[Letterhead of Ropes & Gray]
                                                                     Exhibit 8.1

January 21, 2003




State Street Capital Trust II
c/o State Street Bank and Trust Company N.A.
61 Broadway, 15th Floor
New York, New York  10006

State Street Corporation
225 Franklin Street
Boston, Massachusetts 02110

         Re:   State Street Corporation
               State Street Capital Trust II
               Registration Statement
               File No. 333-98267 and
               Definitive Prospectus Supplement dated January 14, 2003



Ladies and Gentlemen:

         We have acted as counsel to State Street Capital Trust II, a statutory
trust formed under the laws of the State of Delaware (the "Trust"), and State
Street Corporation, a Massachusetts corporation (the "Corporation") and
Depositor of the Trust, in connection with a Registration Statement on Form S-3,
filed by the Corporation and the Trust on August 16, 2002 with the Securities
and Exchange Commission (as amended by Post-Effective Amendment No. 1 thereto
filed on November 21, 2002, the "Registration Statement") pursuant to the
Securities Act of 1933, as amended (the "1933 Act"), including the prospectus
dated November 27, 2002 (the "Prospectus") contained therein and prospectus
supplement relating to the Floating Rate Medium Term Capital Securities dated
January 14, 2003 (the "Prospectus Supplement") file on January 15, 2003 under
Rule 424(b) under the 1933 Act in connection therewith. The Registration
Statement relates, among other things, to the registration of the Floating Rate
Medium Term Capital Securities of the Trust (the "Capital Securities"), the
floating rate medium term junior subordinated debentures of the Corporation (the
"Junior Subordinated Debentures"), and the capital securities guarantee (the
"Guarantee") of the Corporation with respect to the Capital Securities. Unless
the context otherwise requires, capitalized terms used herein but not defined
have the meanings set forth in the Prospectus and Prospectus Supplement.



State Street Corporation                -2-                    January 21, 2003
State Street Capital Trust II



         In rendering our opinion, we have examined the forms of Amended and
Restated Trust Agreement, Guarantee and Junior Subordinated Debenture identified
to us as those to be employed in connection with the issuance of the Capital
Securities and Junior Subordinated Debentures (collectively, the "Forms of
Agreement"), the original Declaration of Trust dated March 25, 1998, the
Certificate of Trust filed with the Delaware Secretary of State on March 25,
1998 and the Supplemental Indenture of the Company under which the Subordinated
Debentures are to be issued (together with the Forms of Agreement, the
"Operative Agreements") and other relevant documents and have made such
inquiries as were necessary or appropriate to enable us to render this opinion.
With your permission we have assumed that all operations under the Operative
Agreements will be in accordance with their terms and as described in the
Prospectus and Prospectus Supplement, and that the SPACES and separate PACES
issued by the Corporation will not be issued to or held by any holders of the
Capital Securities.

         Based on the foregoing, we hereby confirm that the discussion of
certain United States federal income tax consequences of the purchase, ownership
and disposition of Capital Securities contained under the caption "Certain
United States Federal Income Tax Considerations" in the Prospectus Supplement is
materially accurate, subject to the limitations there stated.

         We hereby consent to the use of our name under the caption "Legal
Matters" in the Prospectus. In giving this consent, we do not hereby admit that
we are within the category of persons whose consent is required under Section 7
of the 1933 Act, or the rules and regulations of the Securities and Exchange
Commission thereunder.



Very truly yours,

/s/ Ropes & Gray

Ropes & Gray