As filed with the Securities and Exchange Commission on December 16, 1997.


                                                    Registration No. 333-


                      SECURITIES AND EXCHANGE COMMISSION
                           Washington, D.C. 20549

                                  FORM S-8

                           REGISTRATION STATEMENT
                      UNDER THE SECURITIES ACT OF 1933

                             F.N.B. CORPORATION
            (Exact name of registrant as specified in its charter)

      PENNSYLVANIA                                           25-1255406
      (State or other jurisdiction                           (I.R.S. Employer
      of incorporation or organization)                      Identification No.)

      ONE F.N.B. BOULEVARD
      HERMITAGE, PA                                           16148
      (Address of Principal                                   (zip code)
      Executive Offices)

                     STOCK OPTIONS ASSUMED IN ACQUISITION OF
                      MERCANTILE BANK OF SOUTHWEST FLORIDA
                              (Full Title of Plan)
                              ____________________

                                PETER MORTENSEN
                 CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER
                               F.N.B. CORPORATION
                              ONE F.N.B. BOULEVARD
                              HERMITAGE, PA  16148
                     (Name and address of agent for service)

                                (412) 981-6000
           (Telephone number, including area code, of agent for service)
                                ---------------

                         CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------
                                    Proposed      Proposed
                                    Maximum       Maximum  
                       Amount       Offering      Aggregate     Amount of 
Title of Securities     to be       Price Per     Offering     Registration
to be Registered      Registered    Share (1)     Price (2)        Fee
--------------------------------------------------------------------------------
Common Stock,
par value
$2.00 per share        34,444         $26.14      $595,616       $175.71
                       shares                             

 (1)      Maximum option exercise price of stock options with exercise prices
          in the range from $13.91 to $26.14.
 (2)      Calculated pursuant to rule 457(h) based on the option exercise 
          prices and number of shares issuable at each price.

<PAGE>

                                PART II
            INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
            --------------------------------------------------

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

        The following documents filed by the Corporation with the Securities 
and Exchange Commission (the "Commission") are incorporated by reference into
this Registration Statement: 

        1.  FNB's Annual Report on Form 10-K for the fiscal year ended 
            December 31, 1996;

        2.  FNB's Quarterly Report on Form 10-Q for the quarters ended 
            March 31, 1997, June 30, 1997 and September 30, 1997;

        3.  The Corporation's Current Reports Form 8-K filed January 24, 1997, 
            March 5, 1997, April 22, 1997 and July 22, 1997;

        4.  FNB's definitive Proxy Statement filed with the Commission pursuant
            to Section 14 of the Securities Exchange Act of 1934, as amended,
            (the "Exchange Act"), in connection with the Annual Meeting of 
            Shareholders of FNB held on April 23, 1997; and

        5.  The description of FNB's Common Stock, par value $2.00 per share 
            (the "Common Stock"), contained in FNB's Registration Statement 
            filed under Section 12 of the Exchange Act, including all amendments
            and reports updating such description. 

        All documents subsequently filed by FNB with the Commission pursuant 
to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act subsequent to the 
date of this Registration Statement and prior to the filing of a post-
effective amendment which indicates that all securities offered have been 
sold or which de-registers all securities then remaining unsold, shall be 
deemed to be incorporated in the Registration Statement and to be a part 
thereof from the date of filing of such document.

ITEM 4. DESCRIPTION OF SECURITIES.
       
        Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

        The consolidated financial statements of FNB at December 31, 1996  
and 1995, and for each of the three years in the period ended December 31, 1996,
have been audited by Ernst & Young LLP, independent auditors, as set forth in
their report thereon, included in FNB's Current Report on Form 8-K dated 
July 22, 1997 and incorporated herein by reference, which is based in part on
the reports of Hill, Barth & King, Inc., independent auditors who audited 
Southwest Banks, Inc., and Coopers & Lybrand L.L.P., independent auditors, 
who audited West Coast Bancorp, Inc.  The financial statements referred to 
above are incorporated herein by reference in reliance upon such reports 
given upon the authority of such firms as experts in accounting and auditing.

        The legality of the securities which are the subject of this 
registration statement will be passed upon by Cohen & Grigsby, P.C., 
Pittsburgh, Pennsylvania, counsel to FNB.

<PAGE>

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

        The effect of charter, by-law, statutory and other provisions whereby
the directors and officers of FNB may be insured or indemnified against 
liability as officers and directors are set out below:

        Article IX of the Bylaws of the Corporation provides that the 
Corporation shall indemnify each director and officer of the Corporation 
and of its controlled subsidiaries made or threatened to be made a party 
to any civil, criminal, administrative or investigative action, suit or 
proceeding (whether brought by or in the name of the Corporation or otherwise)
arising out of such director's or officer's service to the Corporation or to 
another organization at the Corporation's request against all expenses 
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by such director and officer in connection
with such action, suit or proceeding.  Indemnification shall not be made 
with respect to actions, suits or proceedings where the act or omission giving
rise to the claim for indemnification has been determined to have constituted
willful misconduct or recklessness or where prohibited by law.  In addition,
expenses incurred by each director and officer in defending any such action,
suit or proceeding, shall be paid by the Corporation in advance of the final 
disposition of such action, suit or proceeding if an undertaking (in form 
and scope satisfactory to the Corporation) shall have been furnished to the 
Corporation to repay amounts so advanced if and to the extent it shall 
ultimately be determined that such officer or director is not entitled to 
indemnification and certain other conditions shall have been satisfied. The 
Corporation may purchase and maintain insurance, create a fund of any nature,
grant a security interest or otherwise secure or insure in any manner its 
indemnification obligations.  

        Section 1741 of the Pennsylvania Business Corporation Law provides 
that a corporation shall (subject to the provisions described in the second
succeeding paragraph) have the power to indemnify any person who was or
is a party, or is threatened to be made a party, to any threatened, pending 
or completed action or proceeding, whether civil, criminal, administrative 
or investigative (other than an action by or in the right of the corporation),
by reason of the fact that such person is or was a representative of the 
corporation, or is or was serving at the request of the corporation as a 
representative of another domestic or foreign corporation for profit or 
not-for-profit, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in 
settlement actually and reasonably incurred by such person in connection 
with the action or proceeding if such person acted in good faith and in a 
manner he reasonably believed to be in, or not opposed to, the best interests
of the corporation and, with respect to any criminal proceeding, had no 
reasonable cause to believe his conduct was unlawful.  The termination of 
any action or proceeding by judgment, order, settlement or conviction, or 
upon a plea of nolo contendere or its equivalent shall not of itself create 
a presumption that such person did not act in good faith and in a manner 
which he reasonably believed to be in, or not opposed to, the best interests
of the corporation and, with respect to any criminal proceeding, had 
reasonable cause to believe that his conduct was unlawful.

        Section 1742 of the Pennsylvania Business Corporation Law provides 
that a corporation shall (subject to the provisions described in the 
succeeding paragraph) have the power to indemnify any person who was or is a
party, or is threatened to be made a party, to any threatened, pending or 
completed action by or in the right of the corporation to procure a judgment 
in its favor by reason of the fact that such person is or was a representative 
of the corporation, or is or was serving at the request of the corporation 
as a representative of another domestic or foreign corporation for profit or 
not-for-profit, partnership, joint venture, trust or other enterprise against 
expenses (including attorneys' fees) actually and reasonably incurred by such 
person in connection with the defense or settlement of the action if such 
person acted in good faith and in a manner he reasonably believed to be in, 
or not opposed to, the best interests of the corporation.  Indemnification 
shall not be made in respect of any claim, issue or matter as to which such 
person has been adjudged to be liable to the corporation unless and only to 
the extent that the court of common pleas of the county in which the 
registered office of the corporation is located or the court in which the 
action was brought determines upon application that, despite the adjudication 
of liability but in view of all the circumstances of the case, such person is 
fairly and reasonably entitled to indemnity for such expenses that the court 
of common pleas or other court deems proper.

        Under Section 1744 of the Pennsylvania Business Corporation Law, any 
such indemnification (unless ordered by a court) shall be made by the 
corporation only as authorized in the specific case upon a determination
that indemnification of the representative is proper in the circumstances 
because such person has met the applicable standard of conduct.  Such 
determination shall be made:

<PAGE>

        (1)  By the Board of Directors by a majority vote of a quorum 
             consisting of directors who were not parties to the action or 
             proceeding; or

        (2)  If such quorum is not obtainable or, even if obtainable a 
             majority vote of a quorum of disinterested directors so directs, 
             by independent legal counsel in a written opinion; or

        (3)  By the shareholders.

        Notwithstanding the above, Section 1743 provides that to the extent 
that a representative of the corporation has been successful on the merits or 
otherwise in defense of any action or proceeding referred to above, or in
defense of any claim, issue or matter therein, such person shall be 
indemnified against expenses (including attorneys' fees) actually and 
reasonably incurred by such person in connection therewith.

        Under Section 1745 of the Pennsylvania Business Corporation Law, 
expenses (including attorneys' fees) incurred in defending any action or 
proceeding may be paid by the corporation in advance of the final disposition
of the action or proceeding upon receipt of an undertaking by or on behalf of 
the representative to repay such amount if it is ultimately determined that 
such person is not entitled to be indemnified by the corporation.  

        Section 1746 of the Pennsylvania Business Corporation Law further 
provides that the indemnification provided by Sections 1741, 1742 and 1743 
and the advancement of expenses provided by Section 1745 shall not be deemed 
exclusive of any other rights to which a person seeking indemnification or 
advancement of expenses may be entitled under any bylaw, agreement, vote of 
shareholders, disinterested directors or otherwise, both as to action in his 
official capacity and as to action in another capacity while holding that 
office.  A corporation may create a fund of any nature, which may, but need 
not be, under the control of a trustee, or otherwise secure or insure in any
manner its indemnification obligations, whether arising under or pursuant to 
Section 1746 or otherwise. Indemnification pursuant to Section 1746 shall 
not be made in any case where the act or failure to act giving rise to the 
claim for indemnification is determined by a court to have constituted 
willful misconduct or recklessness.

        Indemnification pursuant to Section 1746 under any bylaw, agreement, 
vote of shareholders, or directors or otherwise may be granted for any action 
taken or any failure to take any action and may be made whether or not the 
corporation would have the power to indemnify the person under any other 
provision of law except as provided in such Section 1746 and whether or not 
the indemnified liability arises or arose from any threatened, pending or
completed action by or in the right of the corporation.  Section 1746 declares 
such indemnification to be consistent with the public policy of Pennsylvania.

        The foregoing is only a general summary of certain aspects of 
Pennsylvania law dealing with the indemnification of directors and officers 
and does not purport to be complete.  It is qualified in its entirety by
reference to the relevant statutes which contain detailed specific provisions 
regarding the circumstances under which and the person for whose benefit 
indemnification shall or may be made and accordingly are incorporated herein 
by reference.

<PAGE>

ITEM 8. EXHIBITS.

         5.1  Opinion of Cohen & Grigsby, P.C. regarding legality of the 
              securities 

        23.1  Consent of Ernst & Young LLP

        23.2  Consent of Hill, Barth & King, Inc.

        23.3  Consent of Coopers & Lybrand L.L.P.

        23.4  Consent of Cohen & Grigsby, P.C. (included in Exhibit 5.1)

        24    Power of Attorney (included on signature pages of this 
              Registration Statement)

ITEM 9. UNDERTAKINGS.

(a)     Rule 415 Offering undertaking:
         
        The undersigned registrant hereby undertakes:

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

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

             (ii)  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, represents a fundamental 
                   change in the information set forth in the Registration 
                   Statement;

             (iii) 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 paragraphs (a)(l)(i) and (a)(l)(ii) do not apply to the 
extent the information required to be included in a post-effective amendment 
by those paragraphs is contained in periodic reports filed by the Corporation
pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 
that are incorporated by reference in the Registration Statement.

        (2)  That, for the purpose of determining any liability under the 
             Securities Act of 1933, each 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.

<PAGE>

(b)     Filings Incorporating Subsequent Exchange Act Documents by Reference 
        undertaking:

        The undersigned registrant hereby undertakes that, for purposes of 
determining any liability under the Securities Act of 1933, each filing of 
the Corporation's annual report pursuant to Section 13(a) or Section 15(d) of
the Securities Exchange Act of 1934 (and, where applicable, each filing of 
an employee benefit plan's annual report pursuant to Section 15(d) of the 
Securities Exchange Act of 1934) that is incorporated by reference in the
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.

(c)     Filing of Registration Statement on Form S-8 undertaking:

        Insofar as indemnification for liabilities arising under the 
Securities Act of 1933 may be permitted to directors, officers and controlling 
persons of the registrant pursuant to the foregoing provisions or otherwise, 
the registrant has been advised that in the opinion of the Securities and 
Exchange Commission such indemnification is against public policy as expressed 
in the Act and is, therefore, unenforceable.  In the event that a claim for
indemnification against such liabilities (other than the payment by the 
registrant of expenses incurred or paid by a director, officer or controlling 
person of the registrant 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, the registrant 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 Act 
and will be governed by the final adjudication of such issue.

<PAGE>

                                 SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the 
Corporation 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 
registration statement to be signed on its behalf by the undersigned, 
thereunto duly authorized, in the City of Hermitage, Commonwealth of 
Pennsylvania, on December 16, 1997.  

                                         F.N.B. CORPORATION


                                         By /s/ Peter Mortensen                
                                         --------------------------------------
                                         Peter Mortensen, Chairman, President
                                         and Chief Executive Officer


                              POWER OF ATTORNEY

        KNOW ALL MEN BY THESE PRESENT, that each person whose signature appears 
below constitutes and appoints Peter Mortensen, John D. Waters and 
William J. Rundorff, and each of them, his true and lawful attorneys-in-fact 
and agents, with full power of substitution and resubstitution, for him and in 
his name, place and stead, in any and all capacities, to sign any and all 
amendments (including post-effective amendments) to this registration 
statement, and to file the same, with all exhibits thereto, and other 
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents, and each of them, full power 
and authority to do and perform each and every act and thing requisite and 
necessary to be done, as fully and to all intents and purposes as he might 
do in person, hereby ratifying and confirming all that said attorneys-in-
fact and agents or either of them, or their or his substitutes, may lawfully 
do or cause to be done by virtue thereof. 
        
        Pursuant to the requirements of the Securities Act of 1933, this 
registration statement has been signed by the following persons in the 
capacities and on the dates indicated.  


/s/ Peter Mortensen           Chairman, President, Chief      December 16, 1997
--------------------------    Executive Officer and Director  
Peter Mortensen               (Principal Executive Officer)

                                                                     
/s/ Stephen J. Gurgovits      Executive Vice President        December 16, 1997
--------------------------    and Director
Stephen J. Gurgovits                                                  


/s/ Gary L. Tice              Chief Operating Officer         December 16, 1997
--------------------------    Executive Vice President
Gary L. Tice                  and Director                        


/s/ William J. Rundorff       Executive Vice President        December 16, 1997
-------------------------
William J. Rundorff


/s/ John D. Waters            Vice President and CFO          December 16, 1997
-------------------------     (Pricipal Financial and 
John D. Waters                Accounting Officer)


/s/ W. Richard Blackwood      Director                        December 16, 1997
-------------------------
W. Richard Blackwood


<PAGE>

/s/ William B. Campbell       Director                        December 16, 1997
-------------------------
William B. Campbell


/s/ Charles T. Cricks         Director                        December 16, 1997
-------------------------
Charles T. Cricks


/s/ Henry M. Ekker            Director                        December 16, 1997
-------------------------
Henry M. Ekker


/s/ Thomas C. Elliot          Director                        December 16, 1997
-------------------------
Thomas C. Elliott


/s/ Thomas W. Hodge           Director                        December 16, 1997
-------------------------
Thomas W. Hodge


/s/ James S. Lindsey          Director                        December 16, 1997
-------------------------
James S. Lindsey


/s/ Paul P. Lynch             Director                        December 16, 1997
-------------------------
Paul P. Lynch


/s/ Edward J. Mace            Director                        December 16, 1997
-------------------------
Edward J. Mace

                                                            
/s/ Robert S. Moss            Director                        December 16, 1997
-------------------------
Robert S. Moss

                   
/s/ Richard C. Myers          Director                        December 16, 1997
-------------------------
Richard C. Myers


/s/ John R. Perkins           Director                        December 16, 1997
-------------------------
John R. Perkins


/s/ William A. Quinn          Director                        December 16, 1997
-------------------------
William A. Quinn


/s/ George A. Seeds, Jr.      Director                        December 16, 1997
-------------------------
George A. Seeds, Jr.

<PAGE>

/s/ William J. Strimbu        Director                        December 16, 1997
-------------------------
William J. Strimbu


/s/ Archie O. Wallace         Director                        December 16, 1997
-------------------------
Archie O. Wallace


/s/ Joseph M. Walton          Director                        December 16, 1997
-------------------------
Joseph M. Walton


/s/ James T. Weller           Director                        December 16, 1997
-------------------------
James T. Weller 


/s/ Eric J. Werner            Director                        December 16, 1997
-------------------------
Eric J. Werner


/s/ R. Benjamin Wiley         Director                        December 16, 1997
-------------------------
R. Benjamin Wiley


/s/ Donna C. Winner           Director                        December 16, 1997
-------------------------
Donna C. Winner

<PAGE>

                               EXHIBIT INDEX
 

         5.1       Opinion of Cohen & Grigsby, P.C. regarding 
                   legality of the securities 

        23.1       Consent of Ernst & Young LLP

        23.2       Consent of Hill, Barth & King, Inc.

        23.3       Consent of Coopers & Lybrand L.L.P.

        23.4       Consent of Cohen & Grigsby, P.C. (included in Exhibit 5.1)

<PAGE>

                                                                 Exhibit 5.1

                     OPINION OF COHEN & GRIGSBY, P.C.



December 15, 1997

F.N.B. Corporation
One F.N.B. Boulevard
Hermitage, PA 16148

Gentlemen:

     We refer to the Form S-8 Registration Statement under the Securities Act of
1933 to be filed by F.N.B. Corporation ("FNB") with the Securities and 
Exchange Commission on or about December 16, 1997, relating to the issuance and 
sale of up to 34,444 shares of its Common Stock to be issued under that certain
stock option plan assumed by FNB in the acquisition of Mercantile Bank of 
Southwest Florida (the "Assumed Stock Options").  We have acted as counsel to 
FNB in connection with the preparation and filing of such Registration 
Statement, and have examined such records, certificates and documents as we 
deemed relevant and necessary as a basis for the opinion set forth below. 

     Based upon the foregoing, we are of the opinion that the shares of Common 
Stock to be issued, when issued upon exercise of an Assumed Stock Option and 
upon payment of the consideration therefor,  will be validly issued, fully-paid 
and non-assessable shares of Common Stock of FNB. 

     We consent to the inclusion of this opinion as an exhibit to the 
Registration Statement and to the reference to our firm in Part II of the 
Registration Statement.

     This Opinion Letter is governed by , and shall be interpreted in accordance
with, the Legal Opinion Accord (the "Accord") of the ABA Section of Business 
Law (1991) as supplemented or modified by Part I, together with the Forward 
and Glossary of the Pennsylvania third Party Legal Opinion Supplement (the 
"Pennsylvania Supplement") of the PBA Section of Corporation, Banking and 
Business Law (1992).  As a consequence, it is subject to a number of 
qualifications, exceptions, definitions, limitations on coverage and other 
limitations, all as more particularly described in the Accord and the 
Pennsylvania Supplement, and this Opinion Letter should be read in conjunction
therewith.  Unless otherwise indicated, capitalized terms used in this Opinion 
that are defined in the Accord or the Pennsylvania Supplement will have the 
same meanings in this Opinion as the meanings set forth in the Accord or
the Pennsylvania Supplement, respectively (and, to the extent of a conflict 
between the same, priority shall be given to the Accord and the Pennsylvania 
Supplement in that order).

                                         Yours truly,


                                         /s/ COHEN & GRIGSBY, P.C.
                                         COHEN & GRIGSBY, P.C.


<PAGE>

                                                                 EXHIBIT 23.1




            CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS


We consent to the reference to our firm under the caption "Experts" in this 
Registration Statement (Form S-8) of F.N.B. Corporation for the registration 
of 34,444 shares of its common stock and to the incorporation by reference
therein of our report dated July 3, 1997 with respect to the consolidated 
financial statements of F.N.B. Corporation included in its Current Report 
on Form 8-K dated July 22, 1997 filed with the Securities and Exchange 
Commission.



                                          /s/ ERNST & YOUNG LLP
                                          ERNST & YOUNG, LLP


Pittsburgh, Pennsylvania
December 11, 1997

<PAGE>

                                                                 EXHIBIT 23.2


             CONSENT OF HILL, BARTH & KING, INC., INDEPENDENT AUDITORS


We consent to the reference to our firm under the caption "Experts" in this 
Registration Statement and related Prospectus of F.N.B. Corporation on 
Form S-8 and to the incorporation by reference therein of our report dated
January 22 , 1997 relating to the consolidated financial statements of Southwest
Banks, Inc. which have been incorporated into the consolidated financial 
statements of F.N.B. Corporation and Subsidiaries for the year ended 
December 31, 1996 by reference in the Current Report on Form 8-K dated 
July 22, 1997.





                                         /s/ HILL, BARTH & KING, INC.
                                        HILL, BARTH & KING, INC.   
                                        Certified Public Accountants


Naples, Florida
December 12, 1997

<PAGE>

                                                                 EXHIBIT 23.3




                    CONSENT OF INDEPENDENT ACCOUNTANTS



We consent to the incorporation by reference in this Registration Statement on 
Form S-8 of our reports dated January 24, 1997 and January 19, 1996 included 
as Exhibits 99.3 and 99.4, respectively, to F.N.B. Corporation's Form 8-K 
filed July 22, 1997, with respect to our audits of the consolidated financial 
statements of West Coast Bancorp, Inc. for the years ended December 31, 1996 
and 1995 and the year ended December 31, 1994, respectively.  We also consent
to the reference to our firm under the caption "Interests of Named Experts and 
Counsel."




                                         /s/ Coopers & Lybrand L.L.P
                                         COOPERS & LYBRAND L.L.P.

Tampa, Florida
December 15, 1997
[{"type": "S-8", "sequence": "1", "secsgml_size_bytes": 30684}]
{"company-data": {"conformed-name": "FNB CORP/PA", "cik": "0000037808", "assigned-sic": "6021", "irs-number": "251255406", "state-of-incorporation": "PA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-42333", "film-number": "97738947"}, "business-address": {"street1": "HERMITAGE SQUARE", "city": "HERMITAGE", "state": "PA", "zip": "16148", "phone": "4129816000"}, "mail-address": {"street1": "HERMITAGE SQUARE", "city": "HERMITAGE", "state": "PA", "zip": "16148"}, "former-company": {"former-conformed-name": "CITIZENS BUDGET CO", "date-changed": "19750909"}}
As filed with the Securities and Exchange Commission on December 16, 1997.

                                                    Registration No. 333-

                      SECURITIES AND EXCHANGE COMMISSION
                           Washington, D.C. 20549

                                  FORM S-8

                           REGISTRATION STATEMENT
                      UNDER THE SECURITIES ACT OF 1933

                             F.N.B. CORPORATION
            (Exact name of registrant as specified in its charter)

      PENNSYLVANIA                                           25-1255406
      (State or other jurisdiction                           (I.R.S. Employer
      of incorporation or organization)                      Identification No.)

      ONE F.N.B. BOULEVARD
      HERMITAGE, PA                                           16148
      (Address of Principal                                   (zip code)
      Executive Offices)

                     STOCK OPTIONS ASSUMED IN ACQUISITION OF
                      MERCANTILE BANK OF SOUTHWEST FLORIDA
                              (Full Title of Plan)
                              ____________________

                                PETER MORTENSEN
                 CHAIRMAN, PRESIDENT AND CHIEF EXECUTIVE OFFICER
                               F.N.B. CORPORATION
                              ONE F.N.B. BOULEVARD
                              HERMITAGE, PA  16148
                     (Name and address of agent for service)

                                (412) 981-6000
           (Telephone number, including area code, of agent for service)
                                ---------------

                         CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------
                                    Proposed      Proposed
                                    Maximum       Maximum  
                       Amount       Offering      Aggregate     Amount of 
Title of Securities     to be       Price Per     Offering     Registration
to be Registered      Registered    Share (1)     Price (2)        Fee
--------------------------------------------------------------------------------
Common Stock,
par value
$2.00 per share        34,444         $26.14      $595,616       $175.71
                       shares                             

 (1)      Maximum option exercise price of stock options with exercise prices
          in the range from $13.91 to $26.14.
 (2)      Calculated pursuant to rule 457(h) based on the option exercise 
          prices and number of shares issuable at each price.
PART II
            INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
            --------------------------------------------------

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE.

        The following documents filed by the Corporation with the Securities 
and Exchange Commission (the "Commission") are incorporated by reference into
this Registration Statement: 

        1.  FNB's Annual Report on Form 10-K for the fiscal year ended 
            December 31, 1996;

        2.  FNB's Quarterly Report on Form 10-Q for the quarters ended 
            March 31, 1997, June 30, 1997 and September 30, 1997;

        3.  The Corporation's Current Reports Form 8-K filed January 24, 1997, 
            March 5, 1997, April 22, 1997 and July 22, 1997;

        4.  FNB's definitive Proxy Statement filed with the Commission pursuant
            to Section 14 of the Securities Exchange Act of 1934, as amended,
            (the "Exchange Act"), in connection with the Annual Meeting of 
            Shareholders of FNB held on April 23, 1997; and

        5.  The description of FNB's Common Stock, par value $2.00 per share 
            (the "Common Stock"), contained in FNB's Registration Statement 
            filed under Section 12 of the Exchange Act, including all amendments
            and reports updating such description. 

        All documents subsequently filed by FNB with the Commission pursuant 
to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act subsequent to the 
date of this Registration Statement and prior to the filing of a post-
effective amendment which indicates that all securities offered have been 
sold or which de-registers all securities then remaining unsold, shall be 
deemed to be incorporated in the Registration Statement and to be a part 
thereof from the date of filing of such document.

ITEM 4. DESCRIPTION OF SECURITIES.
       
        Not applicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL.

        The consolidated financial statements of FNB at December 31, 1996  
and 1995, and for each of the three years in the period ended December 31, 1996,
have been audited by Ernst & Young LLP, independent auditors, as set forth in
their report thereon, included in FNB's Current Report on Form 8-K dated 
July 22, 1997 and incorporated herein by reference, which is based in part on
the reports of Hill, Barth & King, Inc., independent auditors who audited 
Southwest Banks, Inc., and Coopers & Lybrand L.L.P., independent auditors, 
who audited West Coast Bancorp, Inc.  The financial statements referred to 
above are incorporated herein by reference in reliance upon such reports 
given upon the authority of such firms as experts in accounting and auditing.

        The legality of the securities which are the subject of this 
registration statement will be passed upon by Cohen & Grigsby, P.C., 
Pittsburgh, Pennsylvania, counsel to FNB.
ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS.

        The effect of charter, by-law, statutory and other provisions whereby
the directors and officers of FNB may be insured or indemnified against 
liability as officers and directors are set out below:

        Article IX of the Bylaws of the Corporation provides that the 
Corporation shall indemnify each director and officer of the Corporation 
and of its controlled subsidiaries made or threatened to be made a party 
to any civil, criminal, administrative or investigative action, suit or 
proceeding (whether brought by or in the name of the Corporation or otherwise)
arising out of such director's or officer's service to the Corporation or to 
another organization at the Corporation's request against all expenses 
(including attorneys' fees), judgments, fines and amounts paid in settlement
actually and reasonably incurred by such director and officer in connection
with such action, suit or proceeding.  Indemnification shall not be made 
with respect to actions, suits or proceedings where the act or omission giving
rise to the claim for indemnification has been determined to have constituted
willful misconduct or recklessness or where prohibited by law.  In addition,
expenses incurred by each director and officer in defending any such action,
suit or proceeding, shall be paid by the Corporation in advance of the final 
disposition of such action, suit or proceeding if an undertaking (in form 
and scope satisfactory to the Corporation) shall have been furnished to the 
Corporation to repay amounts so advanced if and to the extent it shall 
ultimately be determined that such officer or director is not entitled to 
indemnification and certain other conditions shall have been satisfied. The 
Corporation may purchase and maintain insurance, create a fund of any nature,
grant a security interest or otherwise secure or insure in any manner its 
indemnification obligations.  

        Section 1741 of the Pennsylvania Business Corporation Law provides 
that a corporation shall (subject to the provisions described in the second
succeeding paragraph) have the power to indemnify any person who was or
is a party, or is threatened to be made a party, to any threatened, pending 
or completed action or proceeding, whether civil, criminal, administrative 
or investigative (other than an action by or in the right of the corporation),
by reason of the fact that such person is or was a representative of the 
corporation, or is or was serving at the request of the corporation as a 
representative of another domestic or foreign corporation for profit or 
not-for-profit, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in 
settlement actually and reasonably incurred by such person in connection 
with the action or proceeding if such person acted in good faith and in a 
manner he reasonably believed to be in, or not opposed to, the best interests
of the corporation and, with respect to any criminal proceeding, had no 
reasonable cause to believe his conduct was unlawful.  The termination of 
any action or proceeding by judgment, order, settlement or conviction, or 
upon a plea of nolo contendere or its equivalent shall not of itself create 
a presumption that such person did not act in good faith and in a manner 
which he reasonably believed to be in, or not opposed to, the best interests
of the corporation and, with respect to any criminal proceeding, had 
reasonable cause to believe that his conduct was unlawful.

        Section 1742 of the Pennsylvania Business Corporation Law provides 
that a corporation shall (subject to the provisions described in the 
succeeding paragraph) have the power to indemnify any person who was or is a
party, or is threatened to be made a party, to any threatened, pending or 
completed action by or in the right of the corporation to procure a judgment 
in its favor by reason of the fact that such person is or was a representative 
of the corporation, or is or was serving at the request of the corporation 
as a representative of another domestic or foreign corporation for profit or 
not-for-profit, partnership, joint venture, trust or other enterprise against 
expenses (including attorneys' fees) actually and reasonably incurred by such 
person in connection with the defense or settlement of the action if such 
person acted in good faith and in a manner he reasonably believed to be in, 
or not opposed to, the best interests of the corporation.  Indemnification 
shall not be made in respect of any claim, issue or matter as to which such 
person has been adjudged to be liable to the corporation unless and only to 
the extent that the court of common pleas of the county in which the 
registered office of the corporation is located or the court in which the 
action was brought determines upon application that, despite the adjudication 
of liability but in view of all the circumstances of the case, such person is 
fairly and reasonably entitled to indemnity for such expenses that the court 
of common pleas or other court deems proper.

        Under Section 1744 of the Pennsylvania Business Corporation Law, any 
such indemnification (unless ordered by a court) shall be made by the 
corporation only as authorized in the specific case upon a determination
that indemnification of the representative is proper in the circumstances 
because such person has met the applicable standard of conduct.  Such 
determination shall be made:
(1)  By the Board of Directors by a majority vote of a quorum 
             consisting of directors who were not parties to the action or 
             proceeding; or

        (2)  If such quorum is not obtainable or, even if obtainable a 
             majority vote of a quorum of disinterested directors so directs, 
             by independent legal counsel in a written opinion; or

        (3)  By the shareholders.

        Notwithstanding the above, Section 1743 provides that to the extent 
that a representative of the corporation has been successful on the merits or 
otherwise in defense of any action or proceeding referred to above, or in
defense of any claim, issue or matter therein, such person shall be 
indemnified against expenses (including attorneys' fees) actually and 
reasonably incurred by such person in connection therewith.

        Under Section 1745 of the Pennsylvania Business Corporation Law, 
expenses (including attorneys' fees) incurred in defending any action or 
proceeding may be paid by the corporation in advance of the final disposition
of the action or proceeding upon receipt of an undertaking by or on behalf of 
the representative to repay such amount if it is ultimately determined that 
such person is not entitled to be indemnified by the corporation.  

        Section 1746 of the Pennsylvania Business Corporation Law further 
provides that the indemnification provided by Sections 1741, 1742 and 1743 
and the advancement of expenses provided by Section 1745 shall not be deemed 
exclusive of any other rights to which a person seeking indemnification or 
advancement of expenses may be entitled under any bylaw, agreement, vote of 
shareholders, disinterested directors or otherwise, both as to action in his 
official capacity and as to action in another capacity while holding that 
office.  A corporation may create a fund of any nature, which may, but need 
not be, under the control of a trustee, or otherwise secure or insure in any
manner its indemnification obligations, whether arising under or pursuant to 
Section 1746 or otherwise. Indemnification pursuant to Section 1746 shall 
not be made in any case where the act or failure to act giving rise to the 
claim for indemnification is determined by a court to have constituted 
willful misconduct or recklessness.

        Indemnification pursuant to Section 1746 under any bylaw, agreement, 
vote of shareholders, or directors or otherwise may be granted for any action 
taken or any failure to take any action and may be made whether or not the 
corporation would have the power to indemnify the person under any other 
provision of law except as provided in such Section 1746 and whether or not 
the indemnified liability arises or arose from any threatened, pending or
completed action by or in the right of the corporation.  Section 1746 declares 
such indemnification to be consistent with the public policy of Pennsylvania.

        The foregoing is only a general summary of certain aspects of 
Pennsylvania law dealing with the indemnification of directors and officers 
and does not purport to be complete.  It is qualified in its entirety by
reference to the relevant statutes which contain detailed specific provisions 
regarding the circumstances under which and the person for whose benefit 
indemnification shall or may be made and accordingly are incorporated herein 
by reference.
ITEM 8. EXHIBITS.

         5.1  Opinion of Cohen & Grigsby, P.C. regarding legality of the 
              securities 

        23.1  Consent of Ernst & Young LLP

        23.2  Consent of Hill, Barth & King, Inc.

        23.3  Consent of Coopers & Lybrand L.L.P.

        23.4  Consent of Cohen & Grigsby, P.C. (included in Exhibit 5.1)

        24    Power of Attorney (included on signature pages of this 
              Registration Statement)

ITEM 9. UNDERTAKINGS.

(a)     Rule 415 Offering undertaking:
         
        The undersigned registrant hereby undertakes:

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

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

             (ii)  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, represents a fundamental 
                   change in the information set forth in the Registration 
                   Statement;

             (iii) 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 paragraphs (a)(l)(i) and (a)(l)(ii) do not apply to the 
extent the information required to be included in a post-effective amendment 
by those paragraphs is contained in periodic reports filed by the Corporation
pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 
that are incorporated by reference in the Registration Statement.

        (2)  That, for the purpose of determining any liability under the 
             Securities Act of 1933, each 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.
(b)     Filings Incorporating Subsequent Exchange Act Documents by Reference 
        undertaking:

        The undersigned registrant hereby undertakes that, for purposes of 
determining any liability under the Securities Act of 1933, each filing of 
the Corporation's annual report pursuant to Section 13(a) or Section 15(d) of
the Securities Exchange Act of 1934 (and, where applicable, each filing of 
an employee benefit plan's annual report pursuant to Section 15(d) of the 
Securities Exchange Act of 1934) that is incorporated by reference in the
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.

(c)     Filing of Registration Statement on Form S-8 undertaking:

        Insofar as indemnification for liabilities arising under the 
Securities Act of 1933 may be permitted to directors, officers and controlling 
persons of the registrant pursuant to the foregoing provisions or otherwise, 
the registrant has been advised that in the opinion of the Securities and 
Exchange Commission such indemnification is against public policy as expressed 
in the Act and is, therefore, unenforceable.  In the event that a claim for
indemnification against such liabilities (other than the payment by the 
registrant of expenses incurred or paid by a director, officer or controlling 
person of the registrant 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, the registrant 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 Act 
and will be governed by the final adjudication of such issue.
SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the 
Corporation 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 
registration statement to be signed on its behalf by the undersigned, 
thereunto duly authorized, in the City of Hermitage, Commonwealth of 
Pennsylvania, on December 16, 1997.  

                                         F.N.B. CORPORATION

                                         By /s/ Peter Mortensen                
                                         --------------------------------------
                                         Peter Mortensen, Chairman, President
                                         and Chief Executive Officer

                              POWER OF ATTORNEY

        KNOW ALL MEN BY THESE PRESENT, that each person whose signature appears 
below constitutes and appoints Peter Mortensen, John D. Waters and 
William J. Rundorff, and each of them, his true and lawful attorneys-in-fact 
and agents, with full power of substitution and resubstitution, for him and in 
his name, place and stead, in any and all capacities, to sign any and all 
amendments (including post-effective amendments) to this registration 
statement, and to file the same, with all exhibits thereto, and other 
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorneys-in-fact and agents, and each of them, full power 
and authority to do and perform each and every act and thing requisite and 
necessary to be done, as fully and to all intents and purposes as he might 
do in person, hereby ratifying and confirming all that said attorneys-in-
fact and agents or either of them, or their or his substitutes, may lawfully 
do or cause to be done by virtue thereof. 
        
        Pursuant to the requirements of the Securities Act of 1933, this 
registration statement has been signed by the following persons in the 
capacities and on the dates indicated.  

/s/ Peter Mortensen           Chairman, President, Chief      December 16, 1997
--------------------------    Executive Officer and Director  
Peter Mortensen               (Principal Executive Officer)

                                                                     
/s/ Stephen J. Gurgovits      Executive Vice President        December 16, 1997
--------------------------    and Director
Stephen J. Gurgovits                                                  

/s/ Gary L. Tice              Chief Operating Officer         December 16, 1997
--------------------------    Executive Vice President
Gary L. Tice                  and Director                        

/s/ William J. Rundorff       Executive Vice President        December 16, 1997
-------------------------
William J. Rundorff

/s/ John D. Waters            Vice President and CFO          December 16, 1997
-------------------------     (Pricipal Financial and 
John D. Waters                Accounting Officer)

/s/ W. Richard Blackwood      Director                        December 16, 1997
-------------------------
W. Richard Blackwood
/s/ William B. Campbell       Director                        December 16, 1997
-------------------------
William B. Campbell

/s/ Charles T. Cricks         Director                        December 16, 1997
-------------------------
Charles T. Cricks

/s/ Henry M. Ekker            Director                        December 16, 1997
-------------------------
Henry M. Ekker

/s/ Thomas C. Elliot          Director                        December 16, 1997
-------------------------
Thomas C. Elliott

/s/ Thomas W. Hodge           Director                        December 16, 1997
-------------------------
Thomas W. Hodge

/s/ James S. Lindsey          Director                        December 16, 1997
-------------------------
James S. Lindsey

/s/ Paul P. Lynch             Director                        December 16, 1997
-------------------------
Paul P. Lynch

/s/ Edward J. Mace            Director                        December 16, 1997
-------------------------
Edward J. Mace

                                                            
/s/ Robert S. Moss            Director                        December 16, 1997
-------------------------
Robert S. Moss

                   
/s/ Richard C. Myers          Director                        December 16, 1997
-------------------------
Richard C. Myers

/s/ John R. Perkins           Director                        December 16, 1997
-------------------------
John R. Perkins

/s/ William A. Quinn          Director                        December 16, 1997
-------------------------
William A. Quinn

/s/ George A. Seeds, Jr.      Director                        December 16, 1997
-------------------------
George A. Seeds, Jr.
/s/ William J. Strimbu        Director                        December 16, 1997
-------------------------
William J. Strimbu

/s/ Archie O. Wallace         Director                        December 16, 1997
-------------------------
Archie O. Wallace

/s/ Joseph M. Walton          Director                        December 16, 1997
-------------------------
Joseph M. Walton

/s/ James T. Weller           Director                        December 16, 1997
-------------------------
James T. Weller 

/s/ Eric J. Werner            Director                        December 16, 1997
-------------------------
Eric J. Werner

/s/ R. Benjamin Wiley         Director                        December 16, 1997
-------------------------
R. Benjamin Wiley

/s/ Donna C. Winner           Director                        December 16, 1997
-------------------------
Donna C. Winner
EXHIBIT INDEX
 

         5.1       Opinion of Cohen & Grigsby, P.C. regarding 
                   legality of the securities 

        23.1       Consent of Ernst & Young LLP

        23.2       Consent of Hill, Barth & King, Inc.

        23.3       Consent of Coopers & Lybrand L.L.P.

        23.4       Consent of Cohen & Grigsby, P.C. (included in Exhibit 5.1)
Exhibit 5.1

                     OPINION OF COHEN & GRIGSBY, P.C.

December 15, 1997

F.N.B. Corporation
One F.N.B. Boulevard
Hermitage, PA 16148

Gentlemen:

     We refer to the Form S-8 Registration Statement under the Securities Act of
1933 to be filed by F.N.B. Corporation ("FNB") with the Securities and 
Exchange Commission on or about December 16, 1997, relating to the issuance and 
sale of up to 34,444 shares of its Common Stock to be issued under that certain
stock option plan assumed by FNB in the acquisition of Mercantile Bank of 
Southwest Florida (the "Assumed Stock Options").  We have acted as counsel to 
FNB in connection with the preparation and filing of such Registration 
Statement, and have examined such records, certificates and documents as we 
deemed relevant and necessary as a basis for the opinion set forth below. 

     Based upon the foregoing, we are of the opinion that the shares of Common 
Stock to be issued, when issued upon exercise of an Assumed Stock Option and 
upon payment of the consideration therefor,  will be validly issued, fully-paid 
and non-assessable shares of Common Stock of FNB. 

     We consent to the inclusion of this opinion as an exhibit to the 
Registration Statement and to the reference to our firm in Part II of the 
Registration Statement.

     This Opinion Letter is governed by , and shall be interpreted in accordance
with, the Legal Opinion Accord (the "Accord") of the ABA Section of Business 
Law (1991) as supplemented or modified by Part I, together with the Forward 
and Glossary of the Pennsylvania third Party Legal Opinion Supplement (the 
"Pennsylvania Supplement") of the PBA Section of Corporation, Banking and 
Business Law (1992).  As a consequence, it is subject to a number of 
qualifications, exceptions, definitions, limitations on coverage and other 
limitations, all as more particularly described in the Accord and the 
Pennsylvania Supplement, and this Opinion Letter should be read in conjunction
therewith.  Unless otherwise indicated, capitalized terms used in this Opinion 
that are defined in the Accord or the Pennsylvania Supplement will have the 
same meanings in this Opinion as the meanings set forth in the Accord or
the Pennsylvania Supplement, respectively (and, to the extent of a conflict 
between the same, priority shall be given to the Accord and the Pennsylvania 
Supplement in that order).

                                         Yours truly,

                                         /s/ COHEN & GRIGSBY, P.C.
                                         COHEN & GRIGSBY, P.C.
EXHIBIT 23.1

            CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

We consent to the reference to our firm under the caption "Experts" in this 
Registration Statement (Form S-8) of F.N.B. Corporation for the registration 
of 34,444 shares of its common stock and to the incorporation by reference
therein of our report dated July 3, 1997 with respect to the consolidated 
financial statements of F.N.B. Corporation included in its Current Report 
on Form 8-K dated July 22, 1997 filed with the Securities and Exchange 
Commission.

                                          /s/ ERNST & YOUNG LLP
                                          ERNST & YOUNG, LLP

Pittsburgh, Pennsylvania
December 11, 1997
EXHIBIT 23.2

             CONSENT OF HILL, BARTH & KING, INC., INDEPENDENT AUDITORS

We consent to the reference to our firm under the caption "Experts" in this 
Registration Statement and related Prospectus of F.N.B. Corporation on 
Form S-8 and to the incorporation by reference therein of our report dated
January 22 , 1997 relating to the consolidated financial statements of Southwest
Banks, Inc. which have been incorporated into the consolidated financial 
statements of F.N.B. Corporation and Subsidiaries for the year ended 
December 31, 1996 by reference in the Current Report on Form 8-K dated 
July 22, 1997.

                                         /s/ HILL, BARTH & KING, INC.
                                        HILL, BARTH & KING, INC.   
                                        Certified Public Accountants

Naples, Florida
December 12, 1997
EXHIBIT 23.3

                    CONSENT OF INDEPENDENT ACCOUNTANTS

We consent to the incorporation by reference in this Registration Statement on 
Form S-8 of our reports dated January 24, 1997 and January 19, 1996 included 
as Exhibits 99.3 and 99.4, respectively, to F.N.B. Corporation's Form 8-K 
filed July 22, 1997, with respect to our audits of the consolidated financial 
statements of West Coast Bancorp, Inc. for the years ended December 31, 1996 
and 1995 and the year ended December 31, 1994, respectively.  We also consent
to the reference to our firm under the caption "Interests of Named Experts and 
Counsel."

                                         /s/ Coopers & Lybrand L.L.P
                                         COOPERS & LYBRAND L.L.P.

Tampa, Florida
December 15, 1997