Press Release

Ambac Financial Group, Inc. Conference Call to Discuss Second Quarter Earnings Set for August 6, 2008 at 8:30 A.M. EST.

NEW YORK, July 21, 2008 -- Ambac Financial Group, Inc. (NYSE: ABK) (Ambac) announced that it will host a conference call for investors on August 6 at 8:30 a.m. Eastern to discuss second quarter 2008 earnings which are scheduled to be released at 6 a.m. that morning. The dial in number for the call is 877-407-0778 (U.S.) and 201-689-8565 (outside the U.S.).

The conference call will also be broadcast live on Ambac's web site at www.ambac.com.

Beginning at 2 p.m. on August 6 through August 20, the conference call will be available in replay. The replay numbers are 877-660-6853 (U.S.) and 201-612-7415 (outside the U.S.). The account and confirmation numbers for the replay are 286 and 291971, respectively. A recording will also be available on Ambac's web site approximately one hour after the end of the conference call.

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Ambac Financial Group, Inc., headquartered in New York City, is a holding company whose affiliates provide financial guarantees and financial services to clients in both the public and private sectors around the world. Ambac's principal operating subsidiary, Ambac Assurance Corporation, a guarantor of public finance and structured finance obligations, has earned a Aa3 rating from Moody's Investors Service, Inc. and a AA rating from Standard & Poor's Ratings Services; Moody's rating is on negative outlook while Standard & Poor's maintains a credit watch negative. Ambac Financial Group, Inc. common stock is listed on the New York Stock Exchange (ticker symbol ABK).

Contact Information:

Investor/Media Contact: Vandana Sharma
212- 208-3333
vsharma@ambac.com

Fixed Income Contact: Peter Poillon
(212) 208-3222
ppoillon@ambac.com