Exhibit 15



Board of Directors and Stockholders
Aon Corporation


We are aware of the incorporation by reference in the Registration Statements of
Aon Corporation ("Aon") described in the following table of our report dated
November 2, 1995 relating to the unaudited condensed consolidated interim
financial statements of Aon Corporation that are included in its Form 10-Q for
the quarter ended September 30, 1995:



    Registration Statement
    ----------------------
     Form     Number                             Purpose
     ----     ------                             -------
                    
 
     S-8      2-79114     Pertaining to Aon's stock option plan
     S-8      2-82791     Pertaining to Aon's stock option plan
     S-8      33-27984    Pertaining to Aon's savings plan
     S-8      33-42575    Pertaining to Aon's stock award plan and stock option plan
     S-8      33-59037    Pertaining to Aon's stock award plan and stock option plan
     S-3      33-57562    Registration of Aon's 8% cumulative perpetual preferred stock 
                           and 6 1/4% cumulative convertible exchangeable preferred 
                           stock


Pursuant to Rule 436(c) of the Securities Act of 1933, our report is not a part
of the registration statements prepared or certified by accountants within the
meaning of Section 7 or 11 of the Securities Act of 1933.


                                     /s/ Ernst & Young LLP
                                     ERNST & YOUNG LLP


Chicago, Illinois
November 2, 1995


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