Exhibit 23 Consent of Independent Auditors Exhibit 23 Consent of Independent Auditors We consent to the incorporation by reference in the following Registration Statements and related prospectuses of State Auto Financial Corporation of our report dated February 21, 2003, with respect to the consolidated financial statements and schedules of State Auto Financial Corporation and subsidiaries included in this Annual Report (Form 10-K) for the year ended December 31, 2002. Registration Form Number(s) Description - ---------------------------------------------------------------------------------------- S-8 33-44667 1991 Stock Option Plan 33-89400 S-8 33-44666 1991 Directors' Stock Option Plan S-8 33-41423 1991 Employee Stock Purchase and Dividend Reinvestment Plan 333-05755 S-8 333-56336 State Auto Insurance Companies Capital Accumulation Plan S-8 333-43882 2000 Directors' Stock Option Plan S-8 333-43880 2000 Stock Option Plan S-3 333-41849 Monthly Stock Purchase Plan for Independent Agents S-3 333-90529 1998 State Auto Agents' Stock Option Plan Columbus, Ohio /s/ Ernst & Young, LLP March 25, 2003 Report of Independent Auditors The Board of Directors and Stockholders State Auto Financial Corporation We have audited the accompanying consolidated balance sheets of State Auto Financial Corporation and subsidiaries as of December 31, 2002 and 2001, and the related consolidated statements of income, stockholders' equity and cash flows for each of the three years in the period ended December 31, 2002. Our audits also included the financial statement schedules listed in the Index at Item 15(a)(2). These financial statements and schedules are the responsibility of the Company's management. Our responsibility is to express an opinion on these financial statements and schedules based on our audits. We conducted our audits in accordance with auditing standards generally accepted in the United States. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion. In our opinion, the financial statements referred to above present fairly, in all material respects, the consolidated financial position of State Auto Financial Corporation and subsidiaries at December 31, 2002 and 2001, and the consolidated results of their operations and their cash flows for each of the three years in the period ended December 31, 2002, in conformity with accounting principles generally accepted in the United States. Also, in our opinion, the related financial statement schedules, when considered in relation to the basic financial statements taken as a whole, present fairly in all material respects the information set forth therein. Columbus, Ohio /s/ Ernst & Young, LLP February 21, 2003