AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON FEBRUARY 13, 2001

REGISTRATION NO. 333-48946

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1 ON FORM S-8 TO REGISTRATION STATEMENT
ON FORM S-4 UNDER THE SECURITIES ACT OF 1933

M&T BANK CORPORATION
- --------------------------------------------------------------------------------
(Exact name of registrant as specified in its charter)

New York 16-0968385
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(State or other jurisdiction of (I.R.S. Employer
incorporation or organization) Identification No.)

ONE M&T PLAZA
BUFFALO, NEW YORK 14203
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(Address, including zip code, of principal executive offices)

PROGRESSIVE BANK, INC. 1993 NON-QUALIFIED STOCK OPTION PLAN FOR DIRECTORS
PREMIER NATIONAL BANCORP, INC. 1995 INCENTIVE STOCK PLAN
(AS AMENDED AND RESTATED EFFECTIVE MAY 13, 1999)
PROGRESSIVE BANK, INC. INCENTIVE STOCK OPTION PLAN AMENDED AND RESTATED

- --------------------------------------------------------------------------------
(Full title of the plans)

RICHARD A. LAMMERT, ESQUIRE
SENIOR VICE PRESIDENT AND GENERAL COUNSEL
M&T BANK CORPORATION
ONE M&T PLAZA
BUFFALO, NEW YORK 14203
- --------------------------------------------------------------------------------
(Name and address of agent for service)

(716) 842-5390
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(telephone number, including area code, of agent for service)

COPY TO:
STEVEN KAPLAN, ESQ.
ARNOLD & PORTER
555 12TH STREET, N.W.
WASHINGTON, D.C. 20004
(202) 942-5998

PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

The following documents filed by M&T Bank Corporation (File No.
001-9861) ("M&T") with the Securities and Exchange Commission (the "Commission")
under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), are
incorporated herein by reference:

(a) M&T's Annual Report on Form 10-K for the year ended December 31,
1999.

(b) M&T's Quarterly Reports on Form 10-Q for the quarters ended
March 31, 2000, June 30, 2000 and September 30, 2000.

(d) M&T's Current Report on Form 8-K dated as of May 16, 2000.

(e) M&T's Current Report on Form 8-K dated as of July 9, 2000.

(f) M&T's Current Report on Form 8-K and 8-K/A dated as of October
6, 2000.

(g) The description of the common stock of M&T ("M&T Common Stock"),
contained in a registration statement on Form 8-A filed by M&T
on May 20, 1998, and any amendments or reports filed for the
purpose of updating such description.

All documents filed by M&T after the date of this Post-Effective
Amendment No. 1 pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange
Act, prior to the filing of a post-effective amendment which indicates that all
M&T Common Stock offered hereby has been sold or which deregisters such M&T
Common Stock then remaining unsold, shall be deemed to be incorporated in this
Post-Effective Amendment No. 1 by reference and shall be a part hereof from the
date of filing such documents. Any statement contained in a document
incorporated or deemed to be incorporated by reference in this Post-Effective
Amendment No. 1 shall be deemed to be modified or superseded for purposes of
this Post-Effective Amendment No. 1 to the extent that a statement contained
herein or in any other subsequently filed document which also is or is deemed to
be incorporated by reference in this Post-Effective Amendment No. 1 modifies or
supersedes such statement. Any such statement so modified or superseded shall
not be deemed, except as so modified or so superseded, to constitute a part of
this Post-Effective Amendment No. 1.

ITEM 4. DESCRIPTION OF SECURITIES.

Not applicable.

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ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

The consolidated financial statements of M&T incorporated in this
Registration Statement by reference to M&T's Annual Report on Form 10-K for the
year ended December 31, 1999, have been audited by PricewaterhouseCoopers LLP,
independent accountants, as outlined in their report thereon incorporated in
this document by reference. Such consolidated financial statements are
incorporated in this document by reference in reliance upon such report given
upon the authority of such firm as experts in accounting and auditing.

The audited consolidated financial statements of Keystone Financial,
Inc. ("Keystone") for the year ended December 31, 1999, included in Keystone's
Annual Report on Form 10-K for the year ended December 31, 1999 and incorporated
in this Registration Statement by reference to M&T's Current Report on Form 8-K
dated as of October 6, 2000, have been audited by Ernst & Young LLP, independent
auditors, as set forth in their report thereon incorporated by reference therein
and incorporated herein by reference. Such consolidated financial statements are
incorporated herein by reference in reliance upon such report given on the
authority of such firm as experts in accounting and auditing.

Documents incorporated herein by reference in the future will include
financial statements, related schedules (if required) and auditors' reports,
which financial statements and schedules will have been audited to the extent
and for the periods set forth in such reports by the firm or firms rendering
such reports, and, to the extent so audited and consent to incorporation by
reference is given, will be incorporated herein by reference in reliance upon
such reports given upon the authority of such firms as experts in accounting and
auditing.

Richard A. Lammert, Esq., Senior Vice President and General Counsel of
M&T, has delivered a legal opinion to the effect that the issuance and sale of
the M&T common stock offered hereby was duly authorized by M&T and that such M&T
common stock will be validly issued, fully paid and nonassessable when issued
upon the exercise of options. As of February 12, 2001, Mr. Lammert was the
beneficial owner of 62,270 shares of M&T common stock and held options granted
under the M&T Bank Corporation 1983 Stock Option Plan covering 140,000 shares
of M&T common stock, 100,500 of which are currently exercisable.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

Section 721 and 722 of the New York Business Corporation Law ("NYBCL")
provide for indemnification of directors and officers. Section 721 of New York
law provides that the statutory provisions under New York law are not exclusive
of any other rights to which a director or officer seeking indemnification would
be entitled.

Section 722 of the NYBCL provides that a corporation may indemnify a
director or officer of the corporation who is made a party, or threatened to be
made a party, in a civil or criminal

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proceeding arising out of activities undertaken at the request of the
corporation (including action on behalf of another corporation, partnership,
joint venture, trust, employee benefit plan or other business enterprise)
against judgments, fines, amounts paid in settlement and reasonable expenses, if
the director or officer acted in good faith for a purpose which he reasonably
believed to be in, or, in the case of service for any other corporation,
partnership, joint venture, trust, employee benefit plan or other business
enterprise, not opposed to, the best interests of the corporation. To be
indemnified with respect to criminal proceedings, the director or officer must
also have had no reasonable cause to believe that his or her conduct was
unlawful. In the case of a claim by or in the right of the corporation
(including stockholder derivative suits), there is no indemnification under New
York law for threatened actions or a pending action otherwise settled or
disposed of, and no indemnification of expenses is permitted, if the director or
officer is adjudged liable to the corporation unless and only to the extent a
court determines that, despite such adjudication but in view of all the
circumstances, such indemnification is nonetheless proper.

The certificate of incorporation of M&T provides that M&T will indemnify
to the maximum extent permissible under New York law its officers and directors
for liability arising out of their actions in such capacity.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED.

Not applicable.

ITEM 8. EXHIBITS.

The exhibits listed on the Exhibit Index on page II-9 of this
Post-Effective Amendment No. 1 on Form S-8 to Registration Statement on Form S-4
have been previously filed, are filed herewith or are incorporated herein by
reference to other filings.

ITEM 9. UNDERTAKINGS.

M&T hereby undertakes:

1. To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

(a) To include any prospectus required by Section 10(a)(3)
of the Securities Act of 1933, as amended;

(b) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement
(or the most recent post-effective amendment thereof)
which, individually or in the aggregate, represent a
fundamental change in the information set forth in the
registration statement.

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Notwithstanding the foregoing, any increase or decrease
in volume of securities offered (if the total dollar
value of securities offered would not exceed that which
was registered) and any deviation from the low or high
end of the estimated maximum offering range may be
reflected in the form of prospectus filed with the
Commission pursuant to Rule 424(b) if, in the aggregate,
the changes in volume and price represent no more than a
20% change in the maximum aggregate offering price set
forth in the "Calculation of Registration Fee" table in
the effective registration statement;

(c) To include any material information with respect to the
plan of distribution not previously disclosed in the
registration statement or any material change to such
information in the registration statement.

Provided, however, that the undertakings set forth in paragraphs
1(a) and 1(b) above do not apply if the information required to
be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed by M&T pursuant to Section
13 or 15(d) of the Exchange Act, which are incorporated by
reference in this registration statement.

2. That, for the purpose of determining any liability under the
Securities Act of 1933, as amended, each such post-effective
amendment shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of
such securities at that time shall be deemed to be the initial
bona fide offering thereof.

3. To remove from registration by means of a post-effective
amendment any of the securities being registered which remain
unsold at the termination of the offering.

4. That, for purposes of determining any liability under the
Securities Act of 1933, as amended, each filing of M&T's annual
report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act, that is incorporated by reference in this
registration statement shall be deemed to be a new registration
statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.

5. Insofar as indemnification for liabilities arising under the
Securities Act of 1933, as amended, may be permitted to
directors, officers and controlling persons of M&T pursuant to
the foregoing provisions, or otherwise, M&T has been advised
that in the opinion of the Commission such indemnification is
against public policy as expressed in the Securities Act and is,
therefore, unenforceable. In the event that a claim for
indemnification against such liabilities (other than the payment
by M&T of

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expenses incurred or paid by a director, officer or controlling
person of M&T in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling
person in connection with the securities being registered, M&T
will, unless in the opinion of its counsel the matter has been
settled by controlling precedent, submit to a court of
appropriate jurisdiction the question whether such
indemnification by it is against public policy as expressed in
the Securities Act and will be governed by the final
adjudication of such issue.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, M&T
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Post-Effective
Amendment No. 1 on Form S-8 to Registration Statement on Form S-4 to be signed
on its behalf by the undersigned, thereunto duly authorized, in the City of
Buffalo, State of New York, on February 13, 2001.

M&T BANK CORPORATION

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

Pursuant to the requirements of the Securities Act of 1933, this
Post-Effective Amendment No. 1 on Form S-8 to Registration Statement on Form S-4
has been signed by the following persons in the capacities indicated on February
13, 2001:

Signature Title

* Chairman of the Board, President and Chief
----------------------------- Executive Officer (Principal Executive Officer)
Robert G. Wilmers

/s/ Michael P. Pinto Executive Vice President and Chief Financial
----------------------------- Officer (Principal Financial Officer)
Michael P. Pinto

/s/ Michael R. Spychala Senior Vice President and Controller (Principal
----------------------------- Accounting Officer)
Michael R. Spychala

* Director
----------------------------
William F. Allyn

* Director
----------------------------
Brent D. Baird

* Director
----------------------------
John H. Benisch

* Director
----------------------------
Robert J. Bennett

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* Director
----------------------------
C. Angela Bontempo

* Director
----------------------------
Robert T. Brady

* Director
----------------------------
Patrick J. Callan

* Vice Chairman of the Board
----------------------------
Carl L. Campbell

* Director
----------------------------
R. Carlos Carballada

Director
----------------------------
T. Jefferson Cunningham III

* Director
----------------------------
Donald Devorris

* Director
----------------------------
Richard E. Garman

* Director
----------------------------
James V. Glynn

* Director
----------------------------
Daniel R. Hawbaker

* Director
----------------------------
Patrick W.E. Hodgson

* Director
----------------------------
Samuel T. Hubbard, Jr.

* Director
----------------------------
Richard G. King

* Director
----------------------------
Reginald B. Newman, II

* Director
----------------------------
Peter J. O'Donnell, Jr.

* Director
----------------------------
Jorge G. Pereira

* Director
----------------------------
Robert E. Sadler, Jr.

* Director
----------------------------
Stephen G. Sheetz

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* Director
----------------------------
John L. Vensel

* Director
----------------------------
Herbert L. Washington

* By /s/ Richard A. Lammert February 13, 2001
---------------------------
(Attorney-in-fact)

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INDEX TO EXHIBITS
-----------------

Exhibit 4.1 Progressive Bank, Inc. 1993 Non-Qualified Stock Option Plan for Directors, incorporated
by reference to Exhibit 10.9 to the Annual Report on Form 10-K, for the fiscal year
ended December 31, 1994, file No. 0-15025, of Progressive Bank, Inc.

Exhibit 4.2 Premier National Bancorp, Inc. 1995 Incentive Stock Plan (as amended and restated effective
May 13, 1999) incorporated by reference to Exhibit 10.4 to Premier's Annual Report on Form 10-K
for the year ended December 31, 1999, file No. 1-13213.

Exhibit 4.3 Progressive Bank, Inc. Incentive Stock Option Plan Amended and Restated, incorporated by
reference to Exhibit 10-2 to the Annual Report on Form 10-K, file No. 0-15025 of
Progressive Bank Inc., filed on March 22, 1998.

Exhibit 5 Opinion of Richard A. Lammert, Esq., filed herewith.

Exhibit 23.1 Consent of Richard A. Lammert, Esq., included in the opinion filed as Exhibit 5 hereto.

Exhibit 23.2 Consent of PricewaterhouseCoopers LLP, filed herewith.

Exhibit 23.3 Consent of Ernst & Young LLP, filed herewith.

Exhibit 24 Powers of Attorney of certain directors and officers of M&T, previously filed as
Exhibit 24 to the Registration Statement on Form S-4 (File No. 333-48946) by M&T Bank
Corporation.

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