EXHIBIT 23

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-107041) pertaining to the United Fire Group 401(k) Plan of United Fire & Casualty Company of our report dated June 29, 2005, with respect to the financial statements and schedule of United 401(k) Profit Sharing Plan included in this annual report (Form 11-K) for the year ended December 31, 2004.

/s/ Ernst & Young LLP

Chicago, Illinois

June 29, 2005

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