Exhibit 99-1

Certificate Pursuant to Section 1350 of Chapter 63 of Title 18 United States
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         The undersigned officer hereby certifies, as to the Quarterly Report on
Form 10-Q of Exelon Corporation for the quarterly period ended March 31, 2003,
that (i) the report fully complies with the requirements of section 13(a) or
15(d) of the Securities Exchange Act of 1934, and (ii) the information contained
in the report fairly presents, in all material respects, the financial condition
and results of operations of Exelon Corporation.


Date:  May 2, 2003                       /s/ John W. Rowe
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                                         John W. Rowe
                                         Chairman, President and
                                         Chief Executive Officer