UNITED STATES

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 4, 2013

Asset Acceptance Capital Corp.

(Exact name of Registrant as specified in its charter)

28405 Van Dyke Avenue

Warren, MI 48093

(Address of principal executive offices)

Registrant’s telephone number, including area code: (586) 939-9600

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:

Item 7.01 Regulation FD Disclosure.

On March 4, 2013, Asset Acceptance Capital Corp., a Delaware corporation (“the Company”) announced that it was postponing its 2012 fourth quarter and year-end earnings release and conference call from March 4, 2013 to March 6, 2013. On March 6, 2013, the Company announced its reported results for the quarter and fiscal year ended December 31, 2012 and, in a separate press release, announced that the Company had entered into a merger agreement with Encore Capital Group, Inc. As a result of its entrance into the merger agreement, the Company further announced on March 6, 2013 that it would no longer host the earnings call previously scheduled to occur on that day. For informational purposes only, the Company is disclosing its prepared remarks that would have been used had the earnings call been held on March 6, 2013. A copy of the prepared remarks has been posted on the Company’s website and is attached as Exhibit 99.1 hereto.

Additional Information and Where to Find It

This filing may be deemed solicitation material in respect of the proposed acquisition of the Company and the respective affiliates. In connection with the proposed merger transaction, the Company will file with the SEC and furnish to the Company’s stockholders a proxy statement and other relevant documents. BEFORE MAKING ANY VOTING DECISION, THE COMPANY’S STOCKHOLDERS ARE URGED TO READ THE PROXY STATEMENT IN ITS ENTIRETY WHEN IT BECOMES AVAILABLE AND ANY OTHER DOCUMENTS TO BE FILED WITH THE SEC IN CONNECTION WITH THE PROPOSED MERGER OR INCORPORATED BY REFERENCE IN THE PROXY STATEMENT BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED MERGER AND THE PARTIES TO THE MERGER. The Company’s stockholders will be able to obtain a free copy of documents filed with the SEC at the SEC’s website at http://www.sec.gov. In addition, the Company’s stockholders may obtain a free copy of the Company’s filings with the SEC from the Company’s website at http://investors.assetacceptance.com/phoenix.zhtml?c=148416&p=irol-sec or by directing a request to: Mary Arraf, 586-983-7087 or via e-mail at marraf@assetacceptance.com

Participants in the Solicitation

The directors, executive officers and certain other members of management and employees of the Company may be deemed “participants” in the solicitation of proxies from stockholders of the Company in favor of the proposed merger. Information regarding the persons who may, under the rules of the SEC, be considered participants in the solicitation of the stockholders of the Company in connection with the proposed merger will be set forth in the proxy statement and the other relevant documents to be filed with the SEC. You can find information about the Company’s executive officers and directors in its Annual Report on Form 10-K for the fiscal year ended December 31, 2012, filed on March 7, 2013 and in its definitive proxy statement filed with the SEC on Schedule 14A on March 28, 2012.

Forward-looking Statements

Statements in this Current Report on Form 8-K and the exhibits filed herewith that relate to future results and events are forward-looking statements based on the Company’s current expectations. Actual results and events in future periods may differ materially from those expressed or implied by these forward-looking statements because of a number of risks, uncertainties and other factors. All statements other than statements of historical fact, including statements containing the words “intends,” “believes,” “expects,” “will,” and similar expressions, are statements that could be deemed to be forward-looking statements. Risks, uncertainties and other factors include, but are not limited to: (1) the occurrence of any event, change or other circumstances that could give rise to the termination of the merger agreement; (2) the inability to complete the proposed merger due to the failure to obtain stockholder approval for the proposed merger or the failure to satisfy other conditions to completion of the proposed merger, including that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (3) risks related to disruption of management’s attention from the Company’s ongoing business operations due to the transaction; and (4) the effect of the announcement of the proposed merger on the Company’s relationships with its customers, suppliers, employees, operating results and business generally.

Actual results may differ materially from those indicated by such forward-looking statements. In addition, the forward-looking statements represent the Company’s views as of the date as of which they were made. The Company anticipates that subsequent events and developments will cause its views to change. However, although the Company may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing the Company’s views as of any date subsequent to the date hereof. Additional factors that may cause results to differ materially from those described in the forward—looking statements are set forth in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2012, filed with the SEC on March 7, 2013, under the heading “Item 1—A Risk Factors,” and in prior reports on Forms 10-Q and 8-K filed with the SEC by the Company.

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EXHIBIT INDEX

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SIGNATURES

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.

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