EXHIBIT 12.1

Ameren Corporation

Computation of Ratio of Earnings to Fixed Charges

(Thousands of Dollars, Except Ratios)

	Year Ended December 31,
	2008		2009		2010		(a)	2011		(b)	2012
Earnings available for fixed charges, as defined:
Net income from continuing operations attributable to Ameren Corporation	$	181,189	$	367,827	$	483,414		$	417,596		$	517,398
Tax expense (benefit) based on income	128,160		154,369		273,927			245,191			308,590
Fixed charges excluding preferred stock dividends tax adjustment (c)	393,395		465,523		458,490			427,593			422,264
Earnings available for fixed charges, as defined	$	702,744	$	987,719	$	1,215,831		$	1,090,380		$	1,248,252
Fixed charges, as defined:
Interest expense on short-term and long-term debt  (c)	$	359,414	$	427,663	$	426,666		$	397,618		$	389,496
Estimated interest cost within rental expense	5,331		7,211		7,476			7,193			7,024
Amortization of net debt premium, discount, and expenses	18,293		20,775		16,070			16,754			19,301
Subsidiary preferred stock dividends	10,357		9,874		8,278			6,028			6,443
Adjust preferred stock dividends to pretax basis	6,989		6,279		4,942			3,859			4,032
Total fixed charges, as defined	$	400,384	$	471,802	$	463,432		$	431,452		$	426,296
Consolidated ratio of earnings to fixed charges	1.76		2.09		2.62			2.53			2.93

(a) In 2010, Ameren Corporation recorded an impairment charge of $64 million related to the Meredosia energy center. See Note 17 - Impairment and Other Charges under Exhibit 99.4, Item 8 of this current report on Form 8-K for additional information.

(b) In 2011, Ameren Corporation recorded a charge to earnings of $123 million related to an Ameren Missouri loss on regulatory disallowance and charges related to the closure of the Meredosia and Hutsonville energy centers. See Note 17 - Impairment and Other Charges under Exhibit 99.4, Item 8 of this current report on Form 8-K for additional information.

(c) Includes interest expense related to uncertain tax positions.