SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549



                                    FORM 8-K


                                 CURRENT REPORT




     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934



                Date of Report (Date of earliest event reported):
                                  July 12, 2002





                               AMEREN CORPORATION
             (Exact name of registrant as specified in its charter)




        Missouri                       1-14756                  43-1723446
(State or other jurisdiction         (Commission             (I.R.S. Employer
     of incorporation)               File Number)            Identification No.)




                 1901 Chouteau Avenue, St. Louis, Missouri 63103
              (Address of principal executive offices and Zip Code)






       Registrant's telephone number, including area code: (314) 621-3222





ITEM 5.   OTHER EVENTS AND REGULATION FD DISCLOSURE

          On July 12, 2002, the Registrant issued a press release stating that
an agreement in principle has been reached in the earnings  complaint case filed
by the Missouri Public Service  Commision  staff against Union Electric  Company
Company d/b/a AmerenUE, the Registrant's  subsidiary,  in July 2001. The details
of the agreement are being  finalized.  The agreement is subject to the approval
of the Missouri  Public  Service  Commission.  The press  release is attached as
Exhibit 99 and is incorporated herein by reference.


ITEM 7.   EXHIBITS

          (c) Exhibits.

              99  Press release, dated July 12, 2002, issued by the Registrant.



                                    SIGNATURE

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

                                       AMEREN CORPORATION
                                        (Registrant)


                                       By   /s/ Martin J. Lyons
                                         -----------------------------------
                                       Name:    Martin J. Lyons
                                       Title:   Controller
                                                (Principal Accounting Officer)


Date:  July 12, 2002





                                  Exhibit Index
                                  -------------

Exhibit No.                        Description
- ----------                         -----------

  99  -     Press release dated July 12, 2002, issued by Ameren Corporation.




                                                                Exhibit 99

[GRAPHIC OMITTED][GRAPHIC OMITTED]
One Ameren Plaza
1901 Chouteau Avenue
St. Louis, MO 63103

Contact:
Analysts:                  Media:                    Investors:
Marty Lyons                Susan Gallagher           Investor Services
(314) 554-2982             (314) 554-2175            Invest@ameren.com

FOR IMMEDIATE RELEASE
- ---------------------

MISSOURI  PUBLIC  SERVICE  COMMISSION   TEMPORARILY  SUSPENDS  PUBLIC  HEARINGS;
AGREEMENT IN PRINCIPLE ON AMERENUE MISSOURI ELECTRIC RATE CASE REACHED

ST. LOUIS,  MO, July 12, 2002--The  regulatory law judge in AmerenUE's  Missouri
electric rate case today  announced the  suspension of public  hearings that the
Missouri Public Service  Commission  (MoPSC) convened July 11 in Jefferson City,
Mo. These hearings were temporarily suspended until 8:30 a.m., Tuesday, July 16.
Upon  announcing  this  suspension,  the  regulatory  law judge  stated that the
parties have reached "an agreement in principle" on the issues in the case.

     Over the next several days,  the parties to the case will be in the process
of preparing a formal written  agreement that will be submitted to the MoPSC. No
details on the agreement will be released until the parties collectively review,
approve,  and file that agreement with the MoPSC.  Any agreement  reached by the
parties must ultimately be approved by the MoPSC.

     AmerenUE is a subsidiary  of St.  Louis-based  Ameren  Corporation.  Ameren
companies serve 1.5 million electric customers and 300,000 natural gas customers
in a  44,500-square-mile  area of Missouri and Illinois.

                             Safe Harbor Statement
Statements made in this release,  which are not based on historical  facts,  are
"forward-looking"  and, accordingly,  involve risks and uncertainties that could
cause actual results to differ  materially from those  discussed.  Although such
"forward-looking"  statements  have  been  made in good  faith  and are based on
reasonable assumptions,  there is no assurance that the expected results will be
achieved.  These statements include (without limitation) statements as to future
expectations,  beliefs, plans, strategies,  objectives,  events, conditions, and
financial  performance.  In connection with the "Safe Harbor"  provisions of the
Private  Securities  Litigation  Reform Act of 1995,  Ameren is  providing  this
cautionary  statement  to identify  important  factors  that could cause  actual
results to differ materially from those anticipated.  The following factors,  in
addition to those  discussed  elsewhere in this  release and in Ameren's  annual
report on SEC Form  10-K for the  fiscal  year  ended  December  31,  2001,  and
subsequent  securities  filings,  could cause results to differ  materially from
management  expectations as suggested by such  "forward-looking"  statements:
o    results  of  settlement  negotiations  with all  pertinent  parties  in the
     pending AmerenUE excess earnings complaint case; and
o    decisions by the Missouri  Public Service  Commission and other  regulatory
     actions.

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