Exhibit 12.3

Ameren Illinois Company

Computation of Ratio of Earnings to Fixed Charges and Combined

Fixed Charges and Preferred Stock Dividend Requirements

(Thousands of Dollars, Except Ratios)

	Year Ended December 31,
	2007		2008		2009		2010(a)		2011
Net income from continuing operations	$	56,011	$	40,713	$	133,360	$	212,547	$	195,731
Add- Taxes based on income		26,571		15,866		78,970		136,614		126,821
Net income before income taxes		82,582		56,579		212,330		349,161		322,552
Add- fixed charges:
Interest on short-term and long-term debt (b)		131,826		140,289		163,831		152,667		132,493
Estimated interest cost within rental expense		1,476		1,890		3,797		3,899		3,581
Amortization of net debt premium, discount, and expenses		10,624		11,058		6,317		5,250		5,234
Total fixed charges		143,926		153,237		173,945		161,816		141,308
Earnings available for fixed charges		226,508		209,816		386,275		510,977		463,860
Ratio of earnings to fixed charges		1.57		1.36		2.22		3.15		3.28
Earnings required for combined fixed charges and preferred stock dividends:
Preferred stock dividends		6,656		6,160		5,678		4,435		3,045
Adjustment to pretax basis		3,158		2,401		3,362		2,396		1,973
		9,814		8,561		9,040		6,831		5,018
Combined fixed charges and preferred stock dividend requirements	$	153,740	$	161,798	$	182,985	$	168,647	$	146,326
Ratio of earnings to combined fixed charges and preferred stock dividend requirements		1.47		1.29		2.11		3.02		3.17

^(a)  Effective October 1, 2010, Central Illinois Light Company and Illinois Power Company merged with and into Central Illinois Public Service Company, with the surviving corporation renamed Ameren Illinois Company. In accordance with authoritative guidance, periods presented reflect the combined results for continuing operations. See Note 1 - Summary of Significant Accounting Policies of this Form 10-K for additional information.

^(b)  Includes interest expense related to uncertain tax positons