8-K

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) March 22, 2005

OHIO CASUALTY CORPORATION

(Exact name of registrant as specified in its charter)

OHIO

(State or other jurisdiction of incorporation or organization)

Commission File Number 0-5544

31-0783294

(I.R.S. Employer Identification No.)

9450 Seward Road

Fairfield, Ohio

(Address of principal executive offices)

45014

(Zip Code)

(513) 603-2400

(Registrant’s telephone number)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

ITEM 8.01.  OTHER EVENTS

On March 22, 2005, Ohio Casualty announced the expiration and results of its offer to exchange up to $184,250,000 in aggregate principal amount of its 5.00% Convertible Notes due 2022 (the “New Notes”) for its outstanding 5.00% Convertible Notes due 2022 (the “Old Notes”). A copy of the press release is attached hereto as Exhibit 99.1 and incorporated herein by reference.

Item 9.01.  FINANCIAL STATEMENTS AND EXHIBITS.

(c) Exhibits.

99.1 Press release dated March 22, 2005 issued by Ohio Casualty Corporation and posted on the Corporation’s website at http://www.ocas.com.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

OHIO CASUALTY CORPORATION

(Registrant)

/s/ Debra K. Crane

Debra K. Crane

Senior Vice President, General Counsel and Secretary

Date: March 22, 2005

EXHIBIT INDEX

Exhibit Number	Exhibit
99.1	Press release dated March 22, 2005 issued by Ohio Casualty Corporation and posted on the Corporation’s website at http://www.ocas.com.

EX-99.1

Exhibit 99.1

OHIO CASUALTY CORPORATION ANNOUNCES EXPIRATION AND RESULTS

OF EXCHANGE OFFER

FAIRFIELD, Ohio, March 22, 2005 — Ohio Casualty Corporation (“Ohio Casualty”) (Nasdaq: OCAS) announced today the expiration and results of its offer to exchange up to $184,250,000 in aggregate principal amount of its 5.00% Convertible Notes due 2022 (the “New Notes”) for its outstanding 5.00% Convertible Notes due 2022 (the “Old Notes”).

The exchange offer expired at 12:00 midnight, New York City time, on March 21, 2005. Approximately $67,279,000 million aggregate principal amount, representing approximately 36.5 percent of the outstanding principal amount of the Old Notes, were tendered for exchange. Ohio Casualty has accepted all validly tendered Old Notes and, in exchange, will issue a like principal amount of New Notes and pay a cash exchange fee of $3.50 for each $1,000 principal amount of the Old Notes exchanged. The New Notes will be issued promptly to holders who properly tendered Old Notes in accordance with the terms of the exchange offer.

This press release is for informational purposes only and is not an offer to buy or the solicitation of an offer to sell the Old Notes, the New Notes or Ohio Casualty’s common shares. The offer was made only by means of the Offering Memorandum, as amended by Amendments No. 1 and No. 2 to Schedule TO, and the related Letter of Transmittal which was sent to holders of Old Notes and was filed with the Securities and Exchange Commission as a part of Ohio Casualty’s Tender Offer Statement on Schedule TO, as amended. The Tender Offer Statement, and amendments thereto, are available for no charge at the Securities and Exchange Commission’s Website at www.sec.gov. The exchange offer was exempt from the registration requirements of the Securities Act of 1933, as amended, pursuant to Section 3(a)(9) thereof. Ohio Casualty did not pay or give, directly or indirectly, any commission or other remuneration, including underwriting discounts, to any broker, dealer, salesman or other person for soliciting tenders of the Old Notes in connection with the Exchange Offer, and the Company did not retain any dealer, manager or other agent to solicit tenders with respect to the Exchange Offer.

Ohio Casualty Corporation is the holding company of The Ohio Casualty Insurance Company, which is one of six property-casualty companies that make up Ohio Casualty Group^®. The Ohio Casualty Insurance Company was founded in 1919 and is licensed in 49 states. Ohio Casualty Group is ranked 48th among U.S. property/casualty insurance groups based on net premiums written (Best’s Review, July 2004).

The information above includes forward-looking statements within the meaning of the Securities Act of 1933, as amended and the Securities Exchange Act of 1934, as amended. Such forward-looking statements are subject to certain risks and uncertainties, as disclosed by Ohio Casualty from time to time in its filings with the Securities and Exchange Commission. As a result of these factors, Ohio Casualty’s actual results may differ materially from those indicated or implied by such forward-looking statements.

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Media Contact: Cindy L. Denney, Assistant Vice President, Corporate Communications, (513) 603-2074

Investment Analyst Contact: Dennis E. McDaniel, Vice President of Strategic Planning and Investor Relations, (513) 603-2197

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