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                                                                     EXHIBIT 4.6

                               F.N.B. CORPORATION

                              Amended and Restated
                   Officers' Certificate Pursuant to Indenture

         Pursuant to Sections 102 and 301 of the Indenture dated as of May 15,
1992 (the "Indenture), between F.N.B. Corporation (the "Company") and Northern
Central Bank, as Trustee (the "Trustee"), as amended, we Peter Mortensen,
Chairman and President, and David Mogle, Treasurer, respectively, of the
Company, hereby certify, in connection with the issuance by the Company of the
Securities described herein, that:

         (1)      There shall be the following three series of Securities
                  issuable under the Indenture and pursuant to this Officers'
                  Certificate: (i) Subordinated Term Notes (the "Term Notes"),
                  (ii) Subordinated Daily Notes (also sometimes referred to as
                  "Subordinated Daily Cash Account Notes" or "Subordinated Daily
                  Accounts") (the "Daily Notes"), and (iii) Subordinated Special
                  Daily Notes (the "Special Daily Notes") (the Term Notes, the
                  Daily Notes and the Special Daily Notes are sometimes
                  collectively referred to as the "Notes").

         (2)      There is no limit on the aggregate principal amount of Notes
                  that may be authenticated and delivered under the Indenture.

         (3)      The Term Notes will be due 3, 6, 9, 12, 15, 18, 21, 24, 27,
                  30, 36, 48, 60, 84 or 120 months from the date of issuance
                  thereof, according to their respective terms (the "Maturity
                  Date"), unless redeemed or extended as provided therein. The
                  Term Notes will be automatically extended for successive
                  terms, equal in duration to their original term, at the
                  rate(s) of interest then in effect for Term Notes of
                  comparable maturity unless, prior to maturity, the Company
                  receives notification of the Holder's intent to redeem the
                  Term Note. The principal amount of each Term Note shall be
                  payable in one lump sum on the Maturity Date thereof.

         (4)      The principal amount of each Daily Cash Account shall be due
                  and payable on demand; provided, however, that the Company
                  retains the right to require the Holder to give the Company no
                  less than 30 days prior written notice, by first class mail,
                  of a redemption in whole or in part demanded by the Holder,
                  which notice shall specify the principal amount of the Account
                  to be redeemed and the redemption date and, provided further,
                  that any partial redemption may not reduce the principal
                  amount of a Daily Cash Account Note to less than $50.

         (5)      The principal amount of each Daily Note and each Special Daily
                  Note shall be due and payable on demand; provided, however,
                  that (i) the Company retains the right to require the Holder
                  to give the Company no less than 30 days prior written notice,
                  by first class mail, of a redemption in whole or in part
                  demanded by the Holder, which notice shall specify the
                  principal amount of the Note to be redeemed and the redemption
                  date, (ii) a partial redemption may not reduce the principal
                  amount of a Daily Note to less than $50, (iii) a partial
                  redemption may not reduce the principal amount of a Special
                  Daily Note to less than the minimum purchase amount with
                  respect to Special Daily Notes in effect at the time of
                  issuance of the Special Daily Note to be redeemed, and (iv)
                  the minimum

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                  principal amount with respect to which a Special Daily Note
                  may be partially redeemed by the Holder thereof shall be
                  $2,500.

         (6)      The interest rates payable on the Daily Notes will be
                  determined by the Company and may fluctuate on a monthly
                  basis. Any adjustment to the interest rate will be made by the
                  Company on the first day of the month. Interest on the Daily
                  Notes shall accrue daily from the date of issuance and be
                  compounded quarterly. Accrued interest shall be paid to the
                  Holder of a Daily Note upon redemption in whole of the Note.
                  With respect to Daily Notes issued prior to April 15, 1999,
                  the interest rate will be no less than 3% below, or more than
                  5% above, the rate established for the most recent action
                  average of United States Treasury Bills with maturity of 13
                  weeks, subject to the limitation that in no event will the
                  rate of interest payable be more than 16% per annum or less
                  than 5% per annum.

         (6.1)    The rate of interest payable on the Special Daily Notes shall
                  be 8.0% per annum at all times prior to September 30, 2000.
                  Commencing October 1, 2000, the Company may, on the first day
                  of each calendar quarter (each such day referred to as an
                  "Adjustment Date") increase or decrease the rate of interest
                  payable on the Special Daily Notes; provided, however, that
                  (i) the annual rate of interest may not be reduced on any
                  Adjustment Date by more than 0.50% from the rate of interest
                  in effect on the day preceding such Adjustment Date, and (ii)
                  the rate of interest shall not be reduced below 6.5% per annum
                  at any time prior to December 31, 2002. Interest on the
                  Special Daily Notes will accrue daily from the date of
                  issuance and be compounded quarterly.

         (7)      Interest on the Notes which is payable, and is punctually paid
                  or duly provided for, on any Interest Payment Date shall be
                  paid to the Person in whose name that Note is registered at
                  the close of business 15 days prior to the Interest Payment
                  Date, which date shall constitute the Regular Record Date for
                  such interest payment. Interest not so paid or provided for
                  shall be paid as set forth in Section 307 of the Indenture.

         (8)      Interest on the Notes will be paid by checks mailed to the
                  holders of the Notes. Transfers of the Notes will be
                  registerable, Notes may be surrendered for exchange, and
                  principal of the Notes will be payable, at the branch offices
                  of Regency Finance Company and at the corporate trust office
                  of the Company located at Hermitage Square, Hermitage,
                  Pennsylvania.

         (9)      The Company will have the right, at its option, to call any of
                  the Notes for redemption before maturity at any time. Each
                  partial redemption payment shall be made ratably on all the
                  Outstanding Notes of the particular maturities called for
                  redemption. Interest on the Notes will continue to accrue
                  until the date of redemption and no premium shall be paid
                  thereon. The Company will give the Holder not less than thirty
                  (30) days' prior written notice by first class mail of each
                  redemption, specifying, among other things, the principal
                  amount of the Notes to be redeemed and the redemption date.
                  Notice of redemption having been given by the Company as
                  aforesaid, the principal amount of the Notes specified in such
                  notice, together with interest accrued and unpaid thereon to
                  the date of redemption, will become due and payable on such
                  redemption date.

         (10)     The Holder of a Term Note will have the right, at its option,
                  to redeem a Term Note prior to maturity. As to a 3, 6, 9 or 12
                  month Term Note, the Holder shall, upon such redemption,
                  forfeit an amount equal to one month of interest earned, or
                  that could have been earned, on the amount so redeemed at the
                  rate being paid on the Term Note, regardless of the length of
                  time that the Holder has owned the Term Note. As to an 18,

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                  24, 30, 36, 48, 60, 84 or 120 month Term Note, the Holder
                  shall forfeit an amount equal to 3 months of interest earned,
                  or that could have been earned, on the amount so redeemed at
                  the rate being paid on the Term Note, regardless of the length
                  of time that the Holder has owned the Term Note. Where
                  necessary to comply with the requirements of this paragraph,
                  interest already paid to or for the account of the Holder will
                  be deducted from the amount redeemed. Holders of Term Notes
                  will also have the right to make partial redemptions prior to
                  maturity; provided, however, that a partial redemption may not
                  reduce the outstanding principal amount of a Term Note to less
                  than $500. The above mentioned forfeitures will be calculated
                  only upon the principal amount of the Term Note. Term Notes
                  may be redeemed before maturity without forfeiture of interest
                  upon the death of any Holder or if the Holder is determined to
                  be legally incompetent by a court or any other administrative
                  body of competent jurisdiction. The Company retains the right
                  to require the Holder of any Term Note desiring to so redeem
                  the Term Note to give the Company not less than 30 days prior
                  written notice, by first class mail, of a redemption demanded
                  by the Holder, which notice shall specify the principal amount
                  of the Term Note to be redeemed and the redemption date.

         (11)     The Notes are issuable in any denomination; provided, however,
                  that (i) the minimum denomination for Term Notes shall be
                  $500, (ii) the minimum denomination for Daily Notes shall be
                  $50, and (iii) the Company may from time to time establish
                  minimum denominations for which Special Daily Notes shall be
                  issued.

         (12)     The Notes shall not be issued, in whole or in part, in the
                  form of a global Security or Securities.

         (13)     The Notes will be subordinate to the prior payment when due of
                  the principal of, and interest on, all Senior Indebtedness.

         (14)     The Trustee may appoint Regency Finance Company (or such other
                  entity as may be acceptable to the Company and the Trustee) as
                  Authenticating Agent for the Notes.

                  Capitalized terms used herein and not otherwise defined shall
         have the meanings given such terms in the Indenture.

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