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Exhibit 10-3 FIRST AMENDMENT TO CREDIT AGREEMENT THIS FIRST AMENDMENT (this Amendment), dated as of July 16, 2004
amends the Three Year Credit Agreement dated as of October 31, 2003 (the
Credit Agreement) among EXELON CORPORATION, COMMONWEALTH EDISON
COMPANY, PECO ENERGY COMPANY, EXELON GENERATION COMPANY, LLC (collectively, the
Borrowers), various financial institutions and BANK ONE, NA, as
administrative agent (the Administrative Agent). Capitalized terms
used but not defined herein have the respective meanings given to them in the
Credit Agreement. WHEREAS, the Borrowers have requested certain amendments to the Credit
Agreement; NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration (the receipt and sufficiency of which are hereby
acknowledged), the parties hereto agree as follows: SECTION 1 AMENDMENTS. Upon the effectiveness of this Amendment
pursuant to Section 3, the Credit Agreement shall be amended as follows: 1.1 Amendment to Cover Page. The cover page is amended by deleting
the reference to $750,000,000. 1.2 Amendments to Definitions: SECTION 1.2.1 The following definitions in Section 1.01 are amended
to read in their entirety as follows: ComEd Sublimit means $50,000,000, subject to
adjustment as provided in Section 2.04(c). Exelon Sublimit means $100,000,000, subject to
adjustment as provided in Section 2.04(c). Genco Sublimit means $200,000,000, subject to
adjustment as provided in Section 2.04(c). Letter of Credit Sublimit means $400,000,000. Net Interest Expense means, for any Borrower for
any period, the total of (a) such Borrowers Interest Expense
for such period minus (b) to the extent that such
Interest Expense to Affiliates is included in Interest Expense
and relates to interest payments on debt obligations that are
subordinated to the obligations of such Borrower under this
Agreement, such Borrowers Interest Expense to Affiliates for
such period, minus (c) such Borrowers Transitional
Funding Instrument Interest for such period minus (d) in
the case of Exelon and Genco, interest on Sithe Project Debt for
such period.




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PECO Sublimit means $150,000,000, subject to
adjustment as provided in Section 2.04(c). SECTION 1.2.2 The last sentence of the definition of Commodity
Trading Obligations in Section 1.01 is amended to read in its entirety
as follows: The term commodities shall include electric energy and/or
capacity, coal, petroleum, natural gas, emissions allowances, weather
derivatives and related products and by-products and ancillary services. SECTION 1.2.3 The definition of Distributions on Preferred
Securities in Section 1.01 is deleted. SECTION 1.2.4 The following definition is added to Section 1.01 in
alphabetical order: Interest Expense to Affiliates means, for any period, in
the case of Exelon, ComEd and PECO, Interest Expense to Affiliates as
shown on a consolidated statement of income of Exelon, ComEd and PECO, as
applicable, for such period; provided that for any fiscal quarter
ended prior to (y) in the case of ComEd, December 31, 2003 and (z) in the
case of PECO, June 30, 2003, Interest Expense to Affiliates shall mean,
Distributions on Preferred Securities as shown on a consolidated
statement of income of such Borrower for such period. 1.3 Amendment to Section 2.04(c). Section 2.04(c) is amended by
deleting the amount $500,000,000 therein and substituting $250,000,000
therefor. 1.4 Amendment to Section 2.16.3. Section 2.16.3 is amended by
inserting, immediately after the word ascertain in the parenthetical in the
third sentence, the phrase ; provided that the LC Issuer shall not
issue any Facility LC if the LC Issuer shall have received written notice
(which has not been rescinded) from the Administrative Agent or any Lender that
any applicable condition precedent to the issuance or modification of such
Facility LC has not been satisfied and, in fact, such condition precedent is
not satisfied at the requested time of issuance. 1.5 Amendment to Section 4.01(c). Section 4.01(c) is amended to
read in its entirety as follows: (c) No authorization or approval or other action by, and no notice
to or filing with, any governmental authority or regulatory body is
required for the due execution, delivery and performance by such Borrower
of this Agreement or any applicable Note, except an appropriate order or
orders of (i) the Securities and Exchange Commission under the Public
Utility Holding Company Act of 1935, (ii) in the case of ComEd, the
Illinois Commerce Commission under the Illinois Public Utilities Act and
(iii) in the case of PECO, the Pennsylvania Public Utilities Commission
under the Pennsylvania Public Utility Code, which order or orders have
been duly obtained and are (x) in full force and effect and (y)
sufficient for the purposes hereof. 2




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1.6 Amendment to Section 5.01. Section 5.01 is amended by deleting
the phrase any Lender has any Commitment to such Borrower hereunder after the
word or in the first sentence and inserting the phrase the Commitments to
such Borrower have not been irrevocably terminated therefor. 1.7 Amendment to Section 5.02. Section 5.02 is amended by deleting
the phrase any Lender has any Commitment to such Borrower hereunder after the
word or in the first sentence and inserting the phrase the Commitments to
such Borrower have not been irrevocably terminated therefor. 1.8 Amendment to Section 5.02(f)(ii). Clause (ii) of Section
5.02(f) is amended to read in its entirety as follows: (ii) ComEd relating to (A) the priority of payments on its
subordinated debt securities contained in the Indenture dated as of
September 1, 1995 between ComEd and Wilmington Trust Company, as trustee,
as amended and supplemented to the date hereof, or any other indenture
that has terms substantially similar to such Indenture and that relates
to the issuance of trust preferred securities, and (B) the priority
payment of dividends on any outstanding shares of its prior preferred
stock and preference stock as set forth in its Restated Articles of
Incorporation, as such Restated Articles of Incorporation are in effect
on the date hereof. 1.9 Amendment to Schedule II. Schedule II is amended in its
entirety by substituting the Schedule II attached hereto therefor. SECTION 2 CONDITIONS PRECEDENT. This Amendment shall become
effective when (i) the Administrative Agent has received counterpart signature
pages to this Amendment (by facsimile or otherwise) signed by the Borrowers and
the Majority Lenders and (ii) the Five Year Credit Agreement dated as of July
16, 2004 among the Borrowers, various financial institutions and Bank One, NA,
as agent, has become effective. SECTION 3 MISCELLANEOUS. 3.1 Continuing Effectiveness, etc. Except as expressly set forth
herein, the Credit Agreement shall remain in full force and effect and is
ratified, approved and confirmed in all respects. 3.2 Severability. Any provision of this Amendment which is
prohibited or unenforceable in any jurisdiction shall, as to such provision and
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions of this
Amendment or affecting the validity or enforceability of such provision in any
other jurisdiction. 3.3 Headings. The various headings of this Amendment are inserted
for convenience only and shall not affect the meaning or interpretation of this
Amendment. 3




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3.4 Execution in Counterparts. This Amendment may be executed by
the parties hereto in several counterparts, each of which shall be deemed to be
an original and all of which shall constitute together but one and the same
agreement. 3.5 Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY, AND
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE COMMONWEALTH OF PENNSYLVANIA. 3.6 Successors and Assigns. This Amendment shall be binding upon
and shall inure to the benefit of the parties hereto and their respective
successors and assigns. [SIGNATURES FOLLOW] 4




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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers as of the date first above written. EXELON CORPORATIONBy:Name:Title: COMMONWEALTH EDISON COMPANYBy:Name:Title: PECO ENERGY COMPANYBy:Name:Title: EXELON GENERATION COMPANY, LLCBy:Name:Title: First Amendment




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THE LENDERS BANK ONE, NA(Main Office Chicago), as Administrative Agent
and as a LenderBy:Name:Title: First Amendment




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BARCLAYS BANK PLC, as Syndication Agent and
as a LenderBy:Name:Title: First Amendment




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CITIBANK, N.A., as Co-Documentation Agent
and as a LenderBy:Name:Title: First Amendment




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WACHOVIA BANK, NATIONAL ASSOCIATION, as
Co-Documentation
Agent and as a LenderBy:Name:Title: First Amendment




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DRESDNER BANK AG, NEW YORK AND GRAND CAYMAN
BRANCHES, as Co-Documentation Agent and as a LenderBy:Name:Title: By:Name:Title: First Amendment




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ABN AMRO BANK, N.V.By:Name:Title: First Amendment




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BANK OF AMERICA, N.A.By:Name:Title: First Amendment




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JPMORGAN CHASE BANKBy:Name:Title: First Amendment




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KEYBANK NATIONAL ASSOCIATIONBy:Name:Title: First Amendment




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LEHMAN BROTHERS BANK, FSBBy:Name:Title: First Amendment




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MORGAN STANLEY BANKBy:Name:Title: First Amendment




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BNP PARIBASBy:Name:Title: By:Name:Title: First Amendment




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MERRILL LYNCH BANK USABy:Name:Title: First Amendment




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THE BANK OF NOVA SCOTIABy:Name:Title: First Amendment




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UBS LOAN FINANCE LLCBy:Name:Title: First Amendment




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THE NORTHERN TRUST COMPANYBy:Name:Title: First Amendment




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MELLON BANK, N.A.By:Name:Title: First Amendment




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CREDIT SUISSE FIRST BOSTONBy:Name:Title: First Amendment




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THE BANK OF NEW YORKBy:Name:Title: First Amendment




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MIZUHO CORPORATE BANK, LTD.By:Name:Title: First Amendment




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U.S. BANK NATIONAL ASSOCIATIONBy:Name:Title: First Amendment




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WELLS FARGO BANK, N.A.By:Name:Title: First Amendment




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FIFTH THIRD BANKBy:Name:Title: First Amendment




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BANK HAPOALIMBy:Name:Title: First Amendment




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SCHEDULE II
COMMITMENTS LENDER
    
    COMMITMENTBank One, NA
    
    $
    30,666,666.67Barclays Bank PLC
    
    $
    30,666,666.67Wachovia Bank, National Association
    
    $
    29,166,666.66Dresdner Bank, AG New York and Grand Cayman Branches
    
    $
    29,166,666.66Citibank, N.A.
    
    $
    29,166,666.66ABN AMRO Bank, N.V.
    
    $
    29,166,666.66Bank of America, N.A.
    
    $
    24,666,666.67BNP Paribas
    
    $
    24,666,666.67JPMorgan Chase Bank
    
    $
    24,666,666.67KeyBank National Association
    
    $
    24,666,666.67Merrill Lynch Bank USA
    
    $
    24,666,666.67Morgan Stanley Bank
    
    $
    24,666,666.67The Bank of Nova Scotia
    
    $
    24,666,666.67UBS Loan Finance LLC
    
    $
    24,666,666.67Credit Suisse First Boston
    
    $
    18,333,333.33Mellon Bank, N.A.
    
    $
    15,000,000.00The Bank of New York
    
    $
    15,000,000.00The Northern Trust Company
    
    $
    15,000,000.00Lehman Brothers Bank, FSB
    
    $
    14,666,666.67Bank Hapoalim
    
    $
    10,000,000.00Mizuho Corporate Bank, Ltd.
    
    $
    10,000,000.00U.S. Bank National Association
    
    $
    10,000,000.00Wells Fargo Bank, N.A.
    
    $
    10,000,000.00Fifth Third Bank
    
    $
    6,666,666.66TOTAL
    
    $
    500,000,000