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                                    FORM 8-A

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   ----------

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


                           COMMUNITY BANK SYSTEM, INC.
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)


              DELAWARE                                           161213679
      -----------------------                                -------------------
      (State of incorporation                                 (I.R.S. Employer
          or organization)                                   Identification No.)


5790 WIDEWATERS PARKWAY, DEWITT, NEW YORK                          13214
- -----------------------------------------                        ----------
(Address of principal executive offices)                         (Zip Code)


Securities to be registered pursuant to Section 12(b) of the Act:

      Title of each class                         Name of each exchange on which
      To be so registered                         each class is to be registered
- -------------------------------                   ------------------------------
     Stock Purchase Rights                           New York Stock Exchange


If this form relates to the registration of a class of securities pursuant to
Section 12(b) of the Exchange Act and is effective pursuant to General
Instruction A.(c), check the following box.  [X]


If this form relates to the registration of a class of securities pursuant to
Section 12(g) of the Exchange Act and is effective pursuant to General
Instruction A.(d), check the following box.  [ ]


Securities Act registration statement file number to which this form relates:

                     ______________________ (if applicable)


Securities to be registered pursuant to Section 12(g) of the Act:

                                      None


                             Exhibit Index on Page 5

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ITEM 1. DESCRIPTION OF REGISTRANT'S SECURITIES TO BE REGISTERED

     On February 21, 1995, the Board of Directors of Community Bank System,
Inc., a Delaware corporation (the "Company"), declared a dividend payable
February 24, 1995 of one right (a "Right") for each outstanding share of common
stock of the Company ("Common Stock") held of record at the close of business on
February 21, 1995 (the "Record Time"), or issued thereafter and prior to the
Separation Time (as hereinafter defined). The Rights are issued pursuant to a
Stockholder Protection Rights Agreement, dated as of February 21, 1995 (the
"Rights Agreement"), between the Company and Community Bank, National
Association, a national banking organization, as Rights Agent (the "Rights
Agent"). Each Right entitles its registered holder to purchase from the Company,
after the Separation Time, one share of Common Stock for $42.50 (the "Exercise
Price"), subject to adjustment.

     The Rights will be evidenced by the Common Stock certificates until the
close of business on the earlier of (either, the "Separation Time") (i) the
tenth day (or such later date as the Board of Directors of the Company may from
time to time fix by resolution adopted prior to the Separation Time that would
otherwise have occurred) after the date on which any Person (as defined in the
Rights Agreement) (other than the Company, a majority-owned subsidiary of the
Company or an employee stock ownership or other employee benefit plan of the
Company or a majority-owned subsidiary of the Company) commences a tender or
exchange offer which, if consummated, would result in such Person's becoming the
Beneficial Owner of 15% or more of the outstanding shares of Common Stock (any
Person having such Beneficial Ownership being referred to as an "Acquiring
Person") and (ii) the first date (the "Flip-in Date") of public announcement by
the Company or an Acquiring Person that an Acquiring Person has become such,
other than as a result of a Flip-over Transaction or Event (as defined below);
provided that if the foregoing results in the Separation Time being prior to the
Record Time, the Separation Time shall be the Record Time and provided further
that if a tender or exchange offer referred to in clause (i) is canceled,
terminated or otherwise withdrawn prior to the Separation Time, such offer shall
be deemed never to have been made. The Rights Agreement provides that, until the
Separation Time, the Rights will be transferred with and only with the Common
Stock. Common Stock certificates issued after the Record Time but prior to the
Separation Time shall evidence one Right for each share of Common Stock
represented thereby and shall contain a legend incorporating by reference the
terms of the Rights Agreement (as such may be amended from time to time).
Notwithstanding the absence of the aforementioned legend, certificates
evidencing shares of Common Stock outstanding at the Record Time shall also
evidence one Right for each share of


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Common Stock evidenced thereby. Promptly following the Separation Time, separate
certificates evidencing the Rights ("Rights Certificates") will be mailed to
holders of record of Common Stock at the Separation Time.

     The Rights will not be exercisable until the Business Day (as defined in
the Rights Agreement) following the Separation Time. The Rights will expire on
the earliest of (i) the Exchange Time (as defined below), (ii) the close of
business on February 21, 2005 and (iii) the date on which the Rights are
redeemed as described below (in any such case, the "Expiration Time").

     The Exercise Price and the number of Rights outstanding, or in certain
circumstances the securities purchasable upon exercise of the Rights, are
subject to adjustment from time to time to prevent dilution in the event of a
Common Stock dividend on, or a subdivision or a combination into a smaller
number of shares of, Common Stock, or the issuance or distribution of any
securities or assets in respect of, in lieu of or in exchange for Common Stock.

     In the event that prior to the Expiration Time, a Flip-in Date occurs, the
Company shall take such action as shall be necessary to ensure and provide that
each Right (other than Rights beneficially owned by the Acquiring Person or any
affiliate or associate thereof, which Rights shall become void) shall constitute
the right to purchase from the Company, upon the exercise thereof in accordance
with the terms of the Rights Agreement, that number of shares of Common Stock of
the Company having an aggregate Market Price, on the date of the public
announcement of an Acquiring Person's becoming such (the "Stock Acquisition
Date") that gave rise to the Flip-in Date, equal to twice the Exercise Price for
an amount in cash equal to the then current Exercise Price. In addition, the
Board of Directors of the Company may, at its option, at any time after a
Flip-in Date and prior to the time that an Acquiring Person becomes the
Beneficial Owner of more than 50% of the outstanding shares of Common Stock,
elect to exchange all (but not less than all) of the then outstanding Rights
(other than Rights Beneficially Owned by the Acquiring Person or any affiliate
or associate thereof, which Rights become void) for shares of Common Stock at an
exchange ratio of one share of Common Stock per Right, appropriately adjusted to
reflect any stock split, stock dividend or similar transaction occurring after
the date of the Separation Time (the "Exchange Ratio"). Immediately upon such
action by the Board of Directors (the "Exchange Time"), the right to exercise
the Rights will terminate and each Right will thereafter represent only the
right to receive a number of shares of Common Stock equal to the Exchange Ratio.

     In the event that prior to the Expiration Time the Company enters into,
consummates or permits to occur a transaction or series of transactions on or


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after the Stock Acquisition Date in which, directly or indirectly, (A) the
Company shall consolidate or merge with any other Person or (B) the Company
shall sell or otherwise transfer (or one or more of its Subsidiaries shall sell
or otherwise transfer) assets (i) aggregating more than 50% of the assets
(measured by either book value or fair market value) or (ii) generating more
than 50% of the operating income or cash flow, of the Company and its
subsidiaries (taken as a whole) to any other Person (other than the Company or
one or more of its wholly owned subsidiaries) or to two or more such Persons
which are affiliated or otherwise acting in concert or (C) any Acquiring Person
shall (i) obtain, with or without consideration, over any period of 12
consecutive calendar months, any additional shares of any class of capital stock
of the Company or any of its Subsidiaries equal in the aggregate to more than 1%
of the outstanding shares of such class, or securities exercisable or
exchangeable for or convertible into more than 1% of the outstanding shares of
any class of capital stock of the Company or any of its Subsidiaries (in each
case other than as part of a pro rata distribution to all holders of such stock
or pursuant to the exercise of rights or warrants, or the conversion or exchange
of securities, issued pro rata in such a distribution), (ii) sell, purchase,
lease, exchange, mortgage, pledge, transfer or otherwise acquire or dispose of,
to, from, or with, as the case may be, the Company or any of its Subsidiaries,
over any period of 12 consecutive calendar months, assets (x) having an
aggregate fair market value of more than $15,000,000 or (y) on terms and
conditions less favorable to the Company than the Company would be able to
obtain through arm's-length negotiations with an unaffiliated third party, (iii)
receive any compensation for services from the Company or any of its
Subsidiaries, other than compensation for full-time employment as a regular
employee at rates in accordance with the Company's (or its Subsidiaries') past
practices, or (iv) receive the benefit, directly or indirectly (except
proportionately as a shareholder), over any period of 12 consecutive calendar
months, of any loans, advances, guarantees, pledges, insurance, reinsurance or
other financial assistance or any tax credits or other tax advantage provided by
the Company or any of its Subsidiaries involving an aggregate principal amount
in excess of $5,000,000 or an aggregate cost or transfer of benefits from the
Company or any of its Subsidiaries in excess of $5,000,000 or, in any case, on
terms and conditions less favorable to the Company than the Company would be
able to obtain through arm's-length negotiations with a third party, or (D) as a
result of any reclassification of securities (including any reverse stock
split), or recapitalization, of the Company, or any merger or consolidation of
the Company with any of its Subsidiaries or any other transaction or series of
transactions (whether or not with or into or otherwise involving an Acquiring
Person), the proportionate share of the outstanding shares of any class of
equity or convertible securities of the Company or any of its Subsidiaries which
is directly or indirectly owned by any Acquiring Person is increased by more
than 1%, then the Company shall


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take such action as shall be necessary to ensure, and shall not enter into,
consummate or permit to occur such Flip-over Transaction or Event until it shall
have entered into a supplemental agreement with the Person engaging in such
Flip-over Transaction or Event (the "Flip-over Entity"), for the benefit of the
holders of the Rights, providing, that upon consummation or occurrence of the
Flip-over Transaction or Event (i) each Right shall thereafter constitute the
right to purchase from the Flip-over Entity, upon exercise thereof in accordance
with the terms of the Rights Agreement, that number of shares of common stock of
the Flip-over Entity having an aggregate Market Price on the date of
consummation or occurrence of such Flip-over Transaction or Event equal to twice
the Exercise Price for an amount in cash equal to the then current Exercise
Price and (ii) the Flip-over Entity shall thereafter be liable for, and shall
assume, by virtue of such Flip-over Transaction or Event and such supplemental
agreement, all the obligations and duties of the Company pursuant to the Rights
Agreement. For purposes of the foregoing description, the term "Acquiring
Person" shall include any Acquiring Person and its Affiliates and Associates
(other than the Company, a wholly owned Subsidiary of the Company or an employee
stock ownership or other employee benefit plan of the Company or a wholly owned
Subsidiary of the Company), counted together as a single Person (a "Flip-over
Transaction or Event").

     The Board of Directors of the Company may, at its option, at any time prior
to the Flip-in Date, redeem all (but not less than all) the then outstanding
Rights at a price (calculated to the nearest one one-hundredth of a cent) equal
to the Exercise Price, as in effect at the Redemption Time, divided by 8500
(initially $0.01 per Right) (the "Redemption Price"), as provided in the Rights
Agreement. Immediately upon the action of the Board of Directors of the Company
electing to redeem the Rights, without any further action and without any
notice, the right to exercise the Rights will terminate and each Right will
thereafter represent only the right to receive the Redemption Price in cash for
each Right so held.

     The holders of Rights, solely by reason of their ownership of Rights, have
no rights as stockholders of the Company, including, without limitation, the
right to vote or to receive dividends.

     The Rights will not prevent a takeover of the Company. The Rights, however,
may have certain anti-takeover effects. The Rights may cause substantial
dilution to a person or group that acquires 15% or more of the Common Stock
unless the Rights are first redeemed by the Board of Directors of the Company.
Nevertheless, the Rights should not interfere with a transaction that is in the
best interests of the Company and its stockholders on or prior to the Flip-in
Date, because the Rights can be redeemed before the consummation of such
transaction.

     The foregoing description of the Rights is qualified in its entirety by
reference to the Rights Agreement and the exhibits thereto.


ITEM 2. EXHIBITS

     1.   Stockholder Protection Rights Agreement, dated as of February 21, 1995
          as filed as Exhibit 1 to Form 8-A filed by the Registrant on February
          27, 1995, is incorporated herein by reference.


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                                   SIGNATURES

     Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the Registrant has duly caused this registration statement to be signed
on its behalf by the undersigned, thereunto duly authorized.


                                          COMMUNITY BANK SYSTEM, INC.


                                          By: /s/ SANFORD A. BELDEN
                                              ----------------------------------
                                                  Sanford A. Belden
                                                  President and CEO


Dated:  December 9, 1997


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