AHL Aspen Insurance Holdings Limited Ordinary Shares

Aspen Insurance Holdings Limited (NYSE:AHL) today announced that A.M. Best has increased the financial strength rating of Aspen�s Bermuda subsidiary, Aspen Insurance Limited, to �A� with a �Stable� outlook, and affirmed the �A� rating of Aspen Insurance UK Limited and upgraded the outlook to �Stable�. These actions harmonise the ratings of both entities. According to A.M. Best the ratings reflect the excellent financial strength of the consolidated Aspen group, the operating performance of the Bermuda and UK companies, anticipation of continued strong underwriting results, the strength of the Aspen brand and its well diversified business model. Richard Houghton, Chief Financial Officer of Aspen said, �We believe that the �A� ratings from A.M. Best are important endorsements of Aspen�s strategy and financial strength.� About Aspen Insurance Holdings Limited Aspen provides reinsurance and insurance coverage to clients in various domestic and global markets through wholly-owned subsidiaries and offices in Bermuda, France, the United States, the United Kingdom, and Switzerland. For the nine months ended September 30, 2007, Aspen reported gross written premiums of $1.5 billion, net income of $353.8 million and total assets of $7.3 billion. For more information about Aspen, please visit www.aspen.bm. Aspen�s Ratings Aspen Insurance UK Limited Aspen Insurance Limited A (Strong) Standard & Poor's A (Strong) Standard & Poor's A (Excellent) A.M. Best A (Excellent) A.M. Best A2 (Good) Moody's A2 (Good) Moody's Aspen Specialty Insurance Company A- (Excellent) A.M. Best Application of the Safe Harbor of the Private Securities Litigation Reform Act of 1995: This press release contains written, and Aspen's officers may make related oral, "forward-looking statements" within the meaning of the U.S. federal securities laws regarding its capital management plans, its outlook and financial results. These statements are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include all statements that do not relate solely to historical or current facts, and can be identified by the use of words such as "expect," "intend," "plan," "believe," "project," "anticipate," "seek," "will," "estimate," "may," "continue," and similar expressions of a future or forward-looking nature. All forward-looking statements rely on a number of assumptions, estimates and data concerning future results and events and are subject to a number of uncertainties and other factors, many of which are outside Aspen's control that could cause actual results to differ materially from such statements. For a detailed description of uncertainties and other factors that could impact the forward-looking statements in this release, please see the "Risk Factors" section in Aspen's Annual Report on Form 10-K for the year ended December 31, 2006, filed with the U.S. Securities and Exchange Commission on February 22, 2007.