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                                                                    EXHIBIT 4(d)


                               THIRD AMENDMENT TO
                                CREDIT AGREEMENT

         This Third Amendment to the Credit Agreement (the "Amendment") is
entered as of this 24th day of November, 1999, by and between FIFTH THIRD BANK,
CENTRAL OHIO, an Ohio banking corporation (the "Bank") and BANCINSURANCE
CORPORATION, an Ohio corporation (the "Borrower").

         WHEREAS, Bank and Borrower entered into that certain Credit Agreement,
dated as of January 25, 1993, as amended by the First Amendment thereto, dated
November 5, 1993 and the Second Amendment thereto, dated October 19, 1994 (the
"Agreement");

         WHEREAS, Borrower executed and delivered to Bank a Revolving Note,
dated January 25, 1993, in the original principal amount of $6,000,000 (the
"Note");

         WHEREAS, the terms of the Note were amended and restated pursuant to
Amended and Restated Notes, dated November 5, 1993, October 19, 1994, July 19,
1995, June 4, 1996, July 17, 1997 and September 1, 1998, in the principal amount
of $ 10,000,000; and

         WHEREAS, Borrower and Bank desire to amend the Agreement and the Note
to extend the term thereof and to change certain financial covenants contained
in the Agreement, subject to the terms and conditions set forth herein;

         NOW THEREFORE, intending to be legally bound, the parties hereto agree
as follows:

         1.       AMENDMENTS.

         (a) Section 2, Subsections 2. 1 (a) and (b) of the Agreement are hereby
amended and restated in their entirety to read as follows:

             2.1 REVOLVING CREDIT LOANS. (a) Subject to the terms and conditions
hereof, Bank hereby extends to Borrower a line of credit facility (the
"Facility") under which Bank will make loans (the "Revolving Loans") to Borrower
in an aggregate amount to not exceed $10,000,000. Bank may create and maintain
reserves from time to time based on such credit considerations as Bank may deem
appropriate. Borrower may borrow, prepay (without penalty or charge) and
reborrow under the Facility, provided that the principal amount of all Revolving
Loans outstanding at any one time under the Facility will not exceed
$10,000,000. If the amount of the Revolving Loans outstanding at any time under
the Facility exceeds such amount, Borrower shall immediately pay the amount of
such excess to Bank in cash.

             (b) On the date of execution of the Third Amendment to Credit
Agreement (the "Amendment"), Borrower shall duly execute and deliver to Bank an
amended and restated Revolving Note in the form attached as Exhibit 2.1 to the
Amendment, in the principal amount of $10,000,000, bearing interest as specified
in such Revolving Note (the "Revolving Note") and will be delivered to Bank in
substitution for the Note most recently executed by Borrower on September 1,
1998, in the principal amount of $10,000,000.

         (b) Section 5, Subsection 5.5 of the Agreement is hereby amended and
restated in its entirety to read as follows:

             5.5 STATUTORY NET WORTH. Borrower will not permit the tangible
             net worth of Ohio Indemnity Company ("policy holder surplus"
             in statutory reporting) to be less than $18,000,000 on each
             December 31 throughout the term of this Agreement, as
             determined in accordance with accounting standards promulgated
             by the Ohio Department of Insurance.

         2. REPRESENTATIONS, WARRANTIES AND COVENANTS OF BORROWER. To induce
Bank to enter into this Amendment, Borrower represents and warrants as follows:

         (a)      The representations and warranties of Borrower contained in
                  Section 3 of the Agreement are deemed to have been made again
                  on and as of the date of execution of this Amendment, and are
                  true and correct as of the date of execution hereof.

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         (b)      No Event of Default (as such term is defined in Section 6 of
                  the Agreement) or event or condition which, with the lapse of
                  time or giving of notice or both, would constitute an Event of
                  Default exists on the date hereof.

         (c)      The person executing this Amendment and the Amended and
                  Restated Revolving Note, is a duly elected and acting officer
                  of Borrower and is duly authorized by the Board of Directors
                  of Borrower to execute and deliver this Amendment and such
                  note on behalf of Borrower.

         3. CONDITIONS. Bank's obligations under this Amendment are subject to
the following conditions:

         (a)      Borrower shall have executed and delivered to Bank the Amended
                  and Restated Revolving Note in the form attached hereto as
                  Exhibit 2. 1.

         (b)      The Bank shall have been furnished copies, certified by the
                  Secretary or assistant Secretary of Borrower, of resolutions
                  of the Board of Directors of Borrower authorizing the
                  execution of this Amendment, the Exhibits hereto and all other
                  documents executed in connection herewith which resolutions
                  will be in the form attached hereto as Exhibit A.

         (c)      The representations and warranties of Borrower in Section 2
                  hereof shall be true and correct on the date of execution of
                  this Amendment.

         4.       GENERAL.

         (a)      Except as expressly modified hereby, the Agreement remains
                  unaltered and in full force and effect. Borrower acknowledges
                  that Bank has made no oral representations to Borrower with
                  respect to the Agreement and this Amendment thereto and that
                  all prior understandings between the parties are merged into
                  the Agreement as amended by this writing. All Loans
                  outstanding on the date of execution of this Amendment shall
                  be considered for all purposes to be Loans outstanding under
                  the Agreement as amended by this Amendment.

         (b)      Capitalized terms used and not otherwise defined herein will
                  have the meanings set forth in the Agreement.

         (c)      Nothing contained herein will be construed as waiving any
                  default or Event of Default under the Agreement or will affect
                  or impair any right, power or remedy of the Bank under or with
                  respect to the Loans, the Agreement, as amended, the Note, as
                  amended and restated, or any agreement or instrument
                  guaranteeing, securing or otherwise relating to the Loans.

         (d)      This Amendment shall be considered an integral part of the
                  Agreement, and all references to the Agreement in the
                  Agreement itself or any document referring thereto shall, on
                  and after the date of execution of this Amendment, be deemed
                  to be references to the Agreement as amended by this
                  Amendment.

         (e)      This Amendment will be binding upon and inure to the benefit
                  of Borrower and Bank and their respective successors and
                  assigns.

         (f)      All representations, warranties and covenants made by Borrower
                  herein will survive the execution and delivery of this
                  Amendment.

         (g)      This Amendment will, in all respects, be governed and
                  construed in accordance with the laws of the State of Ohio.

         (h)      This Amendment may be executed in one or more counterparts,
                  each of which will be deemed an original and all of which
                  together will constitute one and the same instrument.


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         (i)      Borrower authorizes any attorney of record to appear for it in
                  any court of record in the State of Ohio, after an Obligation
                  becomes due and payable whether by its terms or upon default,
                  waives the issuance and service of process, releases all
                  errors and rights of appeal, and confesses a judgment against
                  it in favor of the holder of such Obligation, for the
                  principal amount of such Obligation plus interest thereon,
                  together with court costs and attorneys' fees. Stay of
                  Execution and all exemptions are hereby waived. Borrower also
                  agrees that the attorney acting for Borrower as set forth in
                  this paragraph may be compensated by Bank for such services,
                  and Borrower waives any conflict of interest caused by such
                  representation and compensation arrangement. If an Obligation
                  is referred to an attorney for collection, and the payment is
                  obtained without the entry of a judgment, the obligors will
                  pay to the holder of such Obligation its attorneys' fees.

         The undersigned acknowledges and agrees to be bound by the terms and
provisions of only Section 5.2 of the Agreement.

                                        OHIO INDEMNITY COMPANY


                                        By:    /s/ John Sokol
                                           -------------------------------------

                                        Its:   President
                                           -------------------------------------

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         IN WITNESS WHEREOF, Borrower and Bank have executed this Agreement by
their duly authorized officers as of the date first above written.

         WARNING - BY SIGNING THIS PAPER, YOU GIVE UP YOUR RIGHT TO NOTICE AND
         COURT TRIAL. IF YOU DO NOT PAY ON TIME, A COURT JUDGMENT MAY BE TAKEN
         AGAINST YOU WITHOUT YOUR PRIOR KNOWLEDGE AND THE POWERS OF A COURT CAN
         BE USED TO COLLECT FROM YOU REGARDLESS OF ANY CLAIMS YOU MAY HAVE
         AGAINST THE CREDITOR WHETHER FOR RETURNED GOODS, FAULTY GOODS, FAILURE
         ON HIS PART TO COMPLY WITH THE AGREEMENT OR ANY OTHER CAUSE.


                                        BANCINSURANCE CORPORATION


                                        By:       /s/ John Sokol
                                           -------------------------------------

                                        Its:      President
                                           -------------------------------------


                                        FIFTH THIRD BANK, CENTRAL OHIO


                                        By:       Ted Lape
                                           -------------------------------------

                                        Its:      Vice President
                                           -------------------------------------