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                                                                   EXHIBIT 15.1
 
The Stockholders and Board of Directors
State Street Boston Corporation
 
  We are aware of the incorporation by reference in the Registration Statement
on Form S-3 of State Street Boston Corporation for the registration of 923,072
shares of its common stock of our reports dated April 12, 1996, July 12, 1996
and October 11, 1996 relating to the unaudited consolidated interim financial
statements of State Street Boston Corporation that are included in its Forms
10-Q for the quarters ended March 31, 1996, June 30, 1996 and September 30,
1996.
 
  Pursuant to Rule 436(c) of the Securities Act of 1933 our reports are not a
part of the registration statement prepared or certified by accountants within
the meaning of Section 7 or 11 of the Securities Act of 1933.
 
                                          Ernst & Young LLP
 
Boston, Massachusetts
November 26, 1996
