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                                 EXHIBIT 10.11
                     AMENDMENT TO LINE OF CREDIT AGREEMENT
 
    This First Amendment to Line of Credit Agreement (the "Amendment") is made
and entered into this 28th day of December, 1995, by and between SANWA BANK
CALIFORNIA (the "Bank") and ZENITH NATIONAL INSURANCE CORP. (the "Borrower")
with respect to the following:
 
    This Amendment shall be deemed to be a part of and subject to that certain
Line of Credit Agreement dated as of December 15, 1995 as it may be amended from
time to time, and any and all addenda and riders thereto (collectively the
"Agreement"). Unless otherwise defined herein, all terms used in this Amendment
shall have the same meanings as in the Agreement. To the extent that any of the
terms or provisions of this Amendment conflict with those contained in the
Agreement, the terms and provisions contained herein shall control.
 
    WHEREAS,  the Borrower and the Bank mutually desire to extend and/or modify
the Agreement.
 
    NOW THEREFORE,  for value received and hereby acknowledged, the Borrower and
the Bank agree as follows:
 
        1.  CHANGE IN REPORTING REQUIREMENTS.  Section 4.05 C., D., and E. of
    the Agreement are deleted in their entirety and the following is substituted
    in lieu thereof:
 
            "C. TRI-ANNUAL AUDIT. Not later than 30 days after the Borrower
            receives it, a copy of the tri-annual audit of Zenith Insurance
            Company prepared by the Department of Insurance.
 
            D. QUARTERLY STATUTORY STATEMENTS. Not later than 75 days after the
            end of the first three quarters of each fiscal year of the Borrower,
            copies of the quarterly statutory statement of Zenith Insurance
            Company and its consolidated insurance subsidiaries.
 
            E. ANNUAL STATUTORY STATEMENTS. Not later than 120 days after the
            end of each of the Borrower's fiscal years, copies of the annual
            statutory statements of Zenith Insurance Company and its
            consolidated insurance subsidiaries".
 
        2.  MODIFICATION OF ADDITIONAL INDEBTEDNESS.  Section 4.06 of the
    Agreement is deleted in its entirety and the following is substituted in
    lieu thereof:
 
            4.06 ADDITIONAL INDEBTEDNESS OF INSURANCE SUBSIDIARIES. Borrower's
            consolidated insurance subsidiaries shall not, after the date
            hereof, create, incur or assume, directly or indirectly, any
            Indebtedness exceeding in the aggregate the amount of
            $20,000,000.00. The term "Indebtedness", as used in this Agreement
            with respect to the Borrower or each of its subsidiaries, as
            applicable, shall mean, at any date, the aggregate amount, excluding
            in all cases the amount of indebtedness owed to a corporate
            affiliate, of, without duplication, (a) all obligations for borrowed
            money from banks including, but not limited to, guaranties and
            letters of credit, (b) all obligations evidenced by bonds,
            debentures, notes or similar instruments, (c) all obligations to pay
            the deferred purchase price of property or services, (d) capitalized
            lease obligations, (e) all obligations or liabilities of others
            secured by a lien on any asset whether or not such obligation or
            liability is assumed, and (f) any other obligations or liabilities
            which are required by generally accepted accounting principles to be
            shown as debt on a balance sheet".
 
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        3.  CHANGE IN FINANCIAL CONDITION.  Section 4.10 C. of the Agreement is
    deleted in its entirety and the following is substituted in lieu thereof:
 
            "C. AGGREGATE STATUTORY SURPLUS. Zenith Insurance Company and its
            consolidated insurance subsidiaries shall maintain an aggregate
            statutory surplus of at least $140,000,000.00".
 
        4.  MODIFICATION OF CORPORATE RATING.  Section 4.13 of the Agreement is
    deleted in its entirety and the following is substituted in lieu thereof:
 
            "4.13 CORPORATE RATING. Zenith Insurance Company (on a pooled or
            individual basis) shall maintain at all times an A.M. Best rating of
            no lower than B+".
 
        5.  CONFIRMATION OF OTHER TERMS AND CONDITIONS OF THE AGREEMENT.  Except
    as specifically provided in this Amendment, all other terms, conditions and
    covenants of the Agreement unaffected by this Amendment shall remain
    unchanged and shall continue in full force and effect and the Borrower
    hereby covenants and agrees to perform and observe all terms, covenants and
    agreements provided for in the Agreement, as hereby amended.
 
    IN WITNESS WHEREOF,  this Amendment has been executed by the parties hereto
as of the date first hereinabove written.
 
<TABLE>
<CAPTION>
BANK:                                         BORROWER:
<S>                                           <C>
SANWA BANK CALIFORNIA                         ZENITH NATIONAL INSURANCE CORP.
                      By:      JOHN C. HYCHE                       By:      STANLEY R. ZAX
    ----------------------------------------      ----------------------------------------
                       Name:   JOHN C. HYCHE                        Name:   STANLEY R. ZAX
       -------------------------------------         -------------------------------------
                    Title:    Vice President       Title:    President and Chairman of the
      --------------------------------------                                         Board
                                                    --------------------------------------
</TABLE>
 
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