EXHIBIT 5

                                                         HARRIS
                                                         BEACH &
                                                         WILCOX
August 6, 1998                                           A LIMITED LIABILITY
                                                         PARTNERSHIP
                                                         ATTORNEYS AT LAW

                                                         119 EAST SENECA STREET
                                                         P.O. BOX 580
                                                         ITHACA, NEW YORK. 14850
                                                         (607) 273-6444
                                                         (607) 273-6802 (Fax)
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Tompkins County Trustco, Inc.
The Commons, P.O. Box 460
Ithaca, New York 14851

Ladies and Gentlemen:

         This  opinion is  furnished to you in  connection  with a  registration
statement  on Form  S-8 (the  "Registration  Statement")  to be  filed  with the
Securities and Exchange  Commission (the "Commission")  under the Securities Act
of 1933, as amended,  for the  registration  of 240,000  shares of common stock,
$.10 par value per share (the "Shares"), of Tompkins County Trustco, Inc., a New
York corporation (the "Company"), issuable under the Company's 1998 Stock Option
Plan (the "Plan").

         We have acted as counsel  for the Company in  connection  with the Plan
and are familiar with the actions taken by the Company in connection  therewith.
For purposes of this opinion we have examined the  Registration  Statement,  the
Plan and such other documents as we have deemed appropriate.

         Based upon the  foregoing,  we are of the  opinion  that (i) the Shares
have  been  duly  authorized  and  (ii)  the  Shares,  when  issued  and sold in
accordance with the terms of the Plan, will have been validly issued and will be
fully paid and non-assessable.

         We hereby  consent  to your  filing  this  opinion as an exhibit to the
Registration Statement.


                                             Very truly yours,

                                             HARRIS BEACH & WILCOX, LLP


                                             By:
                                                -----------------
                                                  Mark B. Wheeler