CHICAGO, IL, October 22, 2008 – Aon Corporation (NYSE: AOC) plans to announce third quarter 2008 results on Friday, October 31, 2008 in a news release to be issued before the market opens.  Greg Case, president and CEO will host a conference call at 7:30 am Central Time on October 31.  The conference call will be broadcast live through Aon’s website at www.aon.com. Windows Media Player is required to listen to this webcast. A replay will be available shortly after the live webcast.  The earnings release will be available on Aon’s web site at www.aon.com. 

About Aon
Aon Corporation (NYSE: AOC) is the leading global provider of risk management services, insurance and reinsurance brokerage, human capital and management consulting. Through its 36,000 colleagues worldwide, Aon readily delivers distinctive client value via innovative and effective risk management and workforce productivity solutions. Our industry-leading global resources, technical expertise and industry knowledge are delivered locally through more than 500 offices in more than 120 countries. Aon was named the world's best broker by Euromoney magazine's 2008 Insurance Survey. In 2008, Aon ranked highest on the Business Insurance ranking of the world's largest insurance brokers based on commercial retail, wholesale, reinsurance and personal lines brokerage revenues. Aon also was ranked by A.M. Best as the number one insurance broker based on brokerage revenues in 2007 and 2008, and was voted best insurance intermediary, best reinsurance intermediary, and best employee benefits consulting firm in 2007 and 2008 by the readers of Business Insurance. For more information on Aon, log onto http://www.aon.com/.

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