UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

November 6, 2015

Date of Report (Date of earliest event reported)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Explanatory Statement

On November 6, 2015, Exelon Corporation (Exelon) and Baltimore Gas and Electric Company (BGE) filed a Current Report on Form 8-K to report the filing of an application with the Maryland Public Service Commission seeking increases of $135.2 million and $77.8 million to its electric and gas distribution rate bases, respectively (the “Original Report”). Exelon and BGE are filing this Form 8-K/A as an amendment to the Original Report to correct Item 8.01 of the Original Report which reported the requested rates of return on rate base instead of the requested rates of return on equity. The Original Report stated that the requested rates of return on equity in the application were 7.74% and 7.69% for electric and gas distribution, respectively. The correct requested rates of return on equity in the application are 10.6% and 10.5% for electric and gas distribution, respectively. All other information disclosed in the Original Report remains unchanged.

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This combined Form 8-K/A is being furnished separately by Exelon and BGE (Registrants). Information contained herein relating to any individual Registrant has been furnished by such Registrant on its own behalf. No Registrant makes any representation as to information relating to any other Registrant.

This Current Report includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks and uncertainties. The factors that could cause actual results to differ materially from these forward-looking statements include those discussed herein as well as those discussed in (1) Exelon’s 2014 Annual Report on Form 10-K in (a) ITEM 1A. Risk Factors, (b) ITEM 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations and (c) ITEM 8. Financial Statements and Supplementary Data: Note 22; (2) Exelon’s Third Quarter 2015 Quarterly Report on Form 10-Q in (a) Part II, Other Information, ITEM 1A. Risk Factors; (b) Part 1, Financial Information, ITEM 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations and (c) Part I, Financial Information, ITEM 1. Financial Statements: Note 19; and (3) other factors discussed in filings with the Securities and Exchange Commission by the Registrants. Readers are cautioned not to place undue reliance on these forward-looking statements, which apply only as of the date of this Current Report. None of the Registrants undertakes any obligation to publicly release any revision to its forward-looking statements to reflect events or circumstances after the date of this Current Report.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, each Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

November 6, 2015

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