8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of report (Date of earliest event reported): August 26, 2005

Aon Corporation

(Exact Name of Registrant as Specified in Charter)

Delaware	1-7933	36-3051915
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)
200 East Randolph Street, Chicago, Illinois		60601
(Address of Principal Executive Offices)		(Zip Code)

Registrant’s telephone number, including area code: (312) 381-1000

Not Applicable
(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

oWritten communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

oSoliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

oPre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

oPre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01.  Other Events.

On August 26, 2005, Aon Corporation (“Aon”) issued a press release (the “Press Release”) announcing that Patrick G. Ryan, Aon’s Executive Chairman, adopted a 10b5-1 stock trading plan.  The plan permits the sale of up to 5 million shares of Aon common stock over a period of twelve months.

A copy of the Press Release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01. Financial Statements and Exhibits.

(a)—(b)	Not applicable.
(c)	Exhibits:

Exhibit Number	Description of Exhibit
99.1	Press Release issued by Aon Corporation on August 26, 2005.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	Aon CORPORATION
	By:	/s/ David P. Bolger
		David P. Bolger
		Executive Vice President, Chief Financial Officer and Chief Administrative Officer
Date: August 26, 2005

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EXHIBIT INDEX

Exhibit Number	Description of Exhibit
99.1	Press Release issued by Aon Corporation on August 26, 2005.

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EX-99.1

Exhibit 99.1

News from Aon

For Immediate Release

Aon Releases Statement of Patrick G. Ryan

CHICAGO, IL – August 26, 2005 –Aon Corporation (NYSE: AOC) today released the following statement of Patrick G. Ryan:

“During my 42 years as CEO, I have not sold any of my Aon stock, though I have gifted a certain portion of my holdings to charities, my family and trusts.  Having just celebrated my 68^th birthday, however, the time has come for me to address certain personal estate, charitable and other financial matters.  Accordingly, I am putting in place a 10b5-1 plan under which I will sell a portion of my Aon stock over the course of the next year.  The plan covers 5 million shares out of my total beneficial holdings of nearly 26 million shares.  As Aon’s Chairman, I have great faith in our management team under the leadership of our new CEO, Greg Case, and after this sale is complete, my wife and I will remain the Company’s largest individual shareholders and among its largest shareholders of any kind.”

Aon Corporation (www.aon.com) is a leading provider of risk management services, insurance and reinsurance brokerage, human capital and management consulting, and specialty insurance underwriting.  There are 47,000 employees working in Aon’s 500 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.

This press release contains certain statements related to future results, or states our intentions, beliefs and expectations or predictions for the future which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results depending on a variety of factors. Potential factors that could impact results include: general economic conditions in different countries in which we do business around the world, changes in global equity and fixed income markets that could affect the return on invested assets, fluctuations in exchange and interest rates that could influence revenue and expense, rating agency actions that could affect our ability to borrow funds, funding of our various pension plans, changes in the competitive environment, our ability to implement restructuring initiatives and other initiatives intended to yield cost savings, changes in commercial property and casualty markets and commercial premium rates that could impact revenues, changes in revenues and earnings due to the elimination of contingent commissions, other uncertainties surrounding a new compensation model, the impact of investigations brought by state attorneys general, state insurance regulators, federal prosecutors, and federal regulators, the impact of class actions and individual lawsuits including client class actions, securities class actions, derivative actions, and ERISA class actions, the cost of resolution of other contingent liabilities and loss contingencies, and the difference in ultimate paid claims in our underwriting companies from actuarial estimates.  Further information concerning the Company and its

business, including factors that potentially could materially affect the Company’s financial results, is contained in the Company’s filings with the Securities and Exchange Commission.

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Investor Contact:  Craig Streem
	Corporate Vice President, Investor Relations
	312-381-3983
Media Contact:     Al Orendorff
	Director, Public Relations
	312-381-3153