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                                    Exhibit (4)-25
                                    Commonwealth Edison Company
                                    Form 10-K File No. 1-1839


                   [Commonwealth Edison Company Letterhead]



As of September 28, 1997


To each of the Banks party to the
Credit Agreement referred to below

Ladies and Gentlemen:

We refer to the $200 million Credit Agreement dated as of October 1, 1991, as
amended (the "Credit Agreement"), among the undersigned, the Banks (including
you) named therein and the other Lenders from time to time parties thereto, and
Citibank, N.A., as Agent. Capitalized terms used herein without definition shall
have the meanings ascribed thereto in the Credit Agreement.

We are writing to request that you extend the expiration date of your Commitment
under the Credit Agreement from September 29, 1997 until September 28, 1998. If
you agree to this extension, all terms and conditions of the credit Agreement
would continue in effect during the period of such extension, except for the
following amendments: (a) the date "September 28, 1998," would be inserted in
lieu of the date "September 29, 1997," in clause (i) of the definition of
"Termination Date" in section 1.01 of the Credit Agreement, (b) the rate of
".125% per annum" would be inserted in lieu of the rate of ".15% per annum" in
Section 2.04 (a) of the Credit Agreement, (0.125% is the rate per annum
currently in effect), (c) the terms "Banks" and "Lenders" shall mean each of the
banks or other lending institutions agreeing to extend the expiration date of
its Commitment under the Credit Agreement or, if not presently a party to the
Credit Agreement, agreeing to become a party thereto on or after September 29,
1997, and (d) no additional fees would be payable under Section 2.04 (b) of the
Credit Agreement in respect of such extension. Such extension would become
effective as of September 29, 1997.

On and after the effective date of the extension requested herein and the
related amendments referred to above, each reference in the Credit Agreement to
"this Agreement", "hereunder", "hereof", or words of like import referring to
the Credit Agreement, and each reference in the other Loan Documents to "the
Credit Agreement", "thereunder", "thereof", or words of like import referring to
the Credit Agreement, shall mean and be a reference to the Credit Agreement as
amended by this letter.
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If you agree to extend the expiration of your Commitment and to the related
amendments provided above, please evidence such agreement by executing
and
returning at least two counterparts of this letter to the Agent at its address
at 399 Park Avenue, 11th Floor, Zone 19, New York, New York 10043, Attention of
Anita J. Brickell, no later than September 12, 1997.

On September 29, 1997, (i) the Commitment of each Bank which fails to return
executed counterparts of this letter as provided above shall automatically
terminate as presently provided in the Credit Agreement, and (ii) all
outstanding Advances of such Bank, together with all accrued interest thereon
and other amounts payable under the Credit Agreement with respect thereto, shall
become due and payable.


Very truly yours,

COMMONWEALTH EDISON COMPANY



By:
   ----------------------------
   John C. Bukovski
   Vice President


Agreed as of the date
first above written:

-------------------------------
(Name of Bank)


By:
   ----------------------------
   Name:
   Title: