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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)
			2004		2003		2003		2002		2001			2000		1999
Income from continuing operations before provision for income taxes and minority interest			$	300	$	268	$	1,132	$	840	$	369		$	850	$	625
Less: Earnings from unconsolidated entities under the equity method of accounting				17		7		49		19		(139	)		44		50
Add back fixed charges:
	Interest on indebtedness			34		28		101		124		127			140		105
	Interest credited on deposit-type insurance contracts			—		1		—		29		56			71		77
	Interest on ESOP			—		—		—		—		—			—		1
	Portion of rents representative of interest factor			15		14		67		59		57			54		49
		Income as adjusted	$	332	$	304	$	1,251	$	1,033	$	748		$	1,071	$	807
Fixed charges and preferred stock dividends:
	Interest on indebtedness(1)		$	34	$	28	$	101	$	124	$	127		$	140	$	105
	Preferred stock dividends(2)			1		15		61		58		70			70		70
		Interest and dividends		35		43		162		182		197			210		175
	Interest credited on deposit-type insurance contracts			—		1		—		29		56			71		77
	Interest on ESOP			—		—		—		—		—			—		1
	Portion of rents representative of interest factor			15		14		67		59		57			54		49
		Total fixed charges and preferred stock dividends	$	50	$	58	$	229	$	270	$	310		$	335	$	302
Ratio of earnings to combined fixed charges and preferred stock dividends				6.6		5.2		5.5		3.8		2.4			3.2		2.7

(1)

As a result of the adoption of FIN 46 on December 31, 2003, Aon was required to deconsolidate its 8.205% mandatorily redeemable preferred capital securities (capital securities). This decrease was offset by an increase in notes payable. Beginning in 2004, interest expense ($14 million for the three months ended March 31, 2004) on these notes payable is reported as part of interest expense on the condensed consolidated statements of income.

(2)

Included in preferred stock dividends are $15 million for the three months ended ended March 31, 2003, $57 million and $54 million for the years ended December 31, 2003 and 2002, respectively, and $66 million for the years ended December 31, 2001, 2000 and 1999 of pretax distributions on the capital securities which are classified as "minority interest" on the condensed consolidated statements of income.

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Exhibit 12(b)