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Exhibit 12.3

Ameren Illinois Company
Computation of Ratio of Earnings to Fixed Charges and Combined
Fixed Charges and Preferred Stock Dividend Requirements
(in millions, except ratios)

	Year Ended December 31,										Nine Months Ended September 30, 2017
	2012		2013		2014		2015		2016
Earnings available for fixed charges, as defined:
Net income from continuing operations	$	144	$	163	$	204	$	217	$	255	$	193
Tax expense based on income		94		110		143		127		158		127
Fixed charges(a)		130		132		124		136		143		111
Earnings available for fixed charges, as defined	$	368	$	405	$	471	$	480	$	556	$	431
Fixed charges, as defined:
Interest expense on short-term and long-term debt(a)	$	119	$	117	$	111	$	122	$	129		101
Estimated interest cost within rental expense		—		—		—		—		—		—
Amortization of net debt premium, discount, and expenses		11		15		13		14		14		10
Total fixed charges, as defined	$	130	$	132	$	124	$	136	$	143	$	111
Ratio of earnings to fixed charges		2.8		3.1		3.8		3.5		3.9		3.9
Earnings required for combined fixed charges and preferred stock dividends:
Preferred stock dividends	$	3	$	3	$	3	$	3	$	3		2
Adjustment to pretax basis		2		2		2		2		2		1
	$	5	$	5	$	5	$	5	$	5		3
Combined fixed charges and preferred stock dividend requirements	$	135	$	137	$	129	$	141	$	148	$	114
Ratio of earnings to combined fixed charges and preferred stock dividend requirements		2.7		3.0		3.7		3.4		3.8		3.8

(a)

Includes net interest related to uncertain tax positions.

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Exhibit 12.3

Ameren Illinois Company Computation of Ratio of Earnings to Fixed Charges and Combined Fixed Charges and Preferred Stock Dividend Requirements (in millions, except ratios)