Exhibit 23 Consent of Independent Accountants We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (File Nos. 33-8948, 33-22219, 333-04399, 333-42751 and 333-79199) of Zenith National Insurance Corp. of our report dated June 5, 2000 relating to the financial statements and supplemental schedules of The Zenith 401(k) Plan as of December 31, 1999 and 1998, and for the year ended December 31, 1999, which appears in this Form 11-K. PricewaterhouseCoopers LLP Los Angeles, California June 9, 2000