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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

			Three Months Ended March 31,
							Years Ended December 31,
(millions except ratios)
			2003		2002		2002		2001		2000		1999		1998
Income before provision for income taxes and minority interest			$	256	$	271	$	793	$	309	$	854	$	635	$	931
Add back fixed charges:
	Interest on indebtedness			28		29		124		127		140		105		87
	Interest credited on investment-type insurance contracts			1		12		29		56		71		77		72
	Interest on ESOP			—		—		—		—		—		1		2
	Portion of rents representative of interest factor			14		15		59		57		54		49		51
		Income as adjusted	$	299	$	327	$	1,005	$	549	$	1,119	$	867	$	1,143
Fixed charges and preferred stock dividends:
	Interest on indebtedness		$	28	$	29	$	124	$	127	$	140	$	105	$	87
	Preferred stock dividends			15		17		58		70		70		70		70
		Interest and dividends		43		46		182		197		210		175		157
	Interest credited on investment-type insurance contracts			1		12		29		56		71		77		72
	Interest on ESOP			—		—		—		—		—		1		2
	Portion of rents representative of interest factor			14		15		59		57		54		49		51
		Total fixed charges and preferred stock dividends	$	58	$	73	$	270	$	310	$	335	$	302	$	282
Ratio of earnings to combined fixed charges and preferred stock dividends (1)				5.2		4.5		3.7		1.8		3.3		2.9		4.1

(1)

Included in total fixed charges and preferred stock dividends are $14 million and $16 million for the three months ended March 31, 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