FORM OF SAVINGS INSTITUTE BANK AND TRUST COMPANY CHANGE IN CONTROL AGREEMENT

Exhibit 10.5

FORM OF

SAVINGS INSTITUTE BANK AND TRUST COMPANY

CHANGE IN CONTROL AGREEMENT

This AGREEMENT (“Agreement”) is hereby entered into as of                     , 2004, by and between Savings Institute Bank and Trust Company (the “Bank”), a federally-chartered savings bank with its principal offices at 803 Main Street, Willimantic, Connecticut 06226,                      (“Executive”) and SI Financial Group, Inc. (the “Company”), a federally-chartered corporation and the holding company of the Bank, as guarantor.

WHEREAS, the Bank recognizes the importance of Executive to the Bank’s operations and wishes to protect his position with the Bank in the event of a change in control of the Bank or the Company for the period provided for in this Agreement; and

WHEREAS, Executive and the Board of Directors of the Bank desire to enter into an agreement setting forth the terms and conditions of payments due to Executive in the event of a change in control and the related rights and obligations of each of the parties.

NOW, THEREFORE, in consideration of the promises and mutual covenants herein contained, it is hereby agreed as follows:

(a) The term of this Agreement shall be (i) the initial term, consisting of the period commencing on the date of this Agreement (the “Effective Date”) and ending on the                     anniversary of the Effective Date, plus (ii) any and all extensions of the initial term made pursuant to this Section 1.

(b) Commencing on the first anniversary of the Effective Date and continuing each anniversary date thereafter, the Board of Directors of the Bank (the “Board of Directors”) may extend the term of this Agreement for an additional one (1) year period beyond the then effective expiration date, provided that Executive shall not have given at least sixty (60) days’ written notice of his desire that the term not be extended.

(c) Notwithstanding anything in this Section to the contrary, this Agreement shall terminate if Executive or the Bank terminates Executive’s employment prior to a Change in Control.

(a) Upon the occurrence of a Change in Control of the Bank or the Company followed at any time during the term of this Agreement by the termination of Executive’s employment in accordance with the terms of this Agreement, other than for Just Cause, as defined in Section 2(c) of this Agreement, the provisions of Section 3 of this Agreement

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shall apply. Upon the occurrence of a Change in Control, Executive shall have the right to elect to voluntarily terminate his employment at any time during the term of this Agreement following an event constituting “Good Reason.”

“Good Reason” means, unless Executive has consented in writing thereto, the occurrence following a Change in Control, of any of the following:

(b) For purposes of this Agreement, a “Change in Control” shall be deemed to occur on the earliest of any of the following events:

(i) Merger: The Company merges into or consolidates with another corporation, or merges another corporation into the Company, and as a result less than a majority of the combined voting power of the resulting corporation immediately after the merger or consolidation is held by persons who were stockholders of the Company immediately before the merger or consolidation.

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(ii) Acquisition of Significant Share Ownership: The Company files, or is required to file, a report on Schedule 13D or another form or schedule (other than Schedule 13G) required under Sections 13(d) or 14(d) of the Securities Exchange Act of 1934, if the schedule discloses that the filing person or persons acting in concert has or have become the beneficial owner of 25% or more of a class of the Company’s voting securities, but this clause (b) shall not apply to beneficial ownership of Company voting shares held in a fiduciary capacity by an entity of which the Company directly or indirectly beneficially owns 50% or more of its outstanding voting securities.

(iii) Change in Board Composition: During any period of two consecutive years, individuals who constitute the Company’s Board of Directors at the beginning of the two-year period cease for any reason to constitute at least a majority of the Company’s Board of Directors; provided, however, that for purposes of this clause (iii), each director who is first elected by the board (or first nominated by the board for election by the stockholders) by a vote of at least two-thirds (2/3) of the directors who were directors at the beginning of the two-year period shall be deemed to have also been a director at the beginning of such period; or

(iv) Sale of Assets: The Company sells to a third party all or substantially all of its assets.

Notwithstanding anything in this Agreement to the contrary, in no event shall the conversion of SI Bancorp, MHC from mutual to stock form (including without limitation, through the formation of a stock holding company) constitute a “Change in Control” for purposes of this Agreement.

(c) Executive shall not have the right to receive termination benefits pursuant to Section 3 hereof upon termination for Just Cause. The term “Just Cause” shall mean termination because of Executive’s personal dishonesty, incompetence, willful misconduct, any breach of fiduciary duty involving personal profit, intentional failure to perform stated duties, willful violation of any law, rule, regulation (other than traffic violations or similar offenses), final cease and desist order, or any material breach of any provision of this Agreement. Notwithstanding the foregoing, Executive shall not be deemed to have been terminated for Just Cause unless and until there shall have been delivered to him a copy of a resolution duly adopted by the affirmative vote of a majority of the entire membership of the Board of Directors at a meeting of the Board of Directors called and held for that purpose (after reasonable notice to Executive and an opportunity for him, together with counsel, to be heard before the Board of Directors), finding that in the good faith opinion of the Board of Directors, Executive was guilty of conduct justifying termination for Just Cause and specifying the particulars thereof in detail. Executive shall not have the right to receive compensation or other benefits for any period after termination for Just Cause. During the period beginning on the date of the Notice of Termination for Just Cause pursuant to Section 4 hereof through the Date of Termination, stock options granted to Executive under any stock option plan shall not be exercisable nor shall any unvested stock awards granted to Executive under any stock benefit plan of the Bank, the Company or any

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subsidiary or affiliate thereof, vest. At the Date of Termination, such stock options and any such unvested stock awards shall become null and void and shall not be exercisable by or delivered to Executive at any time subsequent to such termination for Just Cause.

(a) If Executive’s employment is voluntarily (in accordance with Section 2(a) of this Agreement) or involuntarily terminated within                      years of a Change in Control, Executive shall receive:

(b) Notwithstanding the preceding provisions of this Section 3, in no event shall the aggregate payments or benefits to be made or afforded to Executive under said paragraphs (the “Termination Benefits”) constitute an “excess parachute payment” under Section 280G of the Code or any successor thereto, and to avoid such a result, Termination Benefits will be reduced, if necessary, to an amount (the “Non-Triggering Amount”), the value of which is one dollar ($1.00) less than an amount equal to three (3) times Executive’s “base amount,” as determined in accordance with said Section 280G. The allocation of the reduction required hereby among the Termination Benefits provided by this Section 3 shall be determined by Executive.

(a) Any purported termination by the Bank or by Executive shall be communicated by Notice of Termination to the other party hereto. For purposes of this Agreement, a “Notice of Termination” shall mean a written notice which shall indicate the specific termination provision in this Agreement relied upon and shall set forth in detail the facts and circumstances claimed to provide a basis for termination of Executive’s employment under the provision so indicated.

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(b) “Date of Termination” shall mean the date specified in the Notice of Termination (which, in the case of a termination for Just Cause, shall not be less than thirty (30) days from the date such Notice of Termination is given).

All payments provided in this Agreement shall be timely paid in cash or check from the general funds of the Bank. The Company, however, unconditionally guarantees payment and provision of all amounts and benefits due hereunder to Executive and, if such amounts and benefits due from the Bank are not timely paid or provided by the Bank, such amounts and benefits shall be paid or provided by the Company.

This Agreement contains the entire understanding between the parties hereto and supersedes any prior agreement between the Bank and Executive, except that this Agreement shall not affect or operate to reduce any benefit or compensation inuring to Executive of a kind elsewhere provided. No provision of this Agreement shall be interpreted to mean that Executive is subject to receiving fewer benefits than those available to him without reference to this Agreement. Nothing in this Agreement shall confer upon Executive the right to continue in the employ of the Bank or shall impose on the Bank any obligation to employ or retain Executive in its employ for any period.

(a) Except as required by law, no right to receive payments under this Agreement shall be subject to anticipation, commutation, alienation, sale, assignment, encumbrance, charge, pledge, or hypothecation or to execution, attachment, levy or similar process or assignment by operation of law, and any attempt, voluntary or involuntary, to affect any such action shall be null, void and of no effect.

(b) This Agreement shall be binding upon, and inure to the benefit of, Executive, the Bank and their respective successors and assigns.

(a) This Agreement may not be modified or amended except by an instrument in writing signed by the parties hereto.

(b) No term or condition of this Agreement shall be deemed to have been waived, nor shall there be any estoppel against the enforcement of any provision of this Agreement, except by written instrument of the party charged with such waiver or estoppel. No such written waiver shall be deemed a continuing waiver unless specifically stated therein, and each such waiver shall operate only as to the specific term or condition waived and shall not constitute a waiver of such term or condition for the future or as to any act other than that specifically waived.

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If, for any reason, any provision of this Agreement, or any part of any provision, is held invalid, such invalidity shall not affect any other provision of this Agreement or any part of such provision not held so invalid, and each such other provision and part thereof shall to the full extent consistent with law continue in full force and effect.

The headings of sections and paragraphs herein are included solely for convenience of reference and shall not control the meaning or interpretation of any of the provisions of this Agreement. In addition, references herein to the masculine shall apply to both the masculine and the feminine.

Except to the extent preempted by federal law, the validity, interpretation, performance, and enforcement of this Agreement shall be governed by the laws of the State of Connecticut, without regard to principles of conflicts of law of that State.

Any dispute or controversy arising under or in connection with this Agreement shall be settled exclusively by arbitration, conducted before a panel of three arbitrators sitting in a location selected by Executive within fifty (50) miles from the location of the Bank, in accordance with the rules of the American Arbitration Bank then in effect. Judgment may be entered on the arbitrator’s award in any court having jurisdiction; provided, however, that Executive shall be entitled to seek specific performance of his right to be paid until the Date of Termination during the pendency of any dispute or controversy arising under or in connection with this Agreement.

All reasonable legal fees paid or incurred by Executive pursuant to any dispute or question of interpretation relating to this Agreement shall be paid or reimbursed by the Bank, only if Executive is successful pursuant to a legal judgment, arbitration or settlement.

The Company or the Bank shall provide Executive (including his heirs, executors and administrators) with coverage under a standard directors’ and officers’ liability insurance policy at its expense and shall indemnify Executive (and his heirs, executors and administrators) to the fullest extent permitted under applicable law against all expenses and liabilities reasonably incurred by him in connection with or arising out of any action, suit or proceeding in which he may be involved by reason of his having been a director or officer of the Company or the Bank

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(whether or not he continues to be a director or officer at the time of incurring such expenses or liabilities), such expenses and liabilities to include, but not be limited to, judgments, court costs, attorneys’ fees and the cost of reasonable settlements.

The Bank and the Company shall require any successor or assignee, whether direct or indirect, by purchase, merger, consolidation or otherwise, to all or substantially all of the business or assets of the Bank or the Company, expressly and unconditionally to assume and agree to perform the Bank’s and the Company’s obligations under this Agreement, in the same manner and to the same extent that the Bank and the Company would be required to perform if no such succession or assignment had taken place.

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SIGNATURES

IN WITNESS WHEREOF, Savings Institute Bank and Trust Company and SI Financial Group, Inc. have caused this Agreement to be executed and their seals to be affixed hereunto by their duly authorized officers, and Executive has signed this Agreement, on the              day of                     , 200            .

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