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                                                                    EXHIBIT 4.48

                          SUPPLEMENTAL INDENTURE NO. 2

                               (SUBORDINATED DEBT)

         SUPPLEMENTAL INDENTURE NO. 2, dated as of April 1, 2003 (this "Second
Supplemental Indenture"), by and between M&T Bank Corporation, a New York
banking corporation (the "Company") and successor by merger to Allfirst
Financial Inc. ("Allfirst"), having its principal executive office at One M&T
Plaza, Buffalo, New York 14203, and Deutsche Bank Trust Company Americas, a New
York banking corporation and formerly known as Bankers Trust Company, as trustee
(the "Trustee").

                                    RECITALS

         1.       The Trustee is the trustee under that certain Indenture, dated
as of May 15, 1992, as supplemented by Supplemental Indenture No. 1, dated as of
September 15, 1999 (the "Indenture"), between the Trustee and Allfirst, as
issuer from time to time of subordinated debt securities. Under the Indenture,
Allfirst issued $200,000,000 aggregate principal amount of 7.20% Subordinated
Notes due July 1, 2007 and $100,000,000 aggregate principal amount of 6.875%
Subordinated Notes due June 1, 2009 (collectively, the "Outstanding Notes").

         2.       As of the date hereof, Allfirst, a Delaware corporation,
merged with and into the Company.

         3.       Pursuant to Section 8.1 of the Indenture, the Company now
wishes expressly to assume all of Allfirst's obligations under the Indenture and
the Outstanding Notes.

         NOW, THEREFORE, in consideration of the premises, the agreements
contained herein and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto agree as
follows:

         1.       Certain Definitions; Interpretation; Recitals. A capitalized
term used in this Second Supplemental Indenture (including the above Recitals)
without definition and defined in the Indenture shall have the meaning given it
in the Indenture. All references in the Indenture to "this Indenture" or words
of similar import, and the terms "hereby", "hereof", "hereunder", "herein" and
any similar terms, as used in the Indenture, shall be deemed to refer to the
Indenture as supplemented by this Second Supplemental Indenture. The above
Recitals are an integral part of this Second Supplemental Indenture.

         2.       Assumption. Pursuant to Section 8.1 of the Indenture, the
Company hereby expressly assumes the due and punctual payment of the principal
of, premium, if any, and interest on all the Securities (which consist of the
Outstanding Notes), and the exercise of every right and power under and the
performance of every covenant of the Indenture on the part of Allfirst to be
performed or observed, as fully and completely as if the Company had originally
executed and delivered the Indenture to the Trustee and issued the Outstanding
Notes.

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         3.       Amendments. From and after the date of this Second
Supplemental Indenture, all references in the Indenture and in the Outstanding
Notes to "First Maryland Bancorp," "Allfirst Financial, Inc." or "the Company"
shall be references to M&T Bank Corporation, a New York corporation and the
successor by merger to Allfirst.

         4.       Representations, Warranties, Etc. The Company represents and
warrants to and covenants with the Trustee as follows:

         (a)      The Company is a banking corporation duly formed, validly
existing and in good standing under the laws of the State of New York, with the
power and authority to own its assets and conduct its business as currently
conducted, to enter into this Second Supplemental Indenture and to perform every
covenant and obligation to be performed by it under the Indenture and the
Outstanding Notes.

         (b)      Allfirst has been duly and validly merged into the Company,
and the Company has succeeded to all of the rights, privileges, duties and
responsibilities of Allfirst, under the laws of the States of New York and
Delaware.

         (c)      The execution, delivery and performance of this Second
Supplemental Indenture have been duly authorized by all necessary action on the
part of the Company, and this Second Supplemental Indenture represents the valid
and binding obligation of the Company, enforceable against the Company in
accordance with its terms.

         (d)      No Event of Default, and no event which, after notice or lapse
of time or both, would become an Event of Default, has happened and is
continuing as a result of the merger of Allfirst into the Company or otherwise.

         5.       Other Agreements. (a) Except as expressly supplemented or
amended hereby, all of the terms, provisions and conditions of the Indenture and
the Outstanding Notes are ratified and confirmed and shall remain in full force
and effect. This Second Supplemental Indenture shall in no way operate as a
novation, release or discharge of any of the obligations the Company under, or
of any of the provisions of, the Indenture and the Outstanding Notes.

         (b)      This Second Supplemental Indenture does not, and shall not be
deemed to, constitute a waiver of any past, present or future defaults by the
Company under the Indenture or the Outstanding Notes, and the Trustee expressly
reserves all rights and remedies available to it under the Indenture, the
Outstanding Notes and under applicable law for the benefit of Holders from time
to time.

         (c)      This Second Supplemental Indenture shall be governed by and
construed in accordance with the laws of the State of New York.

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         (d)      Provided that each party executes a copy hereof, this Second
Supplemental Indenture may be executed in two or more counterparts, each of
which shall be deemed an original but all of which when taken together shall
constitute one and the same agreement.

         IN WITNESS WHEREOF, the parties hereto have caused this Second
Supplemental Indenture to be duly executed, and their respective corporate seals
to be hereunto affixed and attested, all as of the date first written above.

[Corporate Seal]                            M&T BANK CORPORATION

Attest:

By:  /s/ Marie King                     By: /s/ Michael S. Piemonte
    ----------------------------            ------------------------------------
         Name: Marie King                       Name: Michael S. Piemonte
         Title: Corporate Secretary             Title: Senior Vice President

[Corporate Seal]                       DEUTSCHE BANK TRUST COMPANY
                                          AMERICAS

Attest:

By:  /s/ Irina Golovashchuk            By: /s/ Susan Johnson
    ----------------------------           ------------------------------------
         Name: Irina Golovashchuk              Name: Susan Johnson
         Title: Associate                      Title: Vice President

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STATE OF NEW YORK               )
                                ) ss:
COUNTY OF ERIE                  )

         On April 25, 2003, before me personally appeared Michael S. Piemonte,
to me known or satisfactorily proven, who, being by me duly sworn, did depose
and say: that he is a Senior Vice President of M&T Bank Corporation, one of the
corporations described in and which executed the foregoing instrument; that he
knows the seal of said corporation; that the seal affixed to said instrument is
such corporate seal; that it was so affixed by authority of the Board of
Directors of said corporation; and that he signed his name thereto by like
authority.

                                /s/ Brian R. Yoshida
                                ------------------------------------
                                Notary Public
                                State of New York

                                My Commission Expires: 3/29/07

STATE OF NEW YORK               )
                                )
COUNTY OF NEW YORK              )

         On April 28, 2003, before me personally appeared Susan Johnson, to me
known or satisfactorily proven, who, being by me duly sworn, did depose and say:
that she is a Vice President of Deutsche Bank Trust Company Americas, one of the
corporations described in and which executed the foregoing instrument; that she
knows the seal of said corporation; that the seal affixed to said instrument is
such corporate seal; that it was so affixed by authority of the Board of
Directors of said corporation; and that she signed her name thereto by like
authority.

                                /s/ Annie Jaghatspanyan
                                ----------------------------------
                                Notary Public
                                State of New York

                                My Commission Expires: July 30, 05

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