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                                                                    EXHIBIT 99.1

November 13, 2002


VIA EDGAR
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C.  20549

Re:  BOSTON PRIVATE FINANCIAL HOLDINGS, INC. CERTIFICATION PURSUANT TO
     18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE
     SARBANES-OXLEY ACT OF 2002

     The undersigned officer of Boston Private Financial Holdings, Inc. (the
"Company") hereby certifies that the Company's quarterly report on Form 10-Q for
the quarterly period ended September 30, 2002 (the "Report"), as filed with the
Securities and Exchange Commission on the date hereof, fully complies with the
requirements of Section 13(a) or 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended, and that the information contained in the
Report fairly presents, in all material respects, the financial condition and
results of operations of the Company. This certification is provided solely
pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, and shall not be deemed a part of the Report or
"filed" for any purpose whatsoever.

     Sincerely,


     /s/  Timothy L. Vaill
     -------------------------
     Timothy L. Vaill
     Chairman and Chief Executive Officer

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