Exhibit 12.3

Commonwealth Edison Company

Ratio of Earnings to Fixed Charges

	Years Ended December 31,
	2011			2012			2013			2014			2015
Pre-tax income from continuing operations		666			618			401			676			706
Plus: Loss from equity investees		—			—			—			—
Less:Capitalized interest		(4	)		(3	)		(5	)		(2	)		(4	)
Pre-tax income from continuing operations after adjustment for income or loss from equity investees and capitalized interest		662			615			396			674			702
Fixed Charges:
Interest expensed and capitalized, amortization of debt discount and premium on all indebtedness		330			297			575			311			331
Interest component of rental expense (a)		6			6			5			5			4
Total fixed charges		336			303			580			316			335
Pre-tax income from continuing operations after adjustment for income or loss from equity investees, capitalized interest plus fixed charges		998			918			976			990			1,037
Ratio of earnings to fixed charges		3.0			3.0			1.7			3.1			3.1

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