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                                                                     EXHIBIT 8.1

                     [LETTERHEAD OF IGLER & DOUGHERTY, P.A.]


                               February 22, 2001



Board of Directors
Citizens Community Bancorp, Inc.
650 East Elkcam Circle
Marco Island, Florida  34145

Board of Directors
F.N.B. Corporation
One F.N.B. Boulevard
Hermitage, Pennsylvania 15148


Members of the Boards of Directors:


         You have requested our opinion concerning certain federal income tax
consequences of the proposed merger (the "Merger") of Citizens Community
Bancorp, Inc. ("CCBI") with and into F.N.B. Corporation ("FNB"), pursuant to the
terms of that certain Agreement and Plan of Merger by and among FNB, CCBI and
Citizens Community Bank of Florida (the "Merger Agreement") dated as of December
18, 2000, as described in the FNB Registration Statement on Form S-4, filed with
the Securities and Exchange Commission on or about February 6, 2001 (the
"Registration Statement").



         For purposes of rendering our opinion herein, we have conducted an
examination of the Internal Revenue Code of 1986, as amended (the "Code"), and
such other applicable federal laws, regulations, rulings, decisions, documents
and records as we have deemed necessary. With respect to factual matters, we
have relied upon the Merger Agreement, including, without limitation, the
representations of the parties set forth therein, and upon certain statements
and representations made to us in certificates by officers of CCBI and FNB, in
each case without independent verification thereof. With the consent of CCBI and
FNB, we have relied on the accuracy and completeness of the statements and
representations contained in such certificates and have assumed that such
certificates will be complete and accurate as of the effective time of the
Merger. We have also relied on the accuracy and completeness of the Registration
Statement and Proxy Statement/Prospectus of CCBI and FNB ("Proxy
Statement/Prospectus"). In addition, for purposes of this opinion, we have
assumed that at least fifty percent of the outstanding shares of CCBI common
stock (exclusive of any shares that may be acquired by FNB by exercising its
rights under that certain Stock Option Agreement by and between FNB and CCBI,
dated December 18, 2000) will be exchanged for FNB common stock in the Merger
and that the shares of CCBI common stock constitute capital assets in the hands
of each holder thereof.


         Based on the foregoing, and subject to the qualifications set forth
below, we are of the opinion that, under the Code:

         (1)      the Merger will constitute a reorganization within the meaning
                  of Section 368(a) of the Code;


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February 22, 2001
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         (2)      no gain or loss will be recognized by the shareholders of CCBI
                  on the exchange of their CCBI common stock for FNB common
                  stock pursuant to the terms of the Merger Agreement;

         (3)      the federal income tax basis of the FNB common stock for which
                  shares of CCBI common stock are exchanged pursuant to the
                  Merger Agreement will be the same as the basis of such shares
                  of CCBI common stock exchanged therefor (including basis
                  allocable to any fractional interest in any share of FNB
                  common stock);

         (4)      the holding period of FNB common stock for which shares of
                  CCBI common stock are exchanged will include the period that
                  such shares of CCBI common stock were held by the holder,
                  provided that such shares were capital assets of the holder;
                  and

         (5)      the receipt of cash in lieu of fractional shares will be
                  treated as if the fractional shares were distributed as part
                  of the exchange and then redeemed by FNB, and gain or loss
                  will be recognized in an amount equal to the difference
                  between the cash received and the basis of the fractional
                  share of FNB common stock surrendered, which gain or loss will
                  be a capital gain or loss if the CCBI common stock was a
                  capital asset in the hands of the shareholder.

         No opinion is expressed with respect to any of the following:

         (i)      The appropriate method to determine the fair market value of
                  any stock or other consideration received in any sale or
                  exchange;

         (ii)     The state, local or foreign tax consequences of any aspect of
                  the Merger; or

         (iii)    The federal income tax consequences of any aspect of the
                  Merger to holders of CCBI common stock who are subject to
                  special tax treatment for federal income tax purposes,
                  including among others, life insurance companies, tax exempt
                  entities and foreign taxpayers, or to holders of warrants or
                  options to purchase CCBI common stock, if any, which are
                  exchanged for or converted into options or warrants to acquire
                  FNB common stock.

         The opinions expressed herein are based upon our interpretation of
existing legal authorities, and no assurance can be given that such
interpretations would be followed if the exchange of shares contemplated by the
Merger became the subject of administrative or judicial proceedings. Statements
of opinion herein are opinions only and should not be interpreted as guarantees
of the current status of the law, nor should they be accepted as a guarantee
that a court of law or administrative agency will concur in such statement.

         We are licensed to practice law only in the State of Florida. We
express no opinion as to the law of any jurisdiction other than the laws of the
State of Florida and of the United States of America. We assume no obligation to
advise you of any events that occur subsequent to the date of this opinion.
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Citizens Community Bancorp, Inc.
February 22, 2001
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         This opinion is provided solely to CCBI and FNB for the purpose of
complying with the Merger Agreement and may not be relied upon or quoted in
whole or in part or otherwise referred to in any report or documents or
furnished to any person or entity, other than CCBI and FNB. Notwithstanding the
foregoing sentence, we expressly consent to the references to this opinion in
the Registration Statement and the Proxy Statement/Prospectus. In giving this
opinion, we do not hereby admit that we are in the category of persons whose
consent is required under Section 7 of the Securities Act of 1933, as amended.


                                                 Sincerely,

                                                 /s/ IGLER & DOUGHERTY, P.A.
                                                 ------------------------------
                                                     IGLER & DOUGHERTY, P.A.