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Exhibit 10.25

EDISON MISSION MIDWEST HOLDINGS AND SUBSIDIARIES
"MIDWEST"
TAX ALLOCATION AGREEMENT

        This TAX ALLOCATION AGREEMENT (this "Agreement") is made and entered
into as of January 1, 2002, by and among Edison Mission Midwest Holdings Co., a
Delaware corporation ("EMMH"), Midwest Generation, LLC, a Delaware limited
liability company ("MWG"), and Edison Mission Overseas Co., a Delaware
corporation ("EMO") (collectively, EMMH, MWG and EMO are referred to as the
"Midwest Subgroup," and individually referred to as "Subgroup Members").

RECITALS

A.The parties are each indirect subsidiaries of Edison Mission Energy, a
Delaware corporation ("EME") and an indirect wholly-owned subsidiary of Edison
International ("EIX").

B.The parties desire to provide for and confirm current practices for the
allocation, cash settlement and accounting of consolidated and combined federal
and state income tax liabilities among the parties comprising the Midwest
Subgroup.

C.The parties desire to have this Agreement address the computation of all tax
liabilities due and owing among the Subgroup Members after the date of this
Agreement with regard to taxable periods beginning on or after January 1, 2002,
as well as for computations for prior taxable periods.

D.It is the intent of EME to add Subgroup Members in the future as necessary in
response to changing business needs, which may be done by adding signature pages
as an addendum to this Agreement.

E.This Agreement shall not affect the nonconsolidated tax liabilities of any
Subgroup Member, which shall remain the separate obligation of each subsidiary.

AGREEMENT

        NOW, THEREFORE, in consideration of the promises and of the mutual
covenants herein contained and for other good and valuable consideration, the
receipt of which is hereby acknowledged, the parties hereto agree as follows:

        1.    Tax Liability Allocation and Computation.    

        a.    Federal Income Taxes.    For each taxable period to which this
Agreement is applicable, the consolidated federal income liability of the
Midwest Subgroup will be allocated to each Subgroup Member, consistent with the
method and principles of tax allocation described in Treas. Reg. sec.
1.1552-1(a)(2) ("Separate Return Method"), as modified in the manner described
in Treas. Reg. sec. 1.1502-33(d)(2)(i) ("Wait and See Method"). Each Subgroup
Member's allocated portion of the federal or state income tax liability as
computed under Sections 1a. and 1b. shall be referred to as the federal or state
tax "Separate Liability" of such Subgroup Member. The Subgroup Members shall
only be allocated tax benefits (from, but not limited to, losses, credits or
state apportionment) at the time and in the amount that each Subgroup Member
could have used the tax benefit had it filed a separate return (consistent with
the principles of the Wait and See Method). Each Subgroup Member's federal or
state income allocated tax benefit as computed under these Sections 1a. and 1b.
shall be referred to as the federal or state tax "Separate Benefit" of such
member of the Midwest Subgroup. In no event shall any Subgroup Member be
entitled to any cash payment for federal or state income tax benefits under this
Agreement.

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        b.    State Combined or Consolidated Taxes.    The same principles used
in Section 1a. above for federal income taxes shall be used to compute state
income tax allocations and liabilities for the Subgroup Members with respect to
any combined or consolidated state income return that the Midwest Subgroup is
included into with its Parent, except that the Separate Liability or Separate
Benefit allocation shall be computed using the long term state income tax
apportionment factors of the EIX consolidated tax group, and EME's determination
of such factor shall be conclusive. Nothing in this Agreement shall change the
sole responsibility of each Subgroup Member for its state income tax liabilities
and returns for separate income taxes required to be computed on a
nonconsolidated, noncombined basis. Any state tax liability or benefit not
allocable to a specific Subgroup Member under this Section 1b. shall be
allocated to EMMH.

        c.    Providing Information.    The Subgroup Members shall provide to
EME on a monthly basis, or upon demand by EME as necessary, all relevant
information necessary to calculate their federal and state tax liabilities and
payments for EME and subsidiaries and the Separate Liability or Separate Benefit
of the Subgroup Members.

        2.    Payments.    

        a.    In General.    For each taxable period for which this Agreement is
applicable, federal income tax or state combined or consolidated income tax
liabilities will be allocated at least quarterly in the manner outlined in
Section 1 above. Payments of federal or state tax liabilities by each Subgroup
Member shall be made of its allocated portion of the Midwest Subgroup tax
liability as computed under Section 1 above, net of any Separate Benefits
computed under Section 2b. below for such Subgroup, either by legal offset of
intercompany accounts or by payment in cash upon demand by EMMH, at the dates
payment is due under that certain Edison Mission Energy and Subsidiaries Tax
Allocation Agreement, dated as of even date herewith (the "EME and Subsidiaries
Tax Allocation Agreement"), provided that such payments are consistent with and
are not limited by debt financing restrictions and covenants.

        b.    Assignment of Separate Benefits.    For each taxable period for
which this Agreement is applicable, but not less than on an annual basis, any
allocated Separate Benefit, or rights to a future Separate Benefit under
Section 1a. shall be assigned, distributed or transferred by one Subgroup Member
to another in payment of interest or principal on intercompany subordinated
debt, whether or not the Separate Benefit is currently payable or allocable
under the "Wait and See" method described in Section 1a. above. Such
transactions may be undertaken as necessary to facilitate the legal offsetting
of intercompany payables or receivables for efficient administration of tax and
financial accounting.

        c.    Netting of Intercompany Tax Payables/Receivables.    From time to
time, but not less than on an annual basis, any Separate Liability or Separate
Benefit payable or receivable arising under this Agreement currently due,
recognized and owed within the Midwest Subgroup among Subgroup Members shall be
legally offset against one other, or against other intercompany payables or
receivables, to facilitate the efficient administration of tax and financial
accounting. Separate Benefits may be offset against Separate Liabilities whether
or not the Separate Benefit is currently payable or allocable under the "Wait
and See" method described in Section 1a. above.

        3.    Reconciliation of Tax Liability.    The Subgroup Members shall be
allocated, and pay either by legal offset of intercompany accounts or by payment
in cash upon demand by EMMH under terms described in Section 2, any additional
Separate Liability due, or receive credit against allocated Separate Liabilities
for any overpayment, on the same date that EMMH makes or receives any payments
under Section 2 of the Edison Mission Energy Subgroup Tax Allocation Agreement,
dated as of even date herewith, provided that any such payments are consistent
with and are not limited by debt financing restrictions and covenants.

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        4.    Adjustments to Tax Liability.    If any adjustments are made to
the income, gains, losses, deductions or credits pertaining to EME or any of its
subsidiaries, as reported in a federal or state combined/consolidated income tax
return filed by EIX, by reason of the filing of an amended return or claim for
refund, or arising out of an audit of such consolidated return by the Internal
Revenue Service or applicable state agency, then the tax Separate Liability of
the Subgroup Members shall be redetermined to give effect to any such adjustment
as if it had been made as part of the filed combined or consolidated return. If
there are carrybacks or carryforwards of net operating losses that reduce the
tax due, they shall be allocated against tax liability among the Subgroup
Members consistent with the principles of Section 1 above. If any interest or
penalty is to be paid or interest received as a result of a tax deficiency or
refund, such interest or penalty shall be allocated in accordance with the
item(s) giving rise to such interest or penalty. If, as a result of such
redetermination, any amounts due from the Subgroup Members, as the case may be,
exceed the amounts previously paid by such party, then payment of such excess
shall be made by the appropriate party, upon demand by EMMH, on the earliest
date on which (i) EIX shall pay, or be deemed to have paid, any additional taxes
resulting from any such adjustment; (ii) EIX shall receive, or be deemed to have
received, a refund of taxes resulting from any such adjustment; or (iii) such
adjustment shall become final. Any payment among the Subgroup Members pursuant
to (i) or (ii) above, however, shall not become final until the adjustment with
respect to which the redetermination was made becomes final. For purposes of
this Section 4, an adjustment shall become final at the time of the expiration
of the applicable statute of limitations with respect to the taxable period to
which such adjustment relates, or, if such adjustment was made pursuant to a
decision of a court, at the time such decision shall become final.
Notwithstanding the foregoing, payment shall only be made to EMMH provided that
such payments are consistent with and are not limited by debt financing
restrictions and covenants.

        5.    Termination.    This Agreement may be terminated or modified by
EMMH in its sole discretion in accordance with its terms. Should the EME and
Subsidiaries Tax Allocation Agreement be terminated or modified, this Agreement
may be terminated or deemed to be similarly modified, as the case may be, as of
the same effective date, in the discretion of EMMH.

        6.    Successors and Beneficiaries.    This Agreement may not be
assigned, pledged, transferred or hypothecated by the Midwest Subgroup or any of
its members, without the express, written consent of EMMH.

        7.    Counterparts.    This Agreement may be executed in one or more
counterparts, each of which shall be an original and all of which taken together
shall constitute one and the same agreement.

        8.    Governing Law.    This Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware.

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        IN WITNESS WHEREOF, the parties have executed this Agreement by their
respective officers thereunto duly authorized as of the date first above
written.

    EDISON MISSION MIDWEST HOLDINGS CO.
 
 
By
/s/  JOHN P. FINNERAN, JR.      

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EDISON MISSION OVERSEAS CO.
 
 
By
/s/  JOHN K. DESHONG      

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MIDWEST GENERATION, LLC
 
 
By
/s/  STEVEN D. EISENBERG      

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Exhibit 10.25

EDISON MISSION MIDWEST HOLDINGS AND SUBSIDIARIES "MIDWEST" TAX ALLOCATION
AGREEMENT