Exhibit 12.3

Ameren Illinois Company

Computation of Ratio of Earnings to Fixed Charges and Combined

Fixed Charges and Preferred Stock Dividend Requirements

(Millions of Dollars, Except Ratios)

	Three Months Ended March 31,
	2018
Earnings available for fixed charges, as defined:
Net income	$	96
Tax expense based on income	32
Fixed charges	38
Earnings available for fixed charges, as defined	$	166
Fixed charges, as defined:
Interest expense on short-term and long-term debt	$	35
Amortization of net debt premium, discount, and expenses	3
Total fixed charges, as defined	$	38
Ratio of earnings to fixed charges	4.4
Earnings required for combined fixed charges and preferred stock dividends:
Preferred stock dividends	$	1
Adjustment to pretax basis	—
	$	1
Combined fixed charges and preferred stock dividend requirements	$	39
Ratio of earnings to combined fixed charges and preferred stock dividend requirements	4.3