Exhibit 10.4.3
    

    

    

    
      2005 SUPPLEMENTAL RETIREMENT INCOME AGREEMENT
    

    
      BY AND BETWEEN
    

    
      BROOKLINE BANK
    

    
      AND
    

    
      CHARLES H. PECK
    

    
      THIS 2005 SUPPLEMENTAL RETIREMENT INCOME AGREEMENT (the “Agreement”) by
      and between BROOKLINE BANK, a savings bank organized and existing under
      the laws of the Commonwealth of Massachusetts (the “Bank”), and CHARLES
      H. PECK (the “Executive”) is adopted effective as of January 1,
      2005.  This Agreement shall in all respects be subject to the provisions
      set forth herein.  The purpose of this Agreement is to provide certain
      retirement and death benefits to the Executive in addition to those that
      may be available to the Executive under the Bank’s retirement and
      pension plans (the “Current Plans”) and under the Supplemental
      Retirement Income Agreement by and between the Bank and the Executive,
      which was effective as of February 28, 1995 (the “Original Agreement”).  
    

    
      The Original Agreement was frozen as of December 31, 2004 in order to
      avoid the limitations imposed under Section 409A of the Internal Revenue
      Code of 1986, as amended (the “Code”) with respect to the benefits
      accrued thereunder.  This Agreement is intended to comply with the
      requirements of Section 409A of the Code, including the guidance issued
      to date by the Internal Revenue Service (the “IRS”) and the final
      regulations issued by the IRS in April 2007.  No benefits payable under
      this Agreement shall be deemed to be grandfathered for purposes of
      Section 409A of the Code.  This Agreement shall be operated in
      compliance with Section 409A of the Code.  This Agreement is an unfunded
      plan for tax purposes.  The provisions of the Agreement shall be
      construed to effectuate such intentions.
    

    
      Accordingly, the Bank hereby adopts this Agreement pursuant to the terms
      and provisions set forth below and in consideration of the mutual
      covenants hereinafter set forth, the parties hereto agree as follows:
    

    
      1         Definitions.  For
      purposes hereof the following terms shall have the meanings ascribed to
      them below:
    

    
      (a)       “Average Compensation” shall mean the average of the
      Compensation, received by the Executive in the three (3) calendar years
      in the ten (10) calendar-year period prior to the Executive’s Retirement
      which produces the highest rate of Compensation.
    

    
      (b)       “Beneficiary” shall mean that person designated, in the most
      recent writing submitted by Executive to the Bank (the “Beneficiary
      Designation”), as the Beneficiary under this Agreement.  In the event
      that Executive dies without having so named a person surviving him as
      the Beneficiary hereunder, the Beneficiary hereunder shall be the
      Executive’s estate.  In the event the Beneficiary survives the Executive
      but dies before the expiration of the Benefit Period, those persons, if
      any, named as alternate beneficiaries in the Beneficiary Designation
      (the “Alternates”) shall thereafter be deemed to be the Beneficiary
      hereunder, provided however, that if the Alternates are deemed to
      be the Beneficiary hereunder but all of such Alternates die before the
      expiration of the Benefit Period, the Executive’s estate shall be deemed
      to be the Beneficiary hereunder.
    

    
      
        

        

      

      
        
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      (c)       “Benefit Period” shall mean, in the case where the Executive
      Separates from Service prior to death, the period commencing on the date
      the Executive Separates from Service and ending on the later to occur of
      (i) said Executive’s death or (ii) the expiration of 180 months from the
      Executive’s Separation from Service; and, in the case where the
      Executive dies while still employed by the Bank, the period commencing
      on the date of the Executive’s death and ending on the earlier to occur
      of (i) the expiration of 180 months from the Executive’s death and (ii)
      the date upon which Executive would have attained (if he had survived to
      such date) the Life Expectancy Age).
    

    
      (d)       “Board” shall mean the Board of Directors of the Bank.
    

    
      (e)       “Change in Control” shall mean a change in the ownership of
      the Company or the Bank, a change in the effective control of the
      Company or the Bank or a change in the ownership of a substantial
      portion of the assets of the Company or the Bank, in each case as
      provided under Section 409A of the Code and the final regulations
      thereunder.
    

    
      (f)       “Committee” shall mean the Compensation Committee of the Bank,
      or such other Committee of the Bank as the Board, from time to time, may
      designate to oversee and administer the terms of this Agreement.
    

    
      (g)       “Company” shall mean Brookline Bancorp, Inc., the stock
      holding company of the Bank.
    

    
      (h)       “Compensation” shall mean the Executive’s total annual base
      salary and bonus, plus no more than $10,000 worth of all other items
      that may be considered “compensation” for purposes of federal income
      taxes (such as vested restricted stock shares and the “spread” realized
      in connection with exercise of stock options).
    

    
      (i)       “Life Expectancy Age” shall mean the age determined by adding
      to the Executive’s age at death the standard life expectancy based upon
      mortality tables utilized by the Savings Bank Employees Retirement
      Association to calculate pension benefits of a healthy male of the
      Executive’s age at death, determined as of the date of the Executive’s
      death.
    

    
      (j)        “Lump Sum Benefit” shall mean a single lump sum payment in an
      amount equal to the lesser of (i) the actuarial equivalent present value
      of the Normal Retirement Benefit, which shall be determined by assuming
      that the Executive receives his Normal Retirement Benefit over the
      Benefit Period, or (ii) $1,370,469.
    

    
      (k)       “Normal Retirement Benefit” shall mean an annual sum which is
      equal to seventy percent (70%) of Average Compensation reduced by (1)
      any distribution which the Executive, his beneficiaries or his estate
      are entitled to receive from the Savings Bank Employees Retirement
      Association Pension Plan derived from Bank contributions, (2) one-half
      of any Social Security benefits, and (3) the amount of the Normal
      Retirement Benefit payable under the Original Agreement.  If a lump sum
      distribution is paid to the Executive, his beneficiaries or his estate
      by the Savings Bank Employees Retirement Association Pension Plan, the
      Normal Retirement Benefit shall be reduced by an amount equal to a life
      only actuarial equivalent of the lump sum distribution.  All
      calculations of benefits or actuarial equivalents in this Agreement
      shall be made using the mortality tables and interest assumptions
      utilized by the Savings Bank Employees Retirement Association Pension
      Plan to calculate benefits and actuarial equivalents.
    

    
      
        

        

      

      
        
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      (l)       “Separation from Service” or “Separates from Service” shall
      mean a termination of the Executive’s services (whether as an employee
      or as an independent contractor) to the Bank for any reason other than
      death.  Whether a Separation from Service has occurred shall be
      determined in accordance with the requirements of Section 409A of the
      Code based on whether the facts and circumstances indicate that the Bank
      and the Executive reasonably anticipated that no further services would
      be performed after a certain date or that the level of bona fide
      services the Executive would perform after such date (whether as an
      employee or as an independent contractor) would permanently decrease to
      no more than twenty percent (20%) of the average level of bona fide
      services performed (whether as an employee or an independent contractor)
      over the immediately preceding thirty-six (36) month period.
    

    
      2         Employment.  The
      Executive agrees to continue to serve the Bank, devoting his normal
      working time to the interests and activities of the Bank, in the
      capacity of President or such other executive capacity as the Board from
      time to time may assign him.
    

    
      3         Salary, Etc.  Payments
      hereunder shall be supplemental and in addition to all other payments of
      salary, pension amounts or profit sharing payments made by the Bank to
      or for the benefit of the Executive.
    

    
      4         Supplemental
      Income Upon Retirement.  Pursuant to Sections 5 and 6 of this
      Agreement, in lieu of payment to the Executive of the Normal Retirement
      Benefit over the Benefit Period, in the event of a Payment Event, as
      defined in Section 5, the Executive shall be entitled to a Lump Sum
      Benefit, payable in accordance with Section 6.
    

    
      5         Payment Events.  The
      Executive shall be entitled to payment of the Lump Sum Benefit as of the
      earliest to occur of the following events (the “Payment Event”):
    

    
      (a)      Separation from Service,
    

    
      (b)      Death, or
    

    
      (c)      Change in Control.
    

    
      6         Timing of
      Payment Event.  The Bank shall pay the Lump Sum Benefit to the
      Executive (or to the Beneficiary if the Executive is not then living)
      within ten (10) business days after the occurrence of a Payment
      Event.  Notwithstanding anything in the Agreement to the contrary, if a
      payment is to be made on account of a Separation from Service to an
      Executive who was a Specified Employee (as defined in Treasury
      Regulation §1.409A-1(i)) as of the date of the Separation from Service,
      then any payment will be made or will commence on the first day of the
      month following the lapse of six (6) months after the date of the
      Separation from Service.
    

    
      7         Benefits
      Unsecured.  All Benefits hereunder shall be paid from the general
      funds of the Bank and no special or separate fund shall necessarily be
      established and no other segregation of assets shall necessarily be made
      to assure the payment of the benefits hereunder.  Neither the Executive
      nor any Beneficiary nor their estates shall have any right title or
      interest whatever in or to any investments, including any insurance
      policy which the Employer may take out to aid it in meeting its
      obligations hereunder.  To the extent that the Executive or any
      Beneficiary acquires the right to receive benefits hereunder such rights
      shall be no greater than the right of an unsecured creditor of the
      Bank.  Notwithstanding the foregoing, nothing herein contained shall
      preclude the Bank from contributing to or making benefit payments from a
      Rabbi Trust.
    

    
      
        

        

      

      
        
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      8         Termination.
    

    
      (a)       Notwithstanding any provisions hereof to the contrary, this
      Agreement shall terminate and be of no further force or effect in the
      event that (i) the Executive is discharged by the Bank for Cause, or
      (ii) the Executive breaches any of the covenants contained in Section 9
      hereof (said termination to be effective even in the event that a court
      should find any of the provisions of said Section 9 to be unenforceable;
      it being the intention of the parties that this Agreement shall
      terminate if the Executive breaches any of the original terms of Section
      9 without regard to any judicial modification pursuant to Section 9(b)
      hereof).
    

    
      (b)       For purposes of this Agreement, a discharge shall be for Cause
      if the Committee shall determine (upon the unanimous vote of the entire
      Committee) that any one or more of the following has occurred:
    

    
      (i)       The Executive shall have committed fraud, embezzlement,
      misappropriation or breach of fiduciary duty against the Bank or against
      any customer or depositor thereof, or shall have committed any such
      action against any other person or entity and such action materially and
      adversely reflects upon the business affairs or reputation of the Bank
      or upon the Executive’s ability to perform his duties hereunder; or
    

    
      (ii)      The Executive shall have been convicted by a court of
      competent jurisdiction of, or pleaded guilty or nolo contendere to, any
      crime involving moral turpitude;
    

    
      (iii)     The Executive shall have (A) materially failed to perform or
      neglected his duties as President of the Bank on a regular basis or (B)
      refused to carry out the duties assigned to him by the Board in
      accordance with Section 2 hereof.
    

    
      (c)       Under no circumstances may the Agreement permit the
      acceleration of the time or form of any payment under the Agreement
      prior to the payment events specified herein, except as provided in this
      Section 8(c).  The Bank may, in its discretion, elect to terminate the
      Agreement in any of the following three circumstances and accelerate the
      payment of the entire unpaid balance of the Executive’s accrued benefits
      as of the date of such payment in accordance with Section 409A of the
      Code:
    

    
      (i)                the Agreement is irrevocably terminated within the 30
      days preceding a Change in Control and (1) all arrangements sponsored by
      the Bank that would be aggregated with the Agreement under Treasury
      Regulation §1.409A-1(c)(2) are terminated, and (2) the Executive and all
      participants under the other aggregated arrangements receive all of
      their benefits under the terminated arrangements within 12 months of the
      date the Bank irrevocably takes all necessary action to terminate the
      Agreement and the other aggregated arrangements;
    

    
      (ii)               the Agreement is irrevocably terminated at a time
      that is not proximate to a downturn in the financial health of the Bank
      and (1) all arrangements sponsored by the Bank that would be aggregated
      with the Agreement under Treasury Regulation 1.409A-1(c) if a Executive
      participated in such arrangements are terminated, (2) no payments are
      made within 12 months of the date the Bank takes all necessary action to
      irrevocably terminate the arrangements, other than payments that would
      be payable under the terms of the arrangements if the termination had
      not occurred, (3) all payments are made within 24 months of the date the
      Bank takes all necessary action to irrevocably terminate the
      arrangements, and (4) the Bank does not adopt a new arrangement that
      would be aggregated with the Agreement under Treasury Regulation
      1.409A-1(c) if a Executive participated in both arrangements, at any
      time within three years following the date the Bank takes all necessary
      action to irrevocably terminate the Agreement; or
    

    
      
        

        

      

      
        
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      (iii)              the Agreement is terminated within 12 months of a
      corporate dissolution taxed under Section 331 of the Code, or with the
      approval of a bankruptcy court pursuant to 11 U.S.C. §503(b)(1)(A),
      provided that the amounts deferred by each Executive under the Agreement
      are included in the Executive’s gross income in the later of (1) the
      calendar year in which the termination of the Agreement occurs, or (2)
      the first calendar year in which the payment is administratively
      practicable.
    

    
      9         Non-Competition,
      Etc.
    

    
      (a)       The Executive hereby agrees that he for a period of five (5)
      years from the date of Separation from Service will not directly or
      indirectly:
    

    
      (i)                        as an individual proprietor, partner,
      stockholder, officer, employee, director, joint venturer, investor,
      lender, or in any other capacity whatsoever (other than as the holder of
      not more than one percent (1%) of the total outstanding stock of a
      publicly held company), anywhere in or within 75 miles of Brookline,
      Massachusetts, engage in the banking business;
    

    
      (ii)                       recruit, solicit or induce, or attempt to
      induce, any employee or employees of the Bank to terminate their
      employment with, or otherwise cease their relationship with, the Bank; or
    

    
      (iii)                      solicit, divert or take away, or attempt to
      divert or to take away, the business or patronage of any of the
      depositors, borrowers, or customers of the Bank.
    

    
      (b)       If any restriction set forth in Section 9(a) is found by any
      court of competent jurisdiction to be unenforceable because it extends
      for too long a period of time or over too great a range of activities or
      in too broad a geographic area, it shall be interpreted to extend only
      over the maximum period of time; range of activities or geographic area
      as to which it may be enforceable.
    

    
      (c)       The restrictions contained in this Section 9 are necessary for
      the protection of the business and goodwill of the Bank and are
      considered by the Executive to be reasonable for such purpose.  The
      Executive acknowledges, understands and agrees that (i) the Bank
      operates a banking business in Brookline, Massachusetts and its
      vicinity, and therefore the geographic coverage of the restrictions
      contained herein are necessary for the protection of the Bank and are
      reasonable and (ii) the Executive’s experience and capabilities are such
      that the provisions of this Section 9 will not prevent the Executive
      from earning a livelihood.
    

    
      10        Other Benefits.  Nothing
      contained herein shall be deemed to exclude the Executive from any
      supplemental compensation, bonus, pension, insurance, severance pay or
      other benefit (including payments under the Current Plans) to which
      otherwise he might be or might become entitled as an employee of the
      Bank.
    

    
      
        

        

      

      
        
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      11        Additional
      Provisions.
    

    
      (a)       This agreement is a personal agreement and the rights and
      interests hereunder (except those of the Bank) may not be sold,
      transferred, assigned, pledged or hypothecated.  Benefits hereunder are
      not subject to alienation, anticipation or assignment by the Executive
      or any Beneficiary and are not subject to being attached or reached and
      applied by any creditor.  This Agreement shall be binding on the heirs,
      executors and administrators of the Executive and on the successors and
      assigns of the Bank.  During the Executive’s lifetime the parties hereto
      by mutual agreement may amend, modify or rescind this Agreement without
      the consent of any other person.
    

    
      (b)       This Agreement is intended to be unfunded and entered into by
      the Bank primarily for the purpose of providing supplemental retirement
      income for the Executive as one of a select group of management or
      highly compensated employees within the meaning of Section 201(2) of the
      Employee Retirement Income Security Act of 1974 as amended
      (“ERISA”).  Benefits are intended not to be taxable to the Executive
      under the Code until paid.  This Agreement shall be construed and
      interpreted in a manner consistent with the foregoing intentions.
    

    
      (c)       This Agreement shall not constitute an express or implied
      contract of employment between the Bank and the Executive.
    

    
      12        Arbitration.  Any
      controversy or claim arising out of or relating to this Agreement or the
      breach thereof shall be settled by arbitration in the Town of Brookline,
      Massachusetts in accordance with the rules then obtaining of the
      American Arbitration Association, and a judgment upon the award may be
      entered in any court having jurisdiction thereof.
    

    
      13        Governing Law.  This
      Agreement shall be governed by the laws of the Commonwealth of
      Massachusetts.
    

    
      14        Establishment of
      Rabbi Trust.  The Bank may establish a rabbi trust into which the
      Bank may contribute assets which shall be held therein, pursuant to the
      agreement which establishes such rabbi trust.  The contributed assets
      shall be subject to the claims of the Bank's creditors in the event of
      the Bank's “Insolvency” as defined in the agreement which establishes
      such rabbi trust, until the contributed assets are paid to the Executive
      and his Beneficiary in such manner and at such times as specified
      herein.   Any contribution(s) to the rabbi trust shall be made in
      accordance with the rabbi trust agreement.
    

    
      15        Source of Payments.  All
      payments provided under this Agreement shall be timely paid in cash or
      check from the general funds of the Bank or the assets of the rabbi
      trust.  The Company guarantees payment and provision of all amounts and
      benefits due to the Executive and, if such amounts and benefits are not
      timely paid or provided by the Bank or rabbi trust, such amounts and
      benefits shall be paid or provided by the Company.
    

    
      
        

        

      

      
        
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      IN WITNESS WHEREOF, the Company, Bank and the Executive have duly
      executed this Agreement as of December 18, 2008.
    

    
    	

        	
          BROOKLINE BANK
        
	

        	
           
        
	

        	
          
            By: /s/ Richard P. Chapman, Jr.
          

        
	

        	
          Richard P. Chapman, Jr.
        
	

        	
          Chairman and Chief Executive Officer
        
	

        	
           
        
	

        	
           
        
	

        	
           
        
	

        	
           
        
	

        	
          BROOKLINE BANCORP, INC.
        
	

        	
           
        
	

        	
          
            By: /s/ Richard P. Chapman, Jr.
          

        
	

        	
          Richard P. Chapman, Jr.
        
	

        	
          Chairman and Chief Executive Officer
        
	

        	
           
        
	

        	
           
        
	

        	
           
        
	

        	
          EXECUTIVE
        
	

        	
           
        
	

        	
          
            /s/ Charles H. Peck
          

        
	

        	
          Charles H. Peck
        
	

        	
          President, Brookline Bank
        


    

    
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