and related systems conversions costs, and core systems contract restructuring. Restructuring costs primarily consist of Berkshire Hills Bancorp’s continued effort to create efficiencies in operations through calculated adjustments to the branch banking footprint. Expense adjustments include variable rate compensation related to non-operating items.

Berkshire Hills Bancorp also adjusts certain equity related measures to exclude intangible assets due to the importance of these measures to the investment community.

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BERKSHIRE HILLS BANCORP RECONCILIATION OF NON-GAAP FINANCIAL MEASURES

(1)

Ratios are annualized and based on average balance sheet amounts, where applicable. Quarterly data may not sum to year-to-date data due to rounding.

​

(2)

Non-GAAP financial measure.

​

26

SELECTED HISTORICAL FINANCIAL AND OTHER DATA OF SI FINANCIAL