21.01.2005 – 23:43

Aon Dividend Announcement

Chicago (ots/PRNewswire)

Aon Corporation (NYSE: AOC) today
declared a quarterly cash dividend of US$0.15 per common share. The
cash dividend is payable on February 16, 2005  to common stockholders
of record at the close of business on February 3,  2005.

(Logo: http://www.newscom.com/cgi-bin/prnh/20041215/CGW049LOGO )

Aon Corporation ( http://www.aon.com ) is a leading provider of
risk management services, insurance and reinsurance brokerage, human
capital and management consulting, and specialty insurance
underwriting. The company employs approximately 51,000 professionals
in its 600 offices in more than 120 countries. Backed by broad
resources, industry knowledge and technical expertise, Aon
professionals help a wide range of clients develop effective risk
management and workforce productivity solutions.

Investor Contact: Craig Streem
                      Corporate Vice President, Investor Relations
                      +1-312-381-3983
    Media Contact:    Dave Van de Walle
                      Aon Corporation, Public Relations
                      +1-312-381-5028
                       dave_vandewalle@aon.com

Web site: http://www.aon.com

Contact:

Investor, Craig Streem, Corporate Vice President, Investor Relations,
+1-312-381-3983, or Media, Dave Van de Walle, Public Relations,
+1-312-381-5028, dave_vandewalle@aon.com , both of Aon Corporation;
Photo: http://www.newscom.com/cgi-bin/prnh/20041215/CGW049LOGO; AP
Archive: http://photoarchive.ap.org; PRN Photo Desk,
photodesk@prnewswire.com

Aon Dividend Announcement

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