News from Aon

For Immediate Release

Aon Declares Quarterly Dividend

CHICAGO, IL - October 7, 2011 - Aon Corporation (NYSE: AON) today announced that the Board of Directors has declared a quarterly cash dividend of $0.15 per share on outstanding common stock. The dividend is payable on November 15, 2011 to stockholders of record on
November 1, 2011.

About Aon
Aon Corporation (NYSE:AON) is the leading global provider of risk management services, insurance and reinsurance brokerage, and human resources solutions and outsourcing. Through its more than 59,000 colleagues worldwide, Aon unites to deliver distinctive client value via innovative and effective risk management and workforce productivity solutions. Aon's industry-leading global resources and technical expertise are delivered locally in over 120 countries. Named the world's best broker by Euromoney magazine's 2008, 2009 and 2010 Insurance Survey, Aon also ranked highest on Business Insurance's listing of the world's insurance brokers based on commercial retail, wholesale, reinsurance and personal lines brokerage revenues in 2008 and 2009. A.M. Best deemed Aon the number one insurance broker based on revenues in 2007, 2008 and 2009, and Aon was voted best insurance intermediary 2007-2010, best reinsurance intermediary 2006-2010, best captives manager 2009-2010, and best employee benefits consulting firm 2007-2009 by the readers of Business Insurance. Visit http://www.aon.com for more information on Aon and http://www.aon.com/manchesterunited to learn about Aon's global partnership and shirt sponsorship with Manchester United.

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