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                                                                  EXHIBIT (4)(i)


                              M&T CAPITAL TRUST IV
                                 TRUST AGREEMENT


        THIS TRUST AGREEMENT, dated as of July 7, 2003, is by and among (i) M&T
Bank Corporation, a New York corporation (the "Depositor"), and (ii) The Bank of
New York (Delaware), a Delaware banking corporation, as trustee (the "Trustee").
The Depositor and the Trustee hereby agree as follows:

        1.      The trust created hereby (the "Trust") shall be known as "M&T
Capital Trust IV."

        2.      The Depositor hereby assigns, transfers, conveys and sets over
to the Trustee the sum of $10.00. The Trustee hereby acknowledges receipt of
such amount in trust from the Depositor, which amount shall constitute the
initial trust estate. The Trustee hereby declares that it will hold the trust
estate in trust for the Depositor.

        3.      It is the intention of the parties hereto that the Trust created
hereby constitute a statutory trust under Chapter 38 of Title 12 of the Delaware
Code, 12 Del. C. Section et seq. (the "Statutory Trust Act"), and that this
document constitutes the governing instrument of the Trust.

        4.      The Trustee is hereby authorized and directed to execute and
file a certificate of trust with the Delaware Secretary of State in accordance
with the provisions of the Statutory Trust Act.

        5.      The Depositor and the Trustee will enter into an amended and
restated Trust Agreement, satisfactory to each such party and substantially in
the form included as an exhibit to the 1933 Act Registration Statement (as
defined below), to provide for the contemplated operation of the Trust created
hereby and the issuance of the Capital Securities and Common Securities referred
to therein. Prior to the execution and delivery of such amended and restated
Trust Agreement, the Trustee shall not have any duty or obligation hereunder or
with respect to the trust estate, except as otherwise required by applicable law
or as may be necessary to obtain, prior to such execution and delivery, any
licenses, consents or approvals required by applicable law or otherwise.

        6.      The Depositor and the Trustee hereby authorize and direct the
Depositor, as the sponsor of the Trust, (i) to file with the Securities and
Exchange Commission (the "Commission") and execute, in each case on behalf of
the Trust, (a) the Registration Statement on Form S-3 (the "1933 Act
Registration Statement"), including any pre-effective or post-effective
amendments to the 1933 Act Registration Statement, relating to the registration
under the Securities Act of 1933, as amended, of the Capital Securities of the
Trust and possibly certain other securities and (b) a Registration Statement on
Form 8-A (the "1934 Act Registration Statement") (including all pre-effective
and post-effective amendments thereto) relating to the registration of the
Capital Securities of the Trust under the Securities Exchange Act of 1934, as
amended; (ii) to file with the New

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York Stock Exchange or any other national stock exchange or The Nasdaq National
Market (each, an "Exchange") and execute on behalf of the Trust one or more
listing applications and all other applications, statements, certificates,
agreements and other instruments as shall be necessary or desirable to cause the
Capital Securities to be listed on any of the Exchanges; (iii) to file and
execute on behalf of the Trust such applications, reports, surety bonds,
irrevocable consents, appointments of attorney for service of process and other
papers and documents as shall be necessary or desirable to register the Capital
Securities under the securities or blue sky laws of such jurisdictions as the
Depositor, on behalf of the Trust, may deem necessary or desirable and (iv) to
execute on behalf of the Trust that certain Underwriting Agreement relating to
the Capital Securities, among the Trust, the Depositor and the several
Underwriters named therein, substantially in the form included as an exhibit to
the 1933 Act Registration Statement.

        7.      This Trust Agreement may be executed in one or more
counterparts.

        8.      The number of Trustees initially shall be one (1) and thereafter
the number of Trustees shall be such number as shall be fixed from time to time
by a written instrument signed by the Depositor, who may increase or decrease
the number of Trustees; provided, however, that, to the extent required by the
Statutory Trust Act, one Trustee shall either be a natural person who is a
resident of Delaware or, if not a natural person, an entity which has its
principal place of business in the State of Delaware and otherwise meets the
requirements of applicable Delaware law. Subject to the foregoing, the Depositor
is entitled to appoint or remove without cause any Trustee at any time. The
Trustees may resign upon thirty (30) days' prior written notice to the
Depositor.

        9.      This Trust Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to conflict
of laws principles).





                            [Signature Page Follows]

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        IN WITNESS WHEREOF, the parties hereto, intending to be legally bound,
have caused this Trust Agreement to be duly executed as of the date first
written above.


                                            M&T BANK CORPORATION,
                                            as Depositor


                                            By: /s/ Michael S. Piemonte
                                                ------------------------
                                            Name:  Michael S. Piemonte
                                            Title: Senior Vice President


                                            The Bank of New York (Delaware),
                                            as Trustee

                                            By: /s/ Michael Santino
                                                ------------------------
                                            Name:  Michael Santino
                                            Title: Senior Vice President