Boston Private Financial Holdings (BPFH)

NOTICE OF CONVERSION

(To be executed by the Holder in order to convert the Series B Non-Cumulative Perpetual

Contingent Convertible Preferred Stock)

The undersigned hereby irrevocably elects to convert (the “Conversion”) the Series B Non-Cumulative Perpetual Contingent Convertible Preferred Stock (the “Series B Preferred Stock”) of Boston Private Financial Holdings, Inc. (hereinafter called the “Company”), represented by stock certificate No(s).              (the “Series B Preferred Stock Certificates”), into common stock, par value $1.00 per share, of the Company (the “Common Stock”) according to the conditions of the Articles of Amendment of the Series B Preferred Stock (the “Articles of Amendment”), as of the date written below. If shares of Common Stock are to be issued in the name of a person other than the undersigned, the undersigned will pay all transfer taxes payable with respect thereto, if any, and is delivering herewith the Series B Preferred Stock Certificates. No fee will be charged to the holder for any conversion, except for transfer taxes, if any. Each original Series B Preferred Stock Certificate is attached hereto (or evidence of loss, theft or destruction thereof).

The undersigned represents and warrants that all offers and sales by the undersigned of the Common Stock, if any, issuable to the undersigned upon conversion of the Series B Preferred Stock shall be made pursuant to registration of the Common Stock under the Securities Act of 1933, as amended (the “Act”), or pursuant to any exemption from registration under the Act.

Capitalized terms used but not defined herein shall have the meanings ascribed thereto in or pursuant to the Articles of Amendment.

Date of Conversion:                                                                                                   

Shares of Series B Preferred Stock to be Converted:                                               

Shares of Common Stock to be Issued:*                                                                  

Signature:                                                                                                                   

Name:                                                                                                                         

Address:**                                                                                                                  

Fax Number:                                                                                                               

B-36

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