Exhibit 12.3

Commonwealth Edison Company

Ratio of Earnings to Fixed Charges

	Years Ended December 31,
	2010			2011			2012			2013			2014
Pre-tax income from continuing operations		693			666			618			401			676
Plus: Loss from equity investees		—			—			—			—			—
Less:Capitalized interest		(2	)		(4	)		(3	)		(5	)		(2	)
Pre-tax income from continuing operations after adjustment for income or loss from equity investees and capitalized interest		691			662			615			396			674
Fixed Charges:
Interest expensed and capitalized, amortization of debt discount and premium on all indebtedness		368			330			297			575			311
Interest component of rental expense (a)		6			6			6			5			5
Total fixed charges		374			336			303			580			316
Pre-tax income from continuing operations after adjustment for income or loss from equity investees, capitalized interest plus fixed charges		1,065			998			918			976			990
Ratio of earnings to fixed charges		2.8			3.0			3.0			1.7			3.1

(a) Represents one-third of rental expense relating to operating leases, which is a reasonable approximation of the interest factor.