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Exhibit 12(b)

Aon Corporation and Consolidated Subsidiaries
Combined With Unconsolidated Subsidiaries
Computation of Ratio of Earnings to Combined Fixed Charges
and Preferred Stock Dividends

			Six Months Ended June 30,				Years Ended December 31,
			2003		2002		2002		2001		2000		1999		1998
			(millions except ratios)
Income before provision for income taxes and minority interest			$	501	$	287	$	793	$	309	$	854	$	635	$	931
Add back fixed charges:
	Interest on indebtedness			55		59		124		127		140		105		87
	Interest credited on investment-type insurance contracts			2		21		29		56		71		77		72
	Interest on ESOP			—		—		—		—		—		1		2
	Portion of rents representative of interest factor			27		28		59		57		54		49		51
		Income as adjusted	$	585	$	395	$	1,005	$	549	$	1,119	$	867	$	1,143
Fixed charges and preferred stock dividends:
	Interest on indebtedness		$	55	$	59	$	124	$	127	$	140	$	105	$	87
	Preferred stock dividends			31		35		58		70		70		70		70
		Interest and dividends		86		94		182		197		210		175		157
	Interest credited on investment-type insurance contracts			2		21		29		56		71		77		72
	Interest on ESOP			—		—		—		—		—		1		2
	Portion of rents representative of interest factor			27		28		59		57		54		49		51
		Total fixed charges and preferred stock dividends	$	115	$	143	$	270	$	310	$	335	$	302	$	282
Ratio of earnings to combined fixed charges and preferred stock dividends(1)				5.1		2.8		3.7		1.8		3.3		2.9		4.1

(1)

Included in total fixed charges and preferred stock dividends are $29 million and $33 million for the six months ended June 30, 2003 and 2002, respectively, $54 million for the year ended December 31, 2002 and $66 million for the years ended December 31, 2001, 2000, 1999 and 1998, of pretax distributions on the 8.205% mandatorily redeemable preferred capital securities which are classified as "minority interest" on the condensed consolidated statements of income.

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Exhibit 12(b)

Aon Corporation and Consolidated Subsidiaries Combined With Unconsolidated Subsidiaries Computation of Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends