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                                                                     EXHIBIT 4.7

                        AMENDMENT TO GUARANTEE AGREEMENT

         This Amendment to Guarantee Agreement (the "Amendment") is made as of
December 23, 1999 by and between M&T Bank Corporation, a New York corporation,
and Bankers Trust Company, a New York banking corporation.

                                   WITNESSETH

         WHEREAS, M&T Bank Corporation, formerly known as First Empire State
Corporation, (the "Guarantor"), and Bankers Trust Company, as trustee (in such
capacity, the "Guarantee Trustee") previously entered into a Guarantee Agreement
dated as of January 31, 1997 (the "Guarantee Agreement") by which the Guarantor
agreed to make certain payments to the Holders of Capital Securities issued
pursuant to an Amended and Restated Trust Agreement dated as of January 31, 1997
by and between Guarantor, in its capacity as Depositor, Bankers Trust Company,
as property trustee, and Bankers Trust (Delaware), a Delaware banking
corporation, as Delaware trustee; and

         WHEREAS, the Guarantor has changed its corporate name from "First
Empire State Corporation" to "M&T Bank Corporation;" and

         WHEREAS, the Administrators of the Issuer Trust have changed the name
of the Issuer Trust from "First Empire Capital Trust I" to "M&T Capital Trust
I;" and

         WHEREAS, the Guarantor and the Guarantee Trustee desire to amend the
Guarantee Agreement to provide for the change of the name of the Guarantor from
"First Empire State Corporation" to "M&T Bank Corporation," and the name of the
Issuer Trust from "First Empire Capital Trust I" to "M&T Capital Trust I."

         NOW THEREFORE, in consideration of the agreements and obligations set
forth herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, each party to this Amendment, for
the benefit of the other parties and for the benefit of the Holders, hereby
amends the Guarantee Agreement, and agrees, intending to be legally bound, as
follows:

SECTION 1.  DEFINITIONS.

         1.1. For all purposes of this Amendment, except as otherwise expressly
provided, terms used but not defined in this Amendment shall have the meanings
assigned to them in the Guarantee Agreement.

         1.2. The definition of "Guarantor" in the preamble of the Guarantee
Agreement is amended to mean M&T Bank Corporation.


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         1.3. The definition of "Issuer Trust" in the preamble of the Guarantee
Agreement is amended to mean "M&T Capital Trust I."

SECTION 2.  MISCELLANEOUS.

         2.1. CONTINUING AGREEMENT. The Guarantee Agreement shall not be amended
by this Amendment except as specifically provided in this Amendment and, amended
as so specifically provided, the Guarantee Agreement shall remain in full force
and effect. References in the Guarantee Agreement to "this Guarantee Agreement"
shall be deemed to be references to the Guarantee Agreement as amended by this
Amendment.

         2.2. CONFLICTS. In the event of a conflict between the terms and
conditions of the Guarantee Agreement and the terms and conditions of this
Amendment, the terms and conditions of this Amendment shall prevail.

         2.3. COUNTERPART ORIGINALS. The parties may sign any number of copies
of this Amendment. Each signed copy shall be an original, but all of them
together represent the same agreement.

         2.4. HEADINGS, ETC. The headings of the sections of this Amendment have
been inserted for convenience of reference only, are not to be considered a part
hereof, and shall in no way modify or restrict any of the terms or provisions
hereof.

         IN WITNESS WHEREOF the parties have caused this Amendment to be
executed as of the day and year first above written.

                                            M&T BANK CORPORATION,
                                            as Guarantor



                                            By: /s/ Michael P. Pinto
                                                --------------------------------
                                                Michael P. Pinto
                                                Executive Vice President and
                                                Chief Financial Officer


                                            BANKERS TRUST COMPANY,
                                            as Guarantee Trustee,
                                            and not in its individual capacity



                                            By: /s/ Christopher D. Lew
                                                --------------------------------
                                                Christopher D. Lew
                                                Assistant Treasurer