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):
                                February 11, 2003





                               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 9.    REGULATION FD DISCLOSURE

           On February 11, 2003, the Registrant issued a press release
announcing its 2002 earnings. The press release is attached as Exhibit 99 and is
incorporated herein by reference.


ITEM 7.    EXHIBITS

(c) Exhibits.

                99 Press release, dated February 11, 2003, 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:  February 11, 2003



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

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

   99     - Press release dated February 11, 2003, issued by Ameren Corporation.






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                                                                One Ameren Plaza
                                                            1901 Chouteau Avenue
                                                             St. Louis, MO 63103

Contacts:
    Media                     Analysts                    Investors
    Tim Fox                   Bruce Steinke               Investor Services
    (314) 554-3120            (314) 554-2574              (800) 255-2237
    tfox2@ameren.com          bsteinke@ameren.com         invest@ameren.com


                    AMEREN CORPORATION REPORTS 2002 EARNINGS

     St.  Louis,  Mo.,  Feb. 11,  2003---Ameren  Corporation  (NYSE:  AEE) today
announced 2002 net earnings of $382 million, or $2.61 per share ($2.60 diluted),
compared to 2001 earnings of $469 million,  or $3.41 per share ($3.40  diluted).
Excluding  unusual  items,  the company  reported  ongoing 2002 earnings of $440
million,  or $3.01 per share ($3.00 diluted),  compared to 2001 ongoing earnings
of $476 million, or $3.46 per share ($3.45 diluted).  The company's 2002 ongoing
earnings per share was within the guidance for 2002 ongoing earnings of $3.00 to
$3.10 per share provided in December 2002.

     The company  recorded a net loss of $32 million,  or 20 cents per share (20
cents diluted),  for the fourth quarter of 2002, compared to net earnings of $49
million,  or 35 cents per share (34 cents  diluted),  for the fourth  quarter of
2001. Excluding unusual items, fourth quarter 2002 earnings were $26 million, or
18 cents per share (18 cents diluted). There were no unusual items in the fourth
quarter of 2001.

     Net  earnings in 2002  included an after-tax  charge of $58 million,  or 40
cents per share, related to a previously-announced  voluntary retirement program
and  restructuring  charges  associated  with the  retirement  of the  company's
Venice,  Ill., plant and the temporary suspension of operation of two generating
units at the  company's  Meredosia,  Ill.,  plant.  Earnings for 2001 included a
one-time,  after-tax charge of $7 million, or 5 cents per share,  resulting from
the  required  adoption  of a new  accounting  standard  related  to  derivative
financial instruments in January 2001.

     "At Ameren,  we have promised our  stakeholders  performance  leadership by
pursuing a consistent,  long-term  strategy that is focused on our core business
of producing and delivering energy," said Charles W. Mueller, chairman and chief
executive  officer of Ameren  Corporation.  "In 2002, we continued to deliver on
our promises. We entered into a constructive settlement of the largest rate case
in our history,  announced the  acquisition of a high quality utility in CILCORP
Inc., earned superior marks for customer service and environmental  stewardship,
and  significantly  outperformed the Standard & Poor's 500 and Dow Jones Utility
indexes.  We did this while  maintaining a balance sheet and credit ratings that
are among the best in our industry.

                                    - more -

Add One



     "This was accomplished in a year when many companies in our industry failed
to deliver on their promises as the energy sector  grappled with a weak economy,
soft  energy  markets,  highly  leveraged  balance  sheets  and a host of  other
issues," added Mr.  Mueller.  "In fact, a major credit rating agency referred to
2002 as the worst year for our industry since the Great Depression."

     Total  electric  revenues  in 2002 were flat as compared to the prior year.
Warmer summer weather drove higher cooling demand,  but this benefit to revenues
was partially  offset by the impact of the weak economy on industrial  sales and
rate  reductions  associated  with our Missouri  electric rate case  settlement.
During 2002, weather-sensitive  residential and commercial electric kilowatthour
sales rose 7 percent  and 2 percent,  respectively,  while  industrial  electric
sales decreased  approximately 5 percent.  Lower interchange  revenues and sales
compared to the prior year were  attributable  to lower  energy  prices and less
low-cost generation available for sale due primarily to the increased demand for
power from native load customers.

     Other  operations  and  maintenance  expenses  increased $70 million during
2002,  compared to 2001.  This  increase was  primarily  due to higher  employee
medical and pension benefit expenses,  increased plant maintenance expenses, and
higher labor costs due to customary cost of living increases. Earnings were also
reduced in 2002 by increased  depreciation  and financing costs  associated with
capital  additions and the dilutive effect on earnings per share from new common
stock issued during the year to reduce outstanding debt and prefund a portion of
the CILCORP  acquisition.  That  acquisition was completed on Jan. 31, 2003. The
average number of shares outstanding in 2002 was 6 percent greater than in 2001.

     In the fourth  quarter  of 2002,  net  earnings  benefited  from  increased
heating demand relative to 2001, but were reduced by a refueling and maintenance
outage at the company's  Callaway  Nuclear Plant.  Fourth quarter  earnings were
reduced by 13 cents per share due to the Callaway  outage.  Consistent  with the
full year 2002 trends,  net earnings in the fourth  quarter were also lower than
in 2001,  due to the  Missouri  rate  case  settlement  and  increased  employee
benefit, depreciation and financing costs.

     "Looking  to  2003,  we  continue  to  expect  some  of the  challenges  we
experienced  in 2002 to persist,"  said Gary L.  Rainwater,  president and chief
operating  officer  of Ameren  Corporation.  "However,  we have  taken  numerous
prudent actions to significantly lower costs and benefit future operations.  And
we are very excited about the  anticipated  benefits  associated with our recent
acquisition of CILCORP,  which we completed two months earlier than we expected.
This  acquisition  is expected to be accretive to earnings in the first year and
provide meaningful long-term growth opportunities for our company. At Ameren, we
remain  committed to  efficiently  producing  and  delivering  reliable  energy,
maintaining  our  financial   strength  and  flexibility  and  providing  solid,
long-term returns to our shareholders."

                                   -- more --
Add Two



     The company also announced  today that it reaffirmed its  expectation  that
2003  earnings  will be in the range of $2.80 to $3.05 per share.  The company's
2003 earnings range  incorporates the expected  earnings  accretion from CILCORP
and the  issuance of 5.5 million  shares of common stock in January to fund that
acquisition.  This estimate is subject to, among other things, weather, changing
energy market and economic conditions and other risks and uncertainties outlined
in the company's Safe Harbor Statement.

     Ameren will conduct a conference call for financial  analysts at 10:30 a.m.
(Central  Time) on Tuesday,  Feb. 11, to discuss 2002 earnings.  Investors,  the
news media and the public may listen to a live Internet  broadcast of the Ameren
analyst  call at  www.ameren.com  by clicking on "Live  Webcast:  Q4 2002 Ameren
Corporation  Earnings  Conference  Call, Feb. 11, 2003, 11:30 a.m. ET," then the
appropriate audio link.

     The analyst call will also be available  for replay on the Internet for one
week. Telephone playback of the conference call will also be available beginning
at 12:30 p.m. (Central Time), Feb. 11, and until Feb. 18 by dialing,  U.S. (800)
428-6051; international (973) 709-2089, and entering the number: 283709.

     With  assets of more  than  $13.5  billion,  Ameren  owns a diverse  mix of
electric  generating plants  strategically  located in its Midwest market with a
capacity  of more than 14,500  megawatts.  Ameren  serves 1.7  million  electric
customers  and 500,000  natural gas  customers in a  49,000-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, the company 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 past and subsequent
securities  filings,  could cause results to differ  materially  from management
expectations as suggested by such "forward-looking" statements:




     o    the effects of the stipulation and agreement  relating to the AmerenUE
          excess earnings complaint case and other regulatory actions, including
          changes in regulatory policy;
     o    changes in laws and other governmental actions, including monetary and
          fiscal policy;
     o    the  impact on the  company  of  current  regulations  related  to the
          opportunity for customers to choose  alternative  energy  suppliers in
          Illinois;
     o    the effects of increased competition in the future due to, among other
          things,  deregulation of certain aspects of the company's  business at
          both the state and federal levels;
     o    the  effects  of   participation   in  a  Federal  Energy   Regulatory
          Commission-approved  regional  transmission  organization,   including
          activities associated with the Midwest Independent System Operator;
     o    availability  and future market  prices for fuel and purchased  power,
          electricity  and  natural  gas,  including  the use of  financial  and
          derivative instruments and volatility of changes in market prices;
     o    average rates for electricity in the Midwest;
     o    business and economic conditions;
     o    the  impact  of the  adoption  of new  accounting  standards  and  the
          application of appropriate technical accounting rules and guidance;
     o    interest rates and the availability of capital;
     o    actions of ratings agencies and the effects of such actions;
     o    weather conditions;
     o    generation plant construction, installation and performance;
     o    operation of nuclear power facilities and decommissioning costs;
     o    the  effects of  strategic  initiatives,  including  acquisitions  and
          divestitures;
     o    the impact of  current  environmental  regulations  on  utilities  and
          generating   companies  and  the   expectation   that  more  stringent
          requirements  will be introduced  over time,  which could  potentially
          have a negative financial effect;
     o    future wages and employee benefits costs, including changes in returns
          on benefit plan assets;
     o    disruptions  of  the  capital  markets  or  other  events  making  the
          company's access to necessary capital more difficult or costly;
     o    competition from other generating facilities, including new facilities
          that may be developed;
     o    difficulties in integrating CILCO with the company's other businesses;
     o    changes in the coal markets,  environmental  laws or  regulations,  or
          other factors adversely  impacting  synergy  assumptions in connection
          with the CILCORP Inc. acquisition;
     o    cost  and  availability  of  transmission   capacity  for  the  energy
          generated  by the  Company's  generating  facilities  or  required  to
          satisfy energy sales made by the Company; and
     o    legal and administrative proceedings.

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