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                                                                    EXHIBIT 10.1

                      SEVENTH AMENDMENT TO CREDIT AGREEMENT

         THIS SEVENTH AMENDMENT TO CREDIT AGREEMENT, dated as of the 27th day of
June, 2003 (this "Amendment"), is made among SELECTIVE INSURANCE GROUP, INC., a
New Jersey corporation with its principal offices in Branchville, New Jersey
("Parent"), and SELECTIVE INSURANCE COMPANY OF AMERICA, a New Jersey corporation
with its principal offices in Branchville, New Jersey ("SICA," and collectively
with the Parent, the "Borrowers"), and WACHOVIA BANK, NATIONAL ASSOCIATION
(formerly known as First Union National Bank) ("Lender"). Capitalized terms used
but not defined herein shall have the meanings given to such terms in the Credit
Agreement referred to below, as amended by this Amendment. Unless otherwise
specified, section references herein refer to sections set forth in the Credit
Agreement, as amended by this Amendment.

                                    RECITALS

         A.       The Borrowers and the Lender are parties to a Credit
Agreement, dated as of October 22, 1999, as amended (the "Credit Agreement"),
providing for the availability of a revolving credit facility to the Borrower
upon the terms and conditions set forth therein.

         B.       The Borrower has requested an extension of the maturity of
such revolving credit facility, as more fully set forth herein, and the Lender
has agreed to such extension upon the terms and conditions set forth herein.

                             STATEMENT OF AGREEMENT

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto, for themselves
and their successors and assigns, agree as follows:

                                   ARTICLE II

                          AMENDMENT TO CREDIT AGREEMENT

         2.1      Section 1.1 is hereby amended by adding the following
definition thereto in appropriate alphabetical order:

         "        "Amendment Fee Letter" shall mean the letter from Wachovia to
         the Parent, dated June 26, 2003, relating to certain fees payable by
         the Borrower in respect of the transactions contemplated by the Seventh
         Amendment, as amended, modified or supplemented from time to time."

         "        "Seventh Amendment" shall mean the Seventh Amendment to Credit
         Agreement, dated as of June 27, 2003, among the Borrowers and the
         Lender, which amends this Agreement."

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         2.2      Section 1.1 is hereby further amended by replacing the
following definitions, as currently set forth therein, with the definitions as
set forth below:

         "        "Adjusted LIBOR Rate" shall mean, at any time with respect to
         any Loan, a rate per annum equal to the LIBOR Rate as in effect at such
         time plus 0.65% (65 basis points)."

         "        "Agreement" shall mean this Credit Agreement, as amended by
         the First Amendment, the Second Amendment, the Third Amendment, the
         Fourth Amendment, the Fifth Amendment, the Sixth Amendment, and the
         Seventh Amendment and as further amended, modified or supplemented from
         time to time."

         "        "Maturity Date" shall mean June 26, 2004 or such later date to
         which the Maturity Date may be extended pursuant to Section 2.18."

         2.3      Section 2.9(a) is hereby amended by replacing the reference
therein to "0.125%" with "0.14%."

         2.4      Section 2.18 is hereby amended by replacing the references
therein to "June 27, 2003" with "June 26, 2004."

         2.5      Section 9.5(a) is deleted in its entirety and is replaced with
the following:

         "        (a)   if to the Borrowers, to Selective Insurance Group, Inc.,
                  40 Wantage Avenue, Branchville, New Jersey 07890, Attention:
                  Dale A. Thatcher, Chief Financial Officer and Treasurer,
                  Telecopy No. (973) 948-0282, with a copy to Selective
                  Insurance Group, Inc. Attention: Richard W. Berstein, General
                  Counsel, Telecopy No. (973) 948-0282;

         2.6      Section 9.5(b) is deleted in its entirety and is replaced with
the following:

         "        (b)   if to the Lender, to it at the address set forth on its
         signature page to the Seventh Amendment;"

         2.7      Section 6.1 is hereby amended by replacing the reference
therein to "$365,000,000" with "$390,000,000."

         2.8      The Credit Agreement is further amended by adding the
following new Section 5.12 thereto:

         "5.12 Reciprocal Benefit. If the Borrowers shall agree to different or
         additional covenants, representations or defaults in connection with
         the Indebtedness referred to in clause (b) of Section 7.2(iii), the
         Borrowers shall give Lender prompt written notice of such different or
         additional covenants, representations, or defaults (enclosing a copy
         thereof), and Lender shall have the right (but not the obligation) to
         have any or all of such different or additional covenants,
         representations or defaults incorporated by reference into the Credit
         Agreement by written notice to the Borrowers specifying the particular
         covenants, representations and/or defaults to be incorporated by
         reference into the Credit Agreement."

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                                   ARTICLE III

                                  EFFECTIVENESS

         This Amendment shall become effective on June 27, 2003 (the "Seventh
Amendment Effective Date"), provided that the following conditions shall have
been satisfied as of such date:

         3.1      Representations and Warranties; Officer's Certificate. The
following shall be true and the Lender shall have received a certificate, signed
by the president, chief executive officer or chief financial officer of each
Borrower, dated the Seventh Amendment Effective Date, in form and substance
satisfactory to the Lender, certifying that (i) each of the representations and
warranties of such Borrower contained in this Amendment, the Credit Agreement
and the other Credit Documents is true and correct on and as of the Seventh
Amendment Effective Date and after giving effect to this Amendment with the same
effect as if made on and as of such date (except to the extent any such
representation or warranty is expressly stated to have been made as of a
specific date, in which case such representation or warranty is true and correct
as of such date), and (ii) on and as of the Seventh Amendment Effective Date and
after giving effect to this Amendment, no Default or Event of Default has
occurred and is continuing.

         3.2      Amendment Fee. The Borrowers shall have paid to Wachovia the
unpaid amount of the fee described in the Amendment Fee Letter.

         3.3      Secretary's Certificates. With respect to each Borrower, the
Lender shall have received a certificate, signed by the secretary or an
assistant secretary of such Borrower, dated the Seventh Amendment Effective
Date, in form and substance satisfactory to the Lender, certifying that (i)
since October 22, 1999, there has been no amendment to the articles of
incorporation or bylaws of such Borrower (or, if and to the extent any of the
foregoing have been amended since such date, a statement to such effect,
attaching copies thereof), and (ii) attached thereto is a true and complete copy
of resolutions adopted by the board of directors of such Borrower authorizing
the execution, delivery and performance of this Amendment.

         3.4      Fees and Expenses. The Borrower shall have paid all fees and
expenses of the Lender required under the Credit Agreement to have been paid on
or prior to the Seventh Amendment Effective Date, including without limitation
the reasonable fees and expenses of counsel to the Lender.

         3.5      No Material Adverse Change. Since December 31, 2002, there
shall not have occurred any Material Adverse Change.

         3.6      Other Documents. The Lender shall have received such other
documents, certificates, opinions and instruments in connection with this
Amendment as it shall have reasonably requested.

                                   ARTICLE IV

                         REPRESENTATIONS AND WARRANTIES

         Each of the Borrowers hereby represents and warrants to the Lender
that, after giving effect to this Amendment:

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         (a)      Each of the representations and warranties of such Borrower
contained in the Credit Agreement is true and correct on and as of the date
hereof with the same effect as if made on and as of the date hereof (except to
the extent any such representation or warranty is expressly stated to have been
made as of a specific date, in which case such representation or warranty is
true and correct as of such date).

         (b)      On and as of the Seventh Amendment Effective Date, no Default
or Event of Default has occurred and is continuing.

                                    ARTICLE V

                                     GENERAL

         5.1      Full Force and Effect. From and after the Seventh Amendment
Effective Date, all references to the Credit Agreement set forth in any other
Credit Document or other agreement or instrument shall, unless otherwise
specifically provided, be references to the Credit Agreement as amended by this
Amendment and as may be further amended, modified, restated or supplemented from
time to time. This Amendment is limited as specified and shall not constitute or
be deemed to constitute an amendment, modification or waiver of, or consent to
departure from, any provision of the Credit Agreement except as expressly set
forth herein. Except as expressly amended hereby, the Credit Agreement shall
remain in full force and effect in accordance with its terms.

         5.2      Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York, without regard
to principles of conflict of laws (excluding New York General Obligations Law
Section 5-1401).

         5.3      Counterparts. This Amendment may be executed in two or more
counterparts, each of which shall constitute an original, but all of which when
taken together shall constitute but one instrument.

         5.4      Construction. The headings of the various sections and
subsections of this Amendment have been inserted for convenience only and shall
not in any way affect the meaning or construction of any of the provisions
hereof.

         5.5      Severability. To the extent any provision of this Amendment is
prohibited by or invalid under the applicable law of any jurisdiction, such
provision shall be ineffective only to the extent of such prohibition or
invalidity and only in any such jurisdiction, without prohibiting or
invalidating such provision in any other jurisdiction or the remaining
provisions of this Amendment in any jurisdiction.

         5.6      Successors and Assigns. This Amendment shall be binding upon,
inure to the benefit of and be enforceable by the respective successors and
permitted assigns of the parties hereto.

                   [signatures appear on the following pages]

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         IN WITNESS WHEREOF, each of the parties hereto has caused this
Amendment to be executed by its duly authorized officer as of the day and year
first above written.

                                SELECTIVE INSURANCE GROUP, INC.

                                By: /s/ Gregory E. Murphy
                                    --------------------------------------------

                                Name: Gregory E. Murphy

                                Title: Chairman and Chief Executive Officer

                                SELECTIVE INSURANCE COMPANY OF AMERICA

                                By: /s/ Gregory E. Murphy
                                    --------------------------------------------

                                Name: Gregory E. Murphy

                                Title: Chairman and Chief Executive Officer

                              (signatures continue)

                                SIGNATURE PAGE TO
                                SEVENTH AMENDMENT

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                                WACHOVIA BANK, NATIONAL ASSOCIATION
                                (formerly known as First Union National Bank)

                                By: /s/ Kimberly Shaffer
                                    --------------------------

                                Name: Kimberly Shaffer

                                Title: Director

                               SIGNATURE PAGE TO
                               SEVENTH AMENDMENT