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                                                                       EXHIBIT 8




                        [Sullivan & Cromwell Letterhead]





                                                               January 27, 1997




KeyCorp Institutional Capital A,
   c/o KeyCorp,
      127 Public Square,
         Cleveland, Ohio 44114.

Ladies and Gentlemen:

     As special tax counsel to KeyCorp Institutional Capital A (the "Issuer")
and KeyCorp in connection with the exchange offer by the Issuer of $350,000,000
of its 7.826% Capital Securities pursuant to a Preliminary Prospectus dated
February __, 1997 (the "Prospectus"), and assuming (i) the holder of the Common
Securities of the Issuer will have "substantial assets" (other than the Common
Securities) within the meaning of Treasury Regulations Section 301.7701-2(d)(2)
and (ii) the operative documents described in the Prospectus will be performed
in accordance with the terms described therein, we hereby confirm to you our
opinion as


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KeyCorp Institutional Capital A                                             -2-


set forth under the heading "Certain Federal Income Tax Consequences" in the
Prospectus, subject to the limitations set forth therein.

        We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the references to us under the heading "Certain
Federal Income Tax Consequences" in the Prospectus. In giving such consent, 
we do not thereby admit that we are in the category of persons whose consent 
is required under Section 7 of the Act.

                                              Very truly yours,

                                              SULLIVAN & CROMWELL




