Exhibit 12.3

Commonwealth Edison Company

Ratio of Earnings to Fixed Charges

	Years Ended December 31,
	2012			2013			2014			2015			2016
Pre-tax income from continuing operations		618			401			676			706			679
Less:Capitalized interest		(3	)		(5	)		(2	)		(4	)		(8	)
Pre-tax income from continuing operations after adjustment for income or loss from equity investees and capitalized interest		615			396			674			702			671
Fixed Charges:
Interest expensed and capitalized, amortization of debt discount and premium on all indebtedness		297			575			311			331			465
Interest component of rental expense (a)		6			5			5			4			5
Total fixed charges		303			580			316			335			470
Pre-tax income from continuing operations after adjustment for income or loss from equity investees, capitalized interest plus fixed charges		918			976			990			1,037			1,141
Ratio of earnings to fixed charges		3.0			1.7			3.1			3.1			2.4

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