Argo Group International Holdings, Ltd. (NasdaqGS: AGII) announced today that it expects to report in its 2011 fourth quarter results its estimate for pre-tax catastrophe losses from the severe flooding in Thailand of approximately $25 million to $35 million, net of reinsurance and reinstatement premiums.

In reaching this estimate, the Company has relied on information currently available from portfolio modeling, assessments of the exposures insured under individual policies and industry loss estimates. Due to the preliminary nature of the information used to determine this estimate, the ultimate cost to the Company from this event may differ materially from the foregoing estimate.

ABOUT ARGO GROUP INTERNATIONAL HOLDINGS, LTD.

Argo Group International Holdings, Ltd. (NasdaqGS: AGII) is an international underwriter of specialty insurance and reinsurance products in the property and casualty market. Argo Group offers a full line of products and services designed to meet the unique coverage and claims handling needs of businesses in four primary segments: Excess & Surplus Lines, Commercial Specialty, International Specialty and Syndicate 1200. Argo Group's insurance subsidiaries are A. M. Best-rated 'A' (Excellent) (third highest rating out of 16 rating classifications) with a stable outlook, and Argo's U.S. insurance subsidiaries are Standard and Poor's-rated 'A-' (Strong) with a stable outlook. More information on Argo Group and its subsidiaries is available at www.argolimited.com.

FORWARD-LOOKING STATEMENTS

This press release contains certain statements that are "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, as amended. Such statements are qualified by the inherent risks and uncertainties surrounding future expectations generally and also may differ materially from actual future experience involving any one or more of such statements. For a more detailed discussion of such risks and uncertainties, see Argo Group's filings with the SEC. The inclusion of a forward-looking statement herein should not be regarded as a representation by Argo Group that Argo Group's objectives will be achieved. Argo Group undertakes no obligation to publicly update forward-looking statements, whether as a result of new information, future events or otherwise.

Argo Group International Holdings, Ltd.
Matt Coyle, VP, Investor Relations, 617-235-6147
or
Jay Bullock, Chief Financial Officer, 441-278-3727