UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549


                                    FORM 10-Q

[X]  QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934

     For The Quarterly Period Ended June 30, 2003

[ ]  TRANSITION  REPORT  PURSUANT  TO SECTION  13 OR 15(d) OF THE  SECURITIES
     EXCHANGE ACT OF 1934

     For The Transition Period From             to

                          Commission file number 1-3672

                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
             (Exact name of registrant as specified in its charter)


                Illinois                                        37-0211380
     (State or other jurisdiction of                         (I.R.S. Employer
     incorporation or organization)                        Identification No.)



               607 East Adams Street, Springfield, Illinois 62739
              (Address of principal executive offices and Zip Code)

                         Registrant's telephone number,
                       including area code: (217) 523-3600


     Indicate  by check mark  whether the  registrant  (1) has filed all reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrant was required to file such reports),  and (2) has been subject to such
filing requirements for the past 90 days. Yes (X). No ( ).

     Indicate by check mark whether the registrant is an  accelerated  filer (as
defined in Rule 12b-2 of the Securities Exchange Act of 1934). Yes ( ). No (X).

     Shares outstanding of the registrant's  common stock as of August 14, 2003:
Common Stock, no par value,  held by Ameren  Corporation  (parent company of the
registrant) - 25,452,373.


<PAGE>
<TABLE>
<CAPTION>




                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY

                                TABLE OF CONTENTS


                                                                                                                   Page
                                                                                                                   ----
<S>         <C>                                                                                                    <C>
PART I.      Financial Information

   ITEM 1.   Financial Statements (Unaudited)
             Balance Sheet at June 30, 2003 and December 31, 2002..............................................     2
             Statement of Income for the three and six months ended June 30, 2003 and 2002.....................     3
             Statement of Cash Flows for the six months ended June 30, 2003 and 2002...........................     4
             Statement of Common Stockholder's Equity for the three and six months ended June 30, 2003 and 2002     5
             Notes to Financial Statements.....................................................................     6

   ITEM 2.   Management's Discussion and Analysis of Financial Condition and Results of Operations.............    14

   ITEM 3.   Quantitative and Qualitative Disclosures About Market Risk........................................    20

   ITEM 4.   Controls and Procedures...........................................................................    21

             Forward-Looking Statements........................................................................    21

PART II.     Other Information

   ITEM 1.   Legal Proceedings.................................................................................    23

   ITEM 4.   Submission of Matters to a Vote of Security Holders...............................................    24

   ITEM 5.   Other Information.................................................................................    24

   ITEM 6.   Exhibits and Reports on Form 8-K..................................................................    24

SIGNATURE......................................................................................................    26

</TABLE>

     This Form 10-Q contains "forward-looking  statements" within the meaning of
     Section  21E of  the  Securities  Exchange  Act  of  1934.  Forward-looking
     statements  should be read with the  cautionary  statements  and  important
     factors   included   in  this  Form  10-Q  at  Part  I  under  the  heading
     "Forward-Looking Statements." Forward-looking statements are all statements
     other than statements of historical  fact,  including those statements that
     are  identified  by  the  use  of  the  words  "anticipates,"  "estimates,"
     "expects,"   "intends,"  "plans,"   "predicts,"   "projects,"  and  similar
     expressions.


                                       1

<PAGE>
<TABLE>
<CAPTION>

                                PART I. FINANCIAL INFORMATION

ITEM 1.  Financial Statements.

                            CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                                         BALANCE SHEET
                                   (Unaudited, in millions)

                                                                                June 30,   December 31,
                                                                                  2003        2002
                                                                                --------   ------------
<S>                                                                            <C>        <C>

ASSETS:
Property and plant, net                                                         $   822    $   825
Investments and other assets:
   Intercompany notes receivable - Generating Company                               324        373
   Intercompany tax receivable - Generating Company                                 156        162
   Other assets                                                                      18         17
                                                                                --------   --------
         Total investments and other assets                                         498        552
                                                                                --------   --------
Current assets:
   Cash and cash equivalents                                                         18         17
   Accounts receivable - trade (less allowance for doubtful
      accounts of $1 and $1, respectively)                                           45         53
   Unbilled revenue                                                                  65         74
   Intercompany notes receivable                                                      -         16
   Miscellaneous accounts and notes receivable                                       18         22
   Current portion of intercompany notes receivable - Generating Company             49         46
   Current portion of intercompany tax receivable - Generating Company               13         13
   Materials and supplies, at average cost                                           33         41
   Other current assets                                                               6          7
                                                                                --------   --------
      Total current assets                                                          247        289
                                                                                --------   --------
Regulatory assets                                                                    29         31
                                                                                --------   --------
Total Assets                                                                    $ 1,596    $ 1,697
                                                                                ========   ========

CAPITAL AND LIABILITIES:
Capitalization:
   Common stock, no par value, 45.0 shares authorized -
     25.5 shares outstanding                                                    $   120    $   120
   Retained earnings                                                                370        405
   Accumulated other comprehensive income (loss)                                    (15)       (13)
                                                                                --------   --------
      Total common stockholder's equity                                             475        512
                                                                                --------   --------
   Preferred stock not subject to mandatory redemption                               80         80
   Long-term debt, net                                                              485        534
                                                                                --------   --------
      Total capitalization                                                        1,040      1,126
                                                                                --------   --------
Current liabilities:
   Current maturities of long-term debt                                               -         45
   Accounts and wages payable                                                        86         87
   Intercompany notes payable                                                        39          -
   Taxes accrued                                                                     32         32
   Other current liabilities                                                         25         26
                                                                                --------   --------
      Total current liabilities                                                     182        190
                                                                                --------   --------
Accumulated deferred income taxes                                                   271        282
Accumulated deferred investment tax credits                                          12         13
Regulatory liabilities                                                               15         15
Other deferred credits and liabilities                                               76         71
                                                                                --------   --------
Total Capital and Liabilities                                                   $ 1,596    $ 1,697
                                                                                ========   ========

See Notes to Financial Statements.

</TABLE>


                                       2


<PAGE>
<TABLE>
<CAPTION>

                    CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                               STATEMENT OF INCOME
                            (Unaudited, in millions)


                                               Three Months Ended  Six Months Ended
                                                    June 30,            June 30,
                                                ------------------ ----------------
                                                 2003     2002    2003     2002
                                                -----    -----   -----    ------
<S>                                            <C>      <C>     <C>      <C>
OPERATING REVENUES:
   Electric                                     $ 137    $ 161   $ 269    $ 311
   Gas                                             30       26     107       91
                                                ------   ------  ------   ------
     Total operating revenues                     167      187     376      402
                                                ------   ------  ------   ------
OPERATING EXPENSES:
   Purchased power                                 82      101     168      206
   Gas                                             18       12      71       56
   Other operations and maintenance                38       40      80       81
   Depreciation and amortization                   13       13      26       25
   Income taxes                                     -        4      (1)       5
   Other taxes                                      7        6      16       15
                                                ------   ------  ------   ------
     Total operating expenses                     158      176     360      388
                                                ------   ------  ------   ------

OPERATING INCOME                                    9       11      16       14

OTHER INCOME AND (DEDUCTIONS):
   Miscellaneous, net -
     Miscellaneous income                           7        7      14       17
     Miscellaneous expense                         (1)       -      (2)      (1)
     Income taxes                                  (3)       -      (5)       -
                                                ------   ------  ------   ------
     Total other income and (deductions)            3        7       7       16
                                                ------   ------  ------   ------

INTEREST CHARGES                                    9       10      18       20
                                                ------   ------  ------   ------

NET INCOME                                          3        8       5       10

PREFERRED STOCK DIVIDENDS                           -        1       1        2
                                                ------   ------  ------   ------
NET INCOME AFTER PREFERRED STOCK DIVIDENDS      $   3    $   7   $   4    $   8
                                                ======   ======  ======   ======

See Notes to Financial Statements.


</TABLE>


                                       3
<PAGE>
<TABLE>
<CAPTION>

                   CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                           STATEMENT OF CASH FLOWS
                           (Unaudited, in millions)

                                                                    Six Months Ended
                                                                         June 30,
                                                                    ----------------
                                                                      2003     2002
                                                                    ------    ------
<S>                                                                 <C>     <C>
Cash Flows From Operating:
   Net income                                                        $  5     $ 10
   Adjustments to reconcile net income to net cash
       provided by operating activities:
         Depreciation and amortization                                 26       25
         Amortization of debt issuance costs and premium/discounts      -        1
         Deferred income taxes, net                                   (11)      (9)
         Deferred investment tax credits, net                          (1)      (1)
         Other                                                         (2)       -
         Changes in assets and liabilities:
               Receivables, net                                        21      (14)
               Materials and supplies                                   8        9
               Accounts and wages payable                              (1)     (29)
               Taxes accrued                                            -        6
               Assets, other                                            7       15
               Liabilities, other                                       5        2
                                                                     -----    -----
Net cash provided by operating activities                              57       15
                                                                     -----    -----

Cash Flows From Investing:
   Construction expenditures                                          (22)     (26)
   Intercompany notes receivable                                       62       43
                                                                     -----    -----
Net cash provided by investing activities                              40       17
                                                                     -----    -----

Cash Flows From Financing:
   Dividends on common stock                                          (39)     (31)
   Dividends on preferred stock                                        (1)      (2)
   Redemptions:
      Long-term debt                                                  (95)      (5)
   Issuances:
      Intercompany notes payable                                       39        -
                                                                     -----    -----
Net cash used in financing activities                                 (96)     (38)
                                                                     -----    -----

Net change in cash and cash equivalents                                 1       (6)
Cash and cash equivalents at beginning of year                         17       26
                                                                     -----    -----
Cash and cash equivalents at end of period                           $ 18     $ 20
                                                                     =====    =====

Cash paid during the periods:
   Interest                                                          $ 20     $ 20
   Income taxes, net                                                   14        9

See Notes to Financial Statements.

</TABLE>

                                       4

<PAGE>
<TABLE>
<CAPTION>


                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                    STATEMENT OF COMMON STOCKHOLDER'S EQUITY
                            (Unaudited, in millions)

                                                                   Three Months Ended    Six Months Ended
                                                                      June 30,              June 30,
                                                                   ------------------  -------------------
                                                                      2003     2002     2003     2002
                                                                     ------   ------   -----    -----
<S>                                                                 <C>      <C>      <C>      <C>
Common stock                                                         $ 120    $ 120    $ 120    $ 120

Retained earnings
   Beginning balance                                                   387      430      405      444
   Net income                                                            3        8        5       10
   Common stock dividends                                              (20)     (16)     (39)     (31)
   Preferred stock dividends                                             -       (1)      (1)      (2)
                                                                      -----   ------   ------   ------
                                                                       370      421      370      421
                                                                      -----   ------   ------   ------

Accumulated other comprehensive income (loss)
   Beginning balance - derivative financial instruments                  -        -        -        -
   Change in derivative financial instruments in current period         (2)       -       (2)       -
                                                                     ------   ------   ------   ------
                                                                        (2)       -       (2)       -
                                                                     ------   ------   ------   ------
   Beginning balance - minimum pension liability                       (13)       -      (13)       -
   Change in minimum pension liability in current period                 -        -        -        -
                                                                     ------   ------   ------   ------
                                                                       (13)       -      (13)        -
                                                                     ------   ------   ------   ------

                                                                       (15)       -      (15)       -
                                                                     ------   ------   ------   ------

Total common stockholder's equity                                    $ 475    $ 541    $ 475    $ 541
                                                                     ======   ======   ======   ======


Comprehensive income, net of taxes
   Net income                                                        $   3    $   8    $   5    $  10
   Unrealized net gain/(loss) on derivative hedging instruments,
        net of income taxes of $(1), $-, $(1) and $-, respectively      (2)       -       (2)       -
                                                                     ------   ------   ------   ------
Total comprehensive income, net of taxes                             $   1    $   8    $   3    $  10
                                                                     ======   ======   ======   ======

See Notes to Financial Statements.
</TABLE>

                                       5

<PAGE>
CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
June 30, 2003


NOTE 1 - Summary of Significant Accounting Policies

General

     Central  Illinois  Public Service  Company,  headquartered  in Springfield,
Illinois,  operates as  AmerenCIPS  and is a  wholly-owned  subsidiary of Ameren
Corporation (Ameren). Our principal business is the rate-regulated  transmission
and  distribution  of  electricity  and  the  distribution  of  natural  gas  to
residential, commercial, industrial and wholesale users in Illinois. Ameren is a
public  utility  holding  company  registered  with the  Securities and Exchange
Commission  (SEC) under the Public Utility  Holding  Company Act of 1935 (PUHCA)
and is headquartered in St. Louis, Missouri.  Ameren's principal business is the
generation, transmission and distribution of electricity and the distribution of
natural gas to  residential,  commercial,  industrial and wholesale users in the
central United States.  In addition to us, Ameren's  principal  subsidiaries and
our affiliates are as follows:
o    Union  Electric   Company,   which  operates  a   rate-regulated   electric
     generation,  transmission and distribution  business,  and a rate-regulated
     natural gas distribution business in Missouri and Illinois as AmerenUE.
o    Central  Illinois  Light Company,  a subsidiary of CILCORP Inc.  (CILCORP),
     which operates a  rate-regulated  electric  transmission  and  distribution
     business, an electric generation business and a rate-regulated  natural gas
     distribution  business in Illinois as  AmerenCILCO.  Ameren  completed  its
     acquisition of CILCORP on January 31, 2003.
o    AmerenEnergy  Resources Company (Resources Company),  which consists of non
     rate-regulated  operations.  Subsidiaries include  AmerenEnergy  Generating
     Company  (Generating  Company),  which operates Ameren's non rate-regulated
     electric  generation  in  Missouri  and  Illinois,  AmerenEnergy  Marketing
     Company (Marketing Company), which markets power for periods primarily over
     one year,  AmerenEnergy Fuels and Services Company, which procures fuel and
     manages the related risks for Ameren-affiliated companies, and AmerenEnergy
     Medina  Valley Cogen (No.  4), LLC,  which  indirectly  owns a 40 megawatt,
     gas-fired electric  generation plant. On February 4, 2003, Ameren completed
     its acquisition of AES Medina Valley Cogen (No. 4), LLC (Medina Valley) and
     renamed it  AmerenEnergy  Medina  Valley  Cogen (No.  4),  LLC.  Generating
     Company  supplies  electric  power to  Marketing  Company  which,  in turn,
     supplies  us with  power  under  a power  supply  agreement  (Power  Supply
     Agreement).
o    AmerenEnergy,  Inc.  (AmerenEnergy),  which serves as a power marketing and
     risk management agent for  Ameren-affiliated  companies for transactions of
     primarily less than one year.
o    Electric  Energy,  Inc.  (EEI),  which  operates  electric  generation  and
     transmission facilities in Illinois. Ameren has a 60% ownership interest in
     EEI.
o    Ameren Services  Company (Ameren  Services),  which provides shared support
     services to Ameren and its  subsidiaries,  including us.  Charges are based
     upon the actual  costs  incurred  by Ameren  Services,  as  required by the
     PUHCA.

     When we refer to  AmerenCIPS,  our, we or us, we are  referring  to Central
Illinois  Public  Service  Company.  All tabular dollar amounts are in millions,
unless otherwise indicated.

     Our accounting policies conform to generally accepted accounting principles
in the United States (GAAP).  Our financial  statements  reflect all adjustments
(which include normal,  recurring adjustments)  necessary, in our opinion, for a
fair  presentation of our interim results.  These  statements  should be read in
conjunction with the financial statements and notes thereto included in our 2002
Annual Report on Form 10-K.

                                       6
<PAGE>


     The  preparation of financial  statements in conformity  with GAAP requires
management  to make  certain  estimates  and  assumptions.  Such  estimates  and
assumptions  affect reported amounts of assets and liabilities and disclosure of
contingent  assets and  liabilities at the date of the financial  statements and
the reported amounts of revenues and expenses during the reported period. Actual
results could differ from those estimates.  Certain  reclassifications have been
made to prior years' financial statements to conform to 2003 reporting.

Accounting Changes and Other Matters

Statement of Financial  Accounting  Standards  (SFAS) No. 143 - "Accounting  for
Asset Retirement Obligations"

     We adopted the provisions of SFAS 143 effective  January 1, 2003.  SFAS 143
provides the accounting requirements for asset retirement obligations associated
with tangible,  long-lived assets.  SFAS 143 requires us to record the estimated
fair value of legal  obligations  associated  with the  retirement  of  tangible
long-lived  assets in the period in which the  liabilities  are  incurred and to
capitalize  a  corresponding  amount  as part of the book  value of the  related
long-lived  asset.  In  subsequent  periods,  we are  required  to adjust  asset
retirement  obligations based on changes in estimated fair value.  Corresponding
increases in asset book values are depreciated over the remaining useful life of
the related asset. Uncertainties as to the probability, timing or amount of cash
flows  associated with an asset  retirement  obligation  affect our estimates of
fair value.

     We have determined that certain other asset retirement  obligations  exist.
However,  we are unable to estimate the fair value of those obligations  because
the probability,  timing or amount of cash flows associated with the obligations
are  indeterminable.  We do not believe that these  obligations,  when incurred,
will have a  material  adverse  impact on our  financial  position,  results  of
operations or liquidity.

     Historically,  our depreciation  methodology has included an estimated cost
of dismantling  and removing plant from service upon  retirement.  Because these
estimated  costs of removal have been included in the cost of service upon which
our present utility rates are based, and with the expectation that this practice
will continue in the jurisdictions in which we operate, adoption of SFAS 143 did
not  result  in any  change  in the  depreciation  accounting  practices  of our
rate-regulated  operations.  We have estimated  future removal costs embedded in
accumulated   depreciation   related  to   rate-regulated   plant   assets  were
approximately $127 million at June 30, 2003.

SFAS  No.  150  -   "Accounting   for   Certain   Financial   Instruments   with
Characteristics of Both Liabilities and Equity"

     In May 2003, the FASB issued SFAS 150 that established standards for how an
issuer   classifies   and   measures   certain   financial    instruments   with
characteristics  of both  liabilities  and equity.  SFAS 150 requires  financial
instruments  that  were  issued  in the  form of  shares  with an  unconditional
obligation,  where the issuer must redeem the  instrument  by  transferring  its
assets on a specified date, be classified as liabilities.  Accordingly, SFAS 150
requires issuers to classify  mandatorily  redeemable  financial  instruments as
liabilities. SFAS 150 also requires such financial instruments to be measured at
fair value and a cumulative  effect adjustment to be recognized in the statement
of income for any difference  between the carrying  amount and fair value.  SFAS
150 will be effective in the third  quarter of 2003.  SFAS 150 will not have any
impact on our  financial  position,  results of  operations  or  liquidity  upon
adoption in the third quarter of 2003.


                                       7

<PAGE>

FASB Interpretation No. (FIN) 46 - "Consolidation of Variable Interest Entities,
an  Interpretation of Accounting  Research  Bulletin (ARB) No. 51,  Consolidated
Financial Statements"

     The FASB issued FIN 46 in January  2003.  FIN 46  provides  guidance on the
identification  of, and financial  reporting for, entities over which control is
achieved  through  means other than voting  rights;  such  entities are known as
variable-interest entities (VIEs). FIN 46 will determine the following:

     o    Whether  consolidation  is required under the  "controlling  financial
          interest" model of ARB 51, or other existing authoritative guidance;
     o    Or, alternatively,  whether the  variable-interest  model under FIN 46
          should be used to account for existing and new entities.

     The  initial  application  of FIN 46  depends  on the date that the VIE was
created. For public entities, FIN 46 is effective no later than the beginning of
the first  interim  period that starts after June 15, 2003. At this time, we are
assessing the impact of FIN 46 on our financial position,  results of operations
or liquidity upon adoption in the third quarter of 2003.

Interchange Revenues

     Interchange  revenues  included in Operating  Revenues - Electric  were $10
million for the three  months  ended June 30,  2003 (2002 - $8 million)  and $18
million for the six months ended June 30, 2003 (2002 - $18 million).

Purchased Power

     Purchased  power included in Operating  Expenses - Purchased  Power was $82
million for the three months ended June 30, 2003 (2002 - $101  million) and $168
million for the six months ended June 30, 2003 (2002 - $206 million).

Excise Taxes

     Excise taxes on our  Illinois gas customer  bills are imposed on us and are
recorded gross in Operating  Revenues and Other Taxes.  Excise taxes recorded in
Operating Revenues and Other Taxes for the three months ended June 30, 2003 were
$3 million  (2002 - $2 million) and $8 million for the six months ended June 30,
2003 (2002 - $7 million).  Excise taxes applicable to Illinois electric customer
bills are imposed on the consumer and are  recorded as tax  collections  payable
and included in Taxes Accrued on the Balance Sheet.

Pension

     At December 31, 2002,  Ameren recorded a minimum pension  liability of $102
million,   after  taxes,  which  resulted  in  a  charge  to  Accumulated  Other
Comprehensive  Income  (Loss)(OCI) and a reduction in stockholders'  equity. Our
portion of the minimum pension liability was $13 million,  after taxes. Based on
changes in interest rates,  Ameren may need to change its actuarial  assumptions
for its pension plan at December 31, 2003,  which could result in a  requirement
to record an additional minimum pension liability.


NOTE 2 - Rate and Regulatory Matters

Intercompany Purchase of Illinois Service Territory

     On May 30, 2003, in a proceeding  before the Illinois  Commerce  Commission
(ICC)  involving a request for approval of an  intercompany  transfer of certain
electric  generating  facilities from Generating  Company to AmerenUE,  AmerenUE
filed a Notice of Withdrawal  with the ICC stating that AmerenUE had elected not
to pursue  approval of the transfer  and was  withdrawing  its  request.  In the
Notice,  AmerenUE stated that the concerns  expressed by the ICC Staff regarding
AmerenUE's  means of satisfying its generating  capacity  needs,  as well as the
Missouri Public Service  Commission's  (MoPSC) views of the

                                       8

<PAGE>

appropriate means of meeting generating capacity obligations,  have demonstrated
to AmerenUE the difficulty of a single company  operating as an electric utility
in both a regulated generation  jurisdiction such as Missouri and an unregulated
generation  jurisdiction such as Illinois.  To remedy this difficulty,  AmerenUE
announced in the Notice its plan to limit its public  utility  operations to the
State of Missouri and to discontinue  operating as a public  utility  subject to
ICC  regulation.  AmerenUE  intends  to  accomplish  this  plan by  selling  its
Illinois-based electric and natural gas businesses, including its Illinois-based
distribution  assets and  certain of its  transmission  assets,  to us. In 2002,
AmerenUE's  Illinois service territory generated revenues of $166 million and is
estimated  to have a net book  value  of $138  million  at  December  31,  2003.
AmerenUE's   electric   generating   facilities  and  certain  of  its  electric
transmission  facilities in Illinois  would not be part of the sale. The sale of
AmerenUE's  Illinois-based utility businesses to us will require the approval of
the ICC, the Federal Energy Regulatory  Commission (FERC), the MoPSC and the SEC
under the  provisions  of the PUHCA.  On June 13,  2003,  the ICC Staff  filed a
response to AmerenUE's  Notice of Withdrawal  indicating  that the ICC Staff did
not object to it and on July 23,  2003,  the ICC issued an order  accepting  the
withdrawal.  In the third  quarter  of 2003,  AmerenUE  expects to file with the
MoPSC,  the  ICC,  the  FERC  and  the SEC for the  authority  to  transfer  its
Illinois-based  utility businesses,  at net book value, to us. AmerenUE proposes
to transfer approximately one-half of the assets directly to us in consideration
for a promissory  note, and  approximately  one-half of the assets by means of a
dividend in kind to Ameren followed by a capital contribution of the assets from
Ameren to us.


     We  are  unable  to  predict   the ultimate  outcome  of  these  regulatory
proceedings or the timing of the final decisions of the various  agencies.  As a
result,  we are not able at this time to estimate the impact of this transaction
on our financial position, results of operations or liquidity.

Regional Transmission Organization (RTO)

     Since April 2002, we, AmerenUE and subsidiaries of FirstEnergy  Corporation
and NiSource Inc.  (collectively the GridAmerica Companies) have participated in
a number  of  filings  at the FERC in an effort  to form  GridAmerica  LLC as an
independent transmission company (ITC). On December 19, 2002, the FERC issued an
order  conditionally  approving the formation and operation of GridAmerica as an
ITC within the Midwest  Independent  System Operator  (Midwest ISO),  subject to
further compliance filings.

     In response to the December 19, 2002 order, the GridAmerica  Companies made
three  additional  filings at the FERC.  On January 31,  2003,  the  GridAmerica
Companies filed a request for  authorization to transfer  functional  control of
certain   transmission  assets  to  GridAmerica.   On  February  18,  2003,  the
GridAmerica  Companies  filed  revised  agreements  codifying  the formation and
operation  of  GridAmerica  to  reflect  changes  requested  by the  FERC in the
December  19, 2002 order.  On  February  28,  2003,  the  GridAmerica  Companies
together  with the  Midwest ISO filed  revisions  to the Midwest ISO Open Access
Transmission  Tariff (OATT) to provide  rates for service over the  transmission
facilities to be transferred to GridAmerica by the GridAmerica Companies.

     On April 30,  2003,  the FERC issued  orders in response to the January 31,
2003 and February  28, 2003  filings.  In its order  regarding  the  GridAmerica
Companies' request to transfer  functional control of their transmission  assets
to GridAmerica,  the FERC  authorized the transfer.  In response to the February
28,  2003  filing,  the FERC  accepted  the  amendments  to the Midwest ISO OATT
effective upon the  commencement  of service over the  GridAmerica  transmission
facilities  under the  Midwest  ISO OATT,  suspended  the  proposed  rates for a
nominal  period,  subject to refund,  and  established  hearing  and  settlement
procedures  to determine  the justness and  reasonableness  of the proposed rate
amendments  to the Midwest  ISO OATT.  At this time,  the  parties are  pursuing
settlement of the disputed rate issues.  Absent  settlement,  the rates filed in
the February 28, 2003 filing will go into effect on October 1, 2003,  subject to
refund.  On May 15, 2003,  the FERC issued an order  accepting  the February 18,
2003 compliance filing.

     Once  GridAmerica  becomes  operational and Ameren has secured  approval to
participate  in GridAmerica  from the MoPSC,  the FERC has ordered the return of
the $18 million exit fee, with interest,  paid by Ameren when it previously left
the Midwest ISO. Our portion of the exit fee to be returned is $5 million. Until
the tariffs and other  material  terms of our and  AmerenUE's  participation  in
GridAmerica,  and GridAmerica's  participation in the Midwest ISO, are finalized
and  approved by the FERC,  we are unable to predict  the impact  that  on-going
regional  transmission  organization  developments  will  have on our  financial
position,  results of operations or liquidity.  We expect  GridAmerica to become
operational in late 2003, subject to regulatory approvals.


                                       9
<PAGE>

     In July 2003, the FERC issued an Order (July Order) that could  potentially
reduce Ameren's,  as well as other  utilities',  "through and out"  transmission
revenues  effective  November 1, 2003,  reversing an Administrative  Law Judge's
previous  decision on this matter.  The revenues  subject to  elimination by the
July Order are those revenues from transmission reservations that travel through
or out of our  transmission  system and are also used to provide  electricity to
load within the Midwest ISO or PJM Interconnection LLC systems. The magnitude of
the potential net revenue reduction resulting from the July Order is still being
evaluated,  but could be up to $20 to $25 million annually for Ameren.  While it
is anticipated that Ameren's  transmission revenues could be reduced by the July
Order,  transmission  expenses  for our  affiliates  could also be reduced.  Our
portion of the potential net revenue  reduction  could be up to $6 to $8 million
annually.  Moreover, the FERC's Order explicitly permits companies participating
in an RTO to seek  collection  of the lost  "through and out"  revenues  through
other rate  mechanisms.  At this time,  we intend to seek  rehearing of the July
Order.  We also intend to seek recovery of any potential  lost "through and out"
revenues through rate mechanisms acknowledged by the FERC in the July Order.

Standard Market Design Notice of Proposed Rulemaking (NOPR)

     On July 31, 2002,  the FERC issued a Standard  Market Design NOPR. The NOPR
proposes  a number of  changes  to the way the  current  wholesale  transmission
service and energy  markets are operated.  Specifically,  the NOPR calls for all
jurisdictional  transmission  facilities  to be placed  under the  control of an
independent   transmission   provider  (similar  to  an  RTO),  proposes  a  new
transmission  service tariff that provides a single form of transmission service
for all users of the  transmission  system  including  bundled  retail load, and
proposes  a new  energy  market  and  congestion  management  system  that  uses
locational marginal pricing as its basis.

     Although  issuance of the final rule is  uncertain  and its  implementation
schedule is unknown, the Midwest ISO is already in the process of implementing a
separate  market  design  similar to the proposed  market design in the NOPR. In
July 2003,  the Midwest  ISO filed with the FERC a revised  OATT  codifying  the
terms and conditions  under which it will  implement the new market design.  The
Midwest ISO has targeted March 2004 as the start date for implementation. We are
reviewing the Midwest ISO's market design and the potential impact of the market
design on the cost and reliability of service to retail customers. At this time,
we are unable to predict the ultimate  impact the new market design will have on
our future financial position, results of operations or liquidity.

Illinois Gas

     In November 2002, we filed a request with the ICC to increase  annual rates
for  natural  gas  service  by  approximately  $16  million.  The ICC Staff has
recommended an annual increase of approximately $8 million.  In addition,  other
parties have proposed a lower increase in this case.  Hearings were completed in
June and July 2003.  The ICC has until October 2003 to render a decision in this
gas case and any rate change is expected to be effective in November 2003.

Illinois Electric

     Commencing  in  2002,  all  of our  Illinois  residential,  commercial  and
industrial  customers  had  choice in  electric  suppliers  as  provided  by the
Electric Service Customer Choice and Rate Relief Law of 1997. Several commercial
and industrial  customers  switched to Marketing Company for their energy supply
resulting in a decline in our revenues and a corresponding decrease in purchased
power of approximately  $23 million for the three months ended June 30, 2003 and
$42  million six months  ended June 30,  2003.  We continue to provide  electric
delivery  service to these  customers  and  charge  them ICC  approved  delivery
service tariff rates for that service.

                                       10
<PAGE>


NOTE 3 - Related Party Transactions

     We have  transactions  in the normal course of business with Ameren and its
other  subsidiaries.   These  transactions  are  primarily  comprised  of  power
purchases and sales, as well as other services received or rendered. An electric
power  supply  agreement  was entered into  between  Generating  Company and its
non-regulated  affiliate,  Marketing Company  (Generating-Marketing  Agreement),
both wholly-owned  subsidiaries of Resources  Company.  Subsequently,  Marketing
Company  entered into the Power Supply  Agreement  with our company to supply us
sufficient  energy and capacity to meet our  obligations to offer service to our
retail customers and to fulfill our other obligations  under applicable  federal
and state  tariffs or contracts  through  December  31,  2004.  The Power Supply
Agreement and the Generating-Marketing Agreement may be terminated upon at least
one year's notice given by either party, but in no event can either agreement be
terminated  prior to December 31, 2004. We expect  Marketing  Company to seek to
extend the Power Supply Agreement through December 31, 2006. An extension of the
Power Supply Agreement will depend on compliance with regulatory requirements in
effect as to  Marketing  Company  at the time;  and we  cannot  predict  whether
Marketing Company will be successful in securing an extension of this agreement.
The ICC  authorized  the  extension  of this  agreement  in its order  approving
Ameren's  acquisition of CILCORP.  A portion of the capacity and energy supplied
by  Generating  Company to Marketing  Company will be resold to us for resale to
our native load customers at rates  specified by the ICC, which  approximate the
historical  regulatory  rates for  generation,  or to retail  customers  allowed
choice of an electric  supplier under state law at market-based  prices.  We are
obligated  to pay a capacity  charge per  megawatt  hour,  per year to Marketing
Company or the greater of our forecasted peak demand or actual demand plus sales
at market based rates.  We are also subject to energy  charges per megawatt hour
for all energy sales other than sales at  market-based  rates.  Charges are paid
monthly. Due to the Generating-Marketing Agreement, Generating Company bears the
all generation related operating risks, including plant performance, operations,
maintenance,  efficiency,  employee  retention and other  matters.  There are no
guarantees,  bargain  purchase  options or other terms that may convey to us the
right  to  use  the  property,   plant  and  equipment  of  Generating  Company.
Intercompany  power purchases under the Power Supply  Agreement and from EEI, an
affiliate,  totaled $82 million for the three months ended June 30, 2003 (2002 -
$101  million)  and $168  million for the six months ended June 30, 2003 (2002 -
$206 million).

     We have the ability to borrow from Ameren and  AmerenUE,  through a utility
money pool  agreement.  Ameren  Services  administers the utility money pool and
tracks internal and external funds separately.  Internal funds are surplus funds
contributed to the money pool from participants.  The primary source of external
funds for the  utility  money pool at June 30,  2003 was  AmerenUE's  commercial
paper program.  Through the utility money pool, we can access  committed  credit
facilities at Ameren and AmerenUE,  which totaled $757 million at June 30, 2003.
These  facilities  are in addition to our own $15  million in  committed  credit
facilities.  The total amount available to us at any given time from the utility
money  pool is  reduced  by the  amount of  borrowings  by our  affiliates,  but
increased to the extent  Ameren,  AmerenUE or Ameren  Services has surplus funds
and the availability of other external  borrowing  sources.  The availability of
funds is also determined by funding  requirements and limits  established by the
PUHCA.  We, along with AmerenUE and Ameren  Services,  rely on the utility money
pool to coordinate and provide for certain  short-term  cash and working capital
requirements.  Borrowers receiving a loan under the utility money pool agreement
must repay the principal  amount of such loan,  together with accrued  interest.
Interest is calculated at varying rates of interest depending on the composition
of internal and external funds in the utility money pool.  The average  interest
rate for the  utility  money pool for the three  months  ended June 30, 2003 was
1.19%  (2002 - 1.75%) and 1.25% for the six months  ended June 30,  2003 (2002 -
1.77%).  At  June  30,  2003,  we did  not  have  any  intercompany  receivables
outstanding (December 31, 2002 - $16 million) through the utility money pool. We
had $39 million in intercompany  money pool  borrowings  outstanding at June 30,
2003 (December 31, 2002 - none).  Subject to the receipt of regulatory approval,
which is being pursued,  AmerenCILCO  will also participate in the utility money
pool arrangement.

     Costs of support  services  provided by Ameren  Services,  including wages,
employee benefits and professional services, are based on actual costs incurred.
Support services  provided by Ameren Services  included in Operating  Expenses -
Other  Operations  and  Maintenance  for the three  months  ended June 30,  2003
totaled  $14  million  (2002 - $15  million)  and $29 million for the six months
ended June 30, 2003 (2002 - $31 million).

                                       11
<PAGE>



     As of June 30, 2003,  intercompany  receivables  included in  Miscellaneous
Accounts and Notes Receivable were  approximately $12 million (December 31, 2002
- $12 million). As of June 30, 2003,  intercompany payables included in Accounts
and Wages Payables totaled approximately $56 million (2002 - $63 million).

     Our intercompany note receivable from Generating  Company was approximately
$373 million (December 31, 2002 - $419 million) including the current portion of
$49  million  (December  31,  2002 - $46  million)  as of  June  30,  2003.  Our
intercompany  interest income recorded in Miscellaneous Income was approximately
$7 million for the three  months ended June 30, 2003 (2002 - $7 million) and $14
million for the six months ended June 30, 2003 (2002 - $16 million).


NOTE 4 - Property and Plant, Net
<TABLE>
<CAPTION>

Property and plant, net at June 30, 2003 and December 31, 2002, consisted of the
following:

---------------------------------------------------------------------------------------
                                                      June 30, 2003   December 31, 2002
---------------------------------------------------------------------------------------
<S>                                                      <C>           <C>
Property and plant, at original cost:
 Electric                                                 $1,267          $1,248
 Gas                                                         292             290
 Other                                                         5               5
---------------------------------------------------------------------------------------
                                                          $1,564          $1,543
  Less accumulated depreciation and amortization             752             732
---------------------------------------------------------------------------------------
                                                             812             811
Construction work in progress:
 Other                                                        10              14
---------------------------------------------------------------------------------------
Property and plant, net                                   $  822          $  825
---------------------------------------------------------------------------------------

</TABLE>

NOTE 5 - Debt Financings

     On April 1, 2003, we repaid $40 million first  mortgage bonds 6.375% Series
Z which matured on that date. We also redeemed in April 2003,  prior to maturity
and at par, our $50 million first mortgage bonds 7.5% Series X due July 1, 2007.

     In July  2003,  Ameren  entered  into two new  credit  agreements  for $470
million  in  revolving  credit  facilities  to be  used  for  general  corporate
purposes,  including the support of commercial paper programs.  The $470 million
in new facilities  includes a $235 million 364-day revolving credit facility and
a $235 million three-year revolving credit facility. These new credit facilities
replaced Ameren's existing $270 million 364-day revolving credit facility, which
matured in July 2003, and a $200 million  facility,  which would have matured in
December 2003. The new credit facilities contain provisions which require Ameren
to  meet  minimum  Employee  Retirement  Income  Security  Act  (ERISA)  funding
requirements  for Ameren's  pension plan. The prior credit  facilities  included
more  restrictive  provisions  related to the funded status of Ameren's  pension
plan,  which are not present in the new facilities.  In addition,  in July 2003,
Ameren  Corporation  entered  into an  amendment  of an  existing  $130  million
multi-year credit facility that similarly modified the ERISA-related  provisions
in this facility.  As a result,  all of Ameren's  facilities  require it to meet
minimum ERISA funding  requirements,  but do not otherwise limit the underfunded
status of its pension plan.  At July 31, 2003,  all of such  borrowing  capacity
under these facilities was available.

     At June 30, 2003,  neither Ameren,  nor any of its subsidiaries,  including
us, had any  off-balance  sheet  financing  arrangements,  other than  operating
leases entered into in the ordinary course of business.

     Amortization  of debt issuance costs and any premium or discounts were less
than $1 million for the three months ended June 30, 2003 (2002 - $1 million) and
less than $1 million for the six months  ended June 30, 2003 (2002 - $1 million)
and were included in interest expense in the income statement.

                                       12

<PAGE>

     At June 30,  2003,  Ameren  and its  subsidiaries,  including  us,  were in
compliance with their financial agreement provisions and covenants.


NOTE 6 - Miscellaneous, Net
<TABLE>
<CAPTION>

     Miscellaneous,  net for the three and six months  ended  June 30,  2003 and
2002 consisted of the following:

---------------------------------------------------------------------------------------
                                                    Three Months          Six Months
                                                2003        2002       2003       2002
---------------------------------------------------------------------------------------
<S><C>                                          <C>         <C>        <C>        <C>
Miscellaneous income:
   Interest and dividend income                  $7          $7         $14        $16
   Other                                          -           -           -          1
---------------------------------------------------------------------------------------
Total miscellaneous income                       $7          $7         $14        $17
---------------------------------------------------------------------------------------
Miscellaneous expense:
  Other                                         $(1)         $-         $(2)       $(1)
---------------------------------------------------------------------------------------
Total miscellaneous expense                     $(1)         $-         $(2)       $(1)
---------------------------------------------------------------------------------------
</TABLE>


NOTE 7 - Segment Information

     Our  business  segments  provide  electric  and gas  service in portions of
Illinois.  The  accounting  policies  of the  segments  are the  same  as  those
described in Note 1 - Summary of Significant  Accounting Policies.  Segment data
includes a charge allocating costs of administrative support services to each of
the  segments.  These costs are  accumulated  in a separate  Ameren  subsidiary,
Ameren Services, which provides a variety of support services to us. We evaluate
the  performance  of our  segments  and  allocate  resources  to them,  based on
revenues and operating income.

     Segment  information  for the three and six months  ended June 30, 2003 and
2002 was as follows:

--------------------------------------------------------------------------------
                                       Electric        Gas            Total
--------------------------------------------------------------------------------
Three months ended June 30, 2003
--------------------------------------------------------------------------------
Revenues                                $ 137         $  30          $  167
Operating income                            9             -               9
--------------------------------------------------------------------------------
Three months ended June 30, 2002
--------------------------------------------------------------------------------
Revenues                                $ 161         $  26          $  187
Operating income                           11             -              11
--------------------------------------------------------------------------------
Six months ended June 30, 2003
--------------------------------------------------------------------------------
Revenues                                $ 269         $ 107          $  376
Operating income                           12             4              16
--------------------------------------------------------------------------------
Six months ended June 30, 2002
--------------------------------------------------------------------------------
Revenues                                $ 311         $  91          $  402
Operating income                           10             4              14
--------------------------------------------------------------------------------


                                       13
<PAGE>

ITEM 2. Management's  Discussion and Analysis of Financial Condition and Results
of Operations.

OVERVIEW

     Central  Illinois  Public Service  Company,  headquartered  in Springfield,
Illinois,  operates as  AmerenCIPS  and is a  wholly-owned  subsidiary of Ameren
Corporation (Ameren). Our principal business is the rate-regulated  transmission
and  distribution  of  electricity  and  the  distribution  of  natural  gas  to
residential, commercial, industrial and wholesale users in Illinois. Ameren is a
public  utility  holding  company  registered  with the  Securities and Exchange
Commission  (SEC) under the Public Utility  Holding  Company Act of 1935 (PUHCA)
and is headquartered in St. Louis, Missouri.  Ameren's principal business is the
generation, transmission and distribution of electricity and the distribution of
natural gas to  residential,  commercial,  industrial and wholesale users in the
central United States.  In addition to us, Ameren's  principal  subsidiaries and
our affiliates are as follows:

o    Union  Electric   Company,   which  operates  a   rate-regulated   electric
     generation,  transmission and distribution  business,  and a rate-regulated
     natural gas distribution business in Missouri and Illinois as AmerenUE.
o    Central  Illinois  Light Company,  a subsidiary of CILCORP Inc.  (CILCORP),
     which operates a  rate-regulated  electric  transmission  and  distribution
     business, an electric generation business and a rate-regulated  natural gas
     distribution  business in Illinois as  AmerenCILCO.  Ameren  completed  its
     acquisition  of CILCORP on January 31, 2003. See  Acquisitions  for further
     information.
o    AmerenEnergy  Resources Company (Resources Company),  which consists of non
     rate-regulated  operations.  Subsidiaries include  AmerenEnergy  Generating
     Company (Generating  Company),  which operates non rate-regulated  electric
     generation  in  Missouri  and  Illinois,   AmerenEnergy  Marketing  Company
     (Marketing  Company),  which markets power for periods  primarily  over one
     year,  AmerenEnergy  Fuels and Services  Company,  which  procures fuel and
     manages the related risks for Ameren-affiliated companies, and AmerenEnergy
     Medina  Valley Cogen  (No.4),  LLC,  which  indirectly  owns a 40 megawatt,
     gas-fired electric  generation plant. On February 4, 2003, Ameren completed
     its acquisition of AES Medina Valley Cogen (No. 4), LLC (Medina Valley) and
     renamed it AmerenEnergy  Medina Valley Cogen (No. 4), LLC. See Acquisitions
     for further  information.  Generating  Company  supplies  electric power to
     Marketing  Company  which,  in turn,  supplies  us with power under a power
     supply agreement (Power Supply Agreement).
o    AmerenEnergy,  Inc.  (AmerenEnergy),  which serves as a power marketing and
     risk management agent for  Ameren-affiliated  companies for transactions of
     primarily less than one year.
o    Electric  Energy,  Inc.  (EEI),  which  operates  electric  generation  and
     transmission facilities in Illinois. Ameren has a 60% ownership interest in
     EEI.
o    Ameren Services  Company (Ameren  Services),  which provides shared support
     services to Ameren and its  subsidiaries,  including us.  Charges are based
     upon the actual  costs  incurred  by Ameren  Services,  as  required by the
     PUHCA.

     You should read the following discussion and analysis in conjunction with:
o    The  financial  statements  and related  notes  included in this  Quarterly
     Report on Form 10-Q.
o    The financial statements and related notes included in our Quarterly Report
     on Form 10-Q for the period ended March 31, 2003.
o    Management's  Discussion and Analysis of Financial Condition and Results of
     Operations  that is included in our 2002 Annual Report on Form 10-K for the
     period ended December 31, 2002, as amended by Form 10-K/A.
o    The audited financial statements and related notes that are included in our
     2002 Annual Report on Form 10-K for the period ended  December 31, 2002, as
     amended by Form 10-K/A.

     When we refer to  AmerenCIPS,  our, we or us, we are  referring  to Central
Illinois  Public  Service  Company.  All tabular dollar amounts are in millions,
unless otherwise indicated.

     Our results of  operations  and  financial  position  are  impacted by many
factors.  Weather,  economic  conditions,  and the actions of key  customers  or
competitors can  significantly  impact the demand for our services.  Our results
are also impacted by seasonal  fluctuations  caused by winter heating and summer
cooling demand.  With nearly all of our revenues  directly subject to regulation
by various  state and  federal  agencies,  decisions  by  regulators  can have a
material impact on the price we charge for our services. We

                                       14

<PAGE>

principally utilize electric power and natural gas in our operations. The prices
for these commodities can fluctuate  significantly due to the world economic and
political  environment,  weather  and  many  other  factors.  We do  not  have a
purchased  power  recovery  mechanism  in  Illinois  for  our  electric  utility
business,  but we do have a gas  cost  recovery  mechanism  for our gas  utility
business.  In addition,  our electric  rates in Illinois are largely set through
2006. Fluctuations in interest rates impact our cost of borrowings,  and pension
and post-retirement  benefits.  We employ various risk management  strategies in
order to try to reduce our exposure to commodity  risks and other risks inherent
in our business.  The reliability of our transmission and distribution  systems,
and the level of operating and  administrative  costs and capital investment are
key  factors  that we seek to  control  in  order to  optimize  our  results  of
operations, cash flows and financial position.

Acquisitions

     On  January  31,  2003,  Ameren  completed  its  acquisition  of all of the
outstanding  common  stock of CILCORP from The AES  Corporation.  CILCORP is the
parent company of Peoria,  Illinois-based  Central Illinois Light Company, which
operated  as  CILCO.  With the  acquisition,  CILCO  became an  indirect  Ameren
subsidiary, but remains a separate utility company, operating as AmerenCILCO. On
February 4, 2003,  Ameren also  completed its  acquisition  of AES Medina Valley
Cogen  (No.  4),  LLC  (Medina  Valley)  which  indirectly  owns a 40  megawatt,
gas-fired electric generation plant. With the acquisition,  Medina Valley, which
Ameren  renamed  AmerenEnergy  Medina  Valley  Cogen  (No.  4),  LLC,  became  a
wholly-owned  subsidiary of Resources  Company.  The results of  operations  for
CILCORP and  AmerenEnergy  Medina  Valley  Cogen (No.  4), LLC were  included in
Ameren's  consolidated  financial  statements  effective  with the  January  and
February 2003 acquisition dates. Our results of operations for the three and six
months ended June 30, 2003 were not impacted by these acquisitions.

     Ameren  acquired  CILCORP  to  complement  its  existing  Illinois  gas and
electric operations.  The purchase included CILCO's rate-regulated  electric and
natural gas  businesses in Illinois  serving  approximately  200,000 and 205,000
customers, respectively, of which approximately 150,000 are combination electric
and gas  customers.  CILCO's  service  territory  is  contiguous  to our service
territory.  CILCO  also  has a non  rate-regulated  electric  and gas  marketing
business  principally  focused in the Chicago,  Illinois  region.  Finally,  the
purchase included approximately 1,200 megawatts of largely coal-fired generating
capacity, most of which is expected to become non rate-regulated in 2003.

     The total acquisition cost was approximately  $1.4 billion and included the
assumption of CILCORP and Medina  Valley debt and preferred  stock at closing of
$895 million and  consideration  of $489 million in cash,  net of cash acquired.
The cash  component  of the  purchase  price  came from  Ameren's  issuances  in
September  2002 of 8.05 million  common shares and its issuance in early 2003 of
an additional 6.325 million common shares which together generated aggregate net
proceeds of $575 million.


RESULTS OF OPERATIONS

Earnings Summary

     Our net income  decreased to $3 million in the second  quarter of 2003 from
$8 million in the second quarter of 2002. The principal  reason for the decrease
in net income was milder  weather in our service  territory ($5 million,  net of
taxes) which reduced electric and gas margins. The negative impact of weather on
electric and gas margins was partially offset by increased  interchange revenues
($1 million,  net of taxes) and decreased interest expense related to lower long
term debt levels ($1 million, net of taxes).

     Our net income decreased to $5 million in the first six months of 2003 from
$10 million in the first six months of 2002. In addition to the items  discussed
above,  net income for the first six months of 2003 benefited from favorable gas
margins, primarily due to increased demand, resulting from colder winter weather
in early 2003.  The  favorable  gas margins in the first six months of 2003 were
partially offset by a decline in the amount of intercompany interest we received
on the Generating  Company  subordinated  promissory note resulting from a lower
principal balance outstanding ($1 million, net of taxes).

                                       15
<PAGE>

Electric Operations

     The following  table  represents the favorable  (unfavorable)  variation on
electric  margins  for the three and six  months  ended  June 30,  2003 from the
comparable periods in 2002:

--------------------------------------------------------------------------------
                                                    Three Months    Six Months
--------------------------------------------------------------------------------
Electric Revenues:
    Effect of weather (estimate)                      $  (8)           $  (3)
    Interchange revenues                                  2                -
    Growth and other (estimate)                         (18)             (39)
--------------------------------------------------------------------------------
Total variation in electric operating revenues        $ (24)           $ (42)
Purchased power variation:                            $  19            $  38
--------------------------------------------------------------------------------
Change in electric margin                             $  (5)           $  (4)
--------------------------------------------------------------------------------

     Electric  margins  decreased $5 million for the three months ended June 30,
2003 and $4 million for the six months ended June 30, 2003  compared to the same
periods  in 2002  principally  due to  cooler-than-normal  weather in the second
quarter versus  warmer-than normal conditions in the same period in 2002. We had
53% less cooling  degree days in the second  quarter which resulted in decreases
in residential (18%) and commercial (25%) sales for the three months ending June
30, 2003. However, colder winter weather benefited electric margins in the first
quarter of 2003,  reducing  the net impact of weather on the first six months of
2003 as compared to the same period in 2002.

     Commencing  in  2002,  all  of our  Illinois  residential,  commercial  and
industrial  customers  had  choice in  electric  suppliers  as  provided  by the
Electric  Service  Customer  Choice  and Rate  Relief Law of 1997.  Since  then,
several  commercial and industrial  customers have switched to Marketing Company
for  their  energy  supply  resulting  in  a  decline  in  our  revenues  and  a
corresponding  decrease in purchased power of approximately  $23 million for the
three  months  ended June 30, 2003 and $42 million for the six months ended June
30, 2003. We continue to provide  electric  delivery  service to these customers
and charge them Illinois  Commerce  Commission  (ICC) approved  delivery service
tariff rates for that service.

Gas Operations

     Our gas margins  decreased  $2 million for the three  months ended June 30,
2003 compared to the same period in 2002 primarily due to  unfavorable  weather.
We had 10% less  heating  degree days for our service  territory  for the second
quarter of 2003.  For the first six months of 2003 compared to 2002, gas margins
increased  $1  million  compared  to the same  period in 2002  primarily  due to
increased  customer  demand  resulting  from colder winter  weather in the first
quarter of 2003.

Other Operating Expenses

Other Operations and Maintenance

     Other  operations  and  maintenance  expenses  decreased $2 million for the
three  months and  decreased  $1 million for the six months ended June 30, 2003,
compared  to  the  same  periods  in  2002,  primarily  due  to  a  decrease  in
professional services expenses.

     Costs of support  services  provided by Ameren  Services,  including wages,
employee benefits and professional  services, are based on actual costs incurred
and were included in other  operations and  maintenance  expenses.  See Note 3 -
Related Party Transactions to our Financial Statements under Item 1 of Part I of
this report for further information.

Depreciation and Amortization

     Depreciation and amortization expenses were comparable for the three months
ended  June 30,  2003  compared  to the same  period in 2002.  For the first six
months of 2003,  depreciation and amortization  increased $1 million compared to
the  same   period  in  2002   primarily   resulting   from   transmission   and
distribution-related additions.


                                       16
<PAGE>

Income Taxes

     Income  taxes  decreased $1 million for both the three and six months ended
June 30, 2003 compared to the prior year periods  primarily due to lower pre-tax
income.

Other Taxes

     Other taxes  increased  $1 million for the three and six months  ended June
30,  2003  compared to the same  periods in 2002 due to tax refunds  received in
2002.

Other Income and Deductions

     Other income and deductions  (excluding  income taxes) decreased $1 million
for the three  months  ended June 30, 2003  compared to the same period in 2002,
primarily  due  to a  decrease  in  contributions  in aid  of  construction  ($1
million).  For the six months ended June 30, 2003,  other income and  deductions
decreased  $4 million  compared to the same period in 2002,  primarily  due to a
decline  in  intercompany   interest  we  received  on  the  Generating  Company
subordinated  promissory note resulting from lower principal balance outstanding
($2 million) as well as a decrease in  contributions  in aid of construction ($2
million).

Interest

     Interest  expense  decreased $1 million for the three months ended June 30,
2003 and $2 million for the six months ended June 30, 2003  compared to the same
periods  in 2002,  primarily  due to less  interest  expense  as a result of the
redemption  of first  mortgage  bonds in the  third  quarter  of 2002 and in the
second quarter of 2003. See Note 5 - Debt Financings to our Financial Statements
under Item 1 of Part I of this report for further information.


LIQUIDITY AND CAPITAL RESOURCES

Operating

     Cash  provided  by  operating  activities  was $57 million in the first six
months of 2003  compared  to $15  million in the first six  months of 2002.  The
increase was primarily due to variations in working capital between the periods.

     Our tariff-based  gross margins continue to be our principal source of cash
from operating activities. Our diversified retail customer mix of rate-regulated
residential,  commercial and  industrial  classes and a commodity mix of gas and
electric  service  provide a  reasonably  predictable  source of cash flows.  In
addition,  we plan to utilize  short-term debt to support normal  operations and
other temporary capital requirements.

Investing

     Our net cash provided by investing  activities  was $40 million for the six
months ended June 30, 2003  compared to $17 million for the same period in 2002.
Cash provided by investing  activities increased in the first six months of 2003
as a result of principal  payments  received on our intercompany note receivable
with Generating  Company  coupled with a decrease in construction  expenditures.
Capital  expenditures for transmission and distribution  related  activities are
expected to approximate $55 million in 2003.

Financing

     Our cash flows used in  financing  activities  were $96 million for the six
months  ended June 30,  2003 as  compared  to $38 million for the same period in
2002. Our principal financing  activities for the six-month periods included the
payment of dividends and the redemption of long-term debt.


                                       17
<PAGE>

     We are  authorized by the SEC under the PUHCA to have up to $250 million of
short-term unsecured debt instruments outstanding at any time.

Debt Issuances and Redemptions

     On April 1, 2003,  we repaid $40  million of first  mortgage  bonds  6.375%
Series Z which matured on that date.  We also  redeemed in April 2003,  prior to
maturity and at par, our $50 million first mortgage bonds 7.5% Series X due July
1, 2007.

Short-Term Debt and Liquidity

     Short-term  debt  typically  consists of  intercompany  borrowings  through
Ameren's  utility money pool. At June 30, 2003,  Ameren and its subsidiaries had
committed credit  facilities,  expiring at various dates through 2005,  totaling
$772 million, excluding AmerenCILCO facilities of $59 million, EEI facilities of
$41 million and AmerenUE's  nuclear fuel lease facilities of $120 million.  This
amount  includes  $757  million of  committed  credit  facilities  at Ameren and
AmerenUE and $15 million of our committed bank lines of credit.  We access these
combined  facilities  through Ameren's utility money pool arrangement.  AmerenUE
and Ameren  Services  may also  borrow  under this  arrangement.  Subject to the
receipt of regulatory  approval,  which is being pursued,  AmerenCILCO will also
participate  in the  utility  money pool  arrangement.  These  committed  credit
facilities  are also used to  support  Ameren's  commercial  paper  program  and
AmerenUE's commercial paper program, under which $177 million was outstanding at
June 30, 2003.  At June 30, 2003,  $595 million was unused and  available  under
these committed credit facilities.

     In July  2003,  Ameren  entered  into two new  credit  agreements  for $470
million  in  revolving  credit  facilities  to be  used  for  general  corporate
purposes,  including the support of commercial paper programs.  The $470 million
in new facilities  includes a $235 million 364-day revolving credit facility and
a $235 million three-year revolving credit facility. These new credit facilities
replaced Ameren's existing $270 million 364-day revolving credit facility, which
matured in July 2003, and a $200 million  facility,  which would have matured in
December 2003. The new credit facilities contain provisions which require Ameren
to  meet  minimum  Employee  Retirement  Income  Security  Act  (ERISA)  funding
requirements  for its pension plan.  The prior credit  facilities  included more
restrictive  provisions  related to the funded status of Ameren's  pension plan,
which are not present in the new facilities.  In addition,  in July 2003, Ameren
entered into an amendment of an existing $130 million multi-year credit facility
that similarly  modified the  ERISA-related  provisions in this  facility.  As a
result,  all of Ameren's  facilities  require it to meet minimum  ERISA  funding
requirements,  but do not otherwise limit the underfunded  status of its pension
plan. At July 31, 2003,  all of such borrowing  capacity under these  facilities
was available.

     We  rely on  access  to  short-term  and  long-term  capital  markets  as a
significant  source of funding for capital  requirements  not  satisfied  by our
operating  cash  flows.  Our  inability  to raise  capital on  favorable  terms,
particularly  during  times  of  uncertainty  in  the  capital  markets,   could
negatively impact our ability to maintain and grow our businesses.  Based on our
current credit  ratings,  we believe that we will continue to have access to the
capital markets.  However,  events beyond our control may create  uncertainty in
the capital  markets such that our cost of capital would increase or our ability
to access the capital markets would be adversely affected.

Financial Agreement Provisions and Covenants

     Our financial  agreements  and those of Ameren  include  customary  default
provisions  that could impact the continued  availability of credit or result in
the acceleration of repayment.  The majority of committed  credit  facilities of
Ameren and its  subsidiaries  require the borrower to  represent,  in connection
with any  borrowing  under the  facility  that no  material  adverse  change has
occurred since certain dates.  None of our financing  arrangements  nor those of
Ameren and its subsidiaries  contains credit rating  triggers,  except for three
funded bank term loans at AmerenCILCO totaling $105 million at June 30, 2003.

     At June 30,  2003,  Ameren  and its  subsidiaries,  including  us,  were in
compliance with their financial agreement provisions and covenants.


                                       18

<PAGE>

Off-Balance Sheet Arrangements

     At June 30, 2003,  neither Ameren,  nor any of its subsidiaries,  including
us, had any  off-balance  sheet  financing  arrangements,  other than  operating
leases entered into in the ordinary course of business.


OUTLOOK

     We believe  there will be  challenges to earnings in 2003 and beyond due to
industry-wide trends and company-specific  issues. The following are expected to
put pressure on earnings in 2003 and beyond:

o    Weak economic conditions, which impact native load demand;
o    Fixed electric rates in our Illinois service territory;
o    The adverse effects of rising employee  benefit costs and higher  insurance
     costs; and
o    An assumed return to more normal weather patterns relative to 2002.

     In late 2002, we and Ameren announced the following actions to mitigate the
effect of these challenges:

o    A voluntary  retirement  program  that was  accepted by  approximately  550
     Ameren  employees,   including   approximately  70  of  our  employees  and
     additional  employees  providing  support  functions  to us through  Ameren
     Services;
o    Modifications to retiree employee benefit plans to increase co-payments and
     limit Ameren's overall cost;
o    A wage freeze in 2003 for all management employees; and
o    Reductions of 2003 expected capital expenditures.

     We are pursuing an annual gas rate increase of approximately $16 million in
Illinois.  See Note 2 - Rate and Regulatory Matters to our Financial  Statements
under Item 1 of Part I of this report for additional information. Ameren is also
considering  additional  actions,  including  modifications  to active  employee
benefits, further staffing reductions and other initiatives.

     International Brotherhood of Electrical Workers (IBEW) labor agreements for
one bargaining  unit covering 70% of our workforce  expired  between April 1 and
July 1, 2003. The principal  issues being negotiated with regard to continuation
of these labor  agreements are wages,  work rules and our proposal to change the
employee  medical  benefit  program  to require  employees  to pay for a greater
portion of their  benefit  coverage.  Changes to the employee  medical  benefits
program have been agreed to with a joint bargaining  committee  representing all
unions;  however,  the changes cannot be implemented  without  ratification by a
majority of the collective  membership of all bargaining units. We are unable to
predict  whether  the  agreements  will be  ratified  or the  response  of other
union-represented  employees  to any action by its  employees.  We are unable to
determine  what,  if any,  impact these labor  matters  could have on our future
financial condition, results of operations or liquidity.

     At December 31, 2002,  Ameren recorded a minimum pension  liability of $102
million,   after  taxes,  which  resulted  in  a  charge  to  Accumulated  Other
Comprehensive  Income  (Loss)(OCI) and a reduction in stockholders'  equity. Our
portion of the minimum pension liability was $13 million,  after taxes. Based on
changes in interest rates,  Ameren may need to change its actuarial  assumptions
for its pension plan at December 31, 2003,  which could result in a  requirement
to record an additional minimum pension liability.

     In the ordinary course of business,  we and Ameren  evaluate  strategies to
enhance our financial  position,  results of  operations  and  liquidity.  These
strategies may include potential  acquisitions,  divestitures,  opportunities to
reduce costs or increase  revenues and other  strategic  initiatives in order to
increase Ameren's  shareholder value. We are unable to predict which, if any, of
these initiatives will be executed,  as well as the impact these initiatives may
have on our future financial position, results of operations or liquidity.

                                       19

<PAGE>

REGULATORY MATTERS

     See Note 2 - Rate and Regulatory Matters to our Financial  Statements under
Item 1 of Part I of this report for information  regarding the proposed transfer
by our affiliate  AmerenUE of their Illinois service territory to us, as well as
other regulatory matters.

ACCOUNTING MATTERS

     See Note 1 - Summary of  Significant  Accounting  Policies to our Financial
Statements under Item 1 of Part I of this report for information.


ITEM 3. Quantitative And Qualitative Disclosures About Market Risk.

     Market risk  represents the risk of changes in value of a physical asset or
a financial instrument, derivative or non-derivative,  caused by fluctuations in
market  variables  (e.g.,  interest rates,  etc.).  The following  discussion of
Ameren's risk management  activities,  including  those of AmerenCIPS,  includes
"forward-looking"  statements  that  involve  risks  and  uncertainties.  Actual
results could differ  materially from those  projected in the  "forward-looking"
statements. Ameren handles market risks in accordance with established policies,
which may include entering into various derivative  transactions.  In the normal
course of  business,  Ameren  and our  company  also face  risks that are either
non-financial or  non-quantifiable.  Such risks  principally  include  business,
legal and operational risks and are not represented in the following discussion.

     Ameren's risk management  objective is to optimize its physical  generating
assets within prudent risk  parameters.  Risk  management  policies are set by a
Risk Management  Steering  Committee,  which is comprised of senior-level Ameren
officers.

Interest Rate Risk

     We are exposed to market risk through changes in interest rates  associated
with both long-term and short-term  variable-rate  debt and fixed-rate debt, and
auction-rate   preferred   stock.  We  manage  our  interest  rate  exposure  by
controlling   the  amount  of  these   instruments  we  hold  within  our  total
capitalization  portfolio  and by  monitoring  the effects of market  changes in
interest rates.

     Utilizing  our  debt  outstanding  at June  30,  2003,  if  interest  rates
increased by 1%, our annual  interest  expense and dividends on preferred  stock
would  increase  by less than $1 million and net income  would  decrease by less
than $1 million. The model does not consider the effects of the reduced level of
potential overall economic activity that would exist in such an environment.  In
the event of a significant  change in interest  rates,  management  would likely
take actions to further mitigate our exposure to this market risk. However,  due
to the  uncertainty  of the  specific  actions  that  would be taken  and  their
possible  effects,  the sensitivity  analysis assumes no change in our financial
structure.

Equity Price Risk

     AmerenCIPS,  along with other  subsidiaries of Ameren,  is a participant in
Ameren's defined benefit and  post-retirement  benefit plans and are responsible
for  our  proportional   share  of  the  costs.   Ameren's  costs  of  providing
non-contributory  defined benefit retirement and  post-retirement  benefit plans
are  dependent  upon a number  of  factors,  such as the rates of return on plan
assets,   discount  rate,  the  rate  of  increase  in  health  care  costs  and
contributions  made to the plans.  The market value of Ameren's  plan assets has
been  affected by declines in the equity  market  since 2000 for the pension and
post-retirement  plans.  As a result,  at  December  31,  2002,  Ameren  and its
subsidiaries,  including us, recognized an additional  minimum pension liability
as  prescribed  by SFAS  No.  87,  "Employers'  Accounting  for  Pensions."  The
liability  resulted in a reduction to equity as a result of a charge to Ameren's
OCI of $102  million,  net of taxes.  Our  portion of this charge to OCI was $13
million,  net of taxes.  The  amount of the  liability  was the  result of asset
returns experienced  through 2002, interest rates and Ameren's  contributions to
the plans during 2002. The minimum pension

                                       20

<PAGE>

liability  did not  change at June 30,  2003.  In future  years,  the  liability
recorded,  the costs reflected in net income,  or OCI, or cash  contributions to
the plans could  increase  materially  without a recovery  in equity  markets in
excess of Ameren's assumed return on plan assets.  If the fair value of the plan
assets  were to grow and  exceed  the  accumulated  benefit  obligations  in the
future, then the recorded liability would be reduced and a corresponding  amount
of equity would be restored in the Balance Sheet.

ITEM 4.  Controls and Procedures.

    (a) Evaluation of Disclosure Controls and Procedures

     As of  June  30,  2003,  the  principal  executive  officer  and  principal
financial  officer of AmerenCIPS have evaluated the  effectiveness of the design
and operation of AmerenCIPS'  disclosure  controls and procedures (as defined in
Rules  13a-15(e) and 15d-15(e) of the Securities and Exchange  Commission Act of
1934, as amended  (Exchange  Act)).  Based upon that  evaluation,  the principal
executive  officer and principal  financial officer of AmerenCIPS have concluded
that such  disclosure  controls and procedures are effective in timely  alerting
them to any material information relating to AmerenCIPS, which is required to be
included  in  AmerenCIPS'  reports  filed or  submitted  with the SEC  under the
Exchange Act.

     (b) Change in Internal Controls

     There has been no significant  change in AmerenCIPS'  internal control over
financial  reporting that occurred during AmerenCIPS' most recent fiscal quarter
that has  materially  affected,  or is reasonably  likely to materially  affect,
AmerenCIPS' internal control over financial reporting.

FORWARD-LOOKING STATEMENTS

     Statements made in this report 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,  we are  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  report  and  in  subsequent
securities  filings and others,  could cause results to differ  materially  from
management expectations as suggested by such "forward-looking" statements:

o    the effects of regulatory actions, including changes in regulatory policy;
o    changes in laws and other  governmental  actions,  including  monetary  and
     fiscal policies;
o    the impact on us of current  regulations  related  to the  opportunity  for
     customers to choose alternative energy suppliers in Illinois;
o    delays in or  difficulties  in  connection  with the receipt of  regulatory
     approvals  with respect to AmerenUE's  plan to  discontinue  operating as a
     public utility subject to ICC regulation and the transferring of AmerenUE's
     Illinois-based  electric  and natural gas  businesses  to us or  unexpected
     adverse conditions or terms of those approvals;
o    the  effects of  increased  competition  in the future due to,  among other
     things,  deregulation  of certain aspects of our 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 purchased power,  electricity and
     natural gas for distribution, including the use of financial and derivative
     instruments  and  volatility of changes in market prices and our ability to
     recover increased costs;
o    average rates for electricity in the Midwest;
o    business and economic conditions;
o    the impact of the adoption of new accounting  standards on the  application
     of appropriate technical accounting rules and guidance;

                                       21

<PAGE>

o    interest rates and the availability of capital;
o    actions of rating agencies and the effects of such actions;
o    weather conditions;
o    the  effects  of  strategic   initiatives,   including   acquisitions   and
     divestitures;
o    the  impact of  current  environmental  regulations  on  utilities  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  benefit costs,  including  changes in returns of
     benefit plan assets;
o    disruptions of the capital  markets or other events making Ameren's and our
     access to necessary capital more difficult or costly;
o    cost and  availability  of  transmission  capacity  required to satisfy our
     energy sales; and
o    legal and administrative proceedings.

     Given these  uncertainties,  undue  reliance  should not be placed on these
forward-looking  statements.  Except  to the  extent  required  by  the  federal
securities  laws, we undertake no  obligation  to publicly  update or revise any
forward-looking  statements,  whether  as a result  of new  information,  future
events or otherwise.


                                       22
<PAGE>


                           PART II. OTHER INFORMATION

ITEM 1.  Legal Proceedings.

     On June 18, 2003,  twenty retirees and surviving spouses of retirees of our
parent, Ameren Corporation, or its predecessors or subsidiaries (the plaintiffs)
filed a complaint in the U.S.  District  Court,  Southern  District of Illinois,
against  Ameren,  and its  subsidiaries,  Union Electric  Company,  operating as
AmerenUE,  Ameren Energy Resources  Company,  Ameren Energy Generating  Company,
Ameren Services  Company and us, and against  Ameren's Retiree Medical Plan (the
defendants).  The  retirees  were  members of various  local labor unions of the
International  Brotherhood of Electrical  Workers  (IBEW) and the  International
Union of Operating Engineers (IUOE). The complaint alleges the following:

o    the labor  organizations which represented the plaintiffs have historically
     negotiated  retiree medical  benefits with the defendants and that pursuant
     to the negotiated  collective  bargaining  agreements and other  negotiated
     documents,  the plaintiffs are guaranteed medical benefits at no cost or at
     a fixed maximum cost during their retirement;
o    Ameren has unilaterally  announced that,  beginning in 2004,  retirees must
     pay a portion of their own health care  premiums  and either an  increasing
     portion  of  their  dependents'   premiums  or  newly  imposed  dependents'
     premiums,  and that surviving  spouses will be paying increased amounts for
     their medical benefits;
o    the defendants'  actions deprive the plaintiffs of vested benefits and thus
     violate  the  Employee   Retirement  Income  Security  Act  and  the  Labor
     Management   Relations  Act  of  1947,  and  constitute  a  breach  of  the
     defendants' fiduciary duties; and
o    the defendants are estopped from changing the plan benefits.

     The  plaintiffs  have filed the  complaint on behalf of  themselves,  other
similarly situated former  non-management  employees and their surviving spouses
who retired from January 1, 1992 through  October 1, 2002,  and on behalf of all
subsequent  non-management  retirees and their  surviving  spouses  whose vested
medical  benefits are reduced or are threatened with  reduction.  The plaintiffs
seek to have this lawsuit  certified as a class  action,  injunctive  relief and
declaratory  relief,  actual  damages for any amounts  they are made to pay as a
result of the  defendants'  actions,  and payment of attorney fees and costs. On
August 11, 2003, the defendants  filed motions to dismiss  various counts of the
complaint. We are unable to predict the outcome of this lawsuit or the impact of
the outcome on our financial position, results of operations or liquidity.

     Reference is made to Note 12 to the Notes to Financial  Statements  in Item
8. "Financial  Statements and Supplementary  Data" in Part II of our 2002 Annual
Report  on Form  10-K,  to  Note 7  under  Item  8.  "Financial  Statements  and
Supplementary  Data" in Part II of the 2002  Annual  Report  on Form 10-K of our
affiliates,  CILCORP  Inc.  and Central  Illinois  Light  Company,  operating as
AmerenCILCO,  and to Item 1. "Legal Proceedings" in Part II of our Form 10-Q for
the  quarterly  period  ended March 31, 2003,  for a  discussion  of a number of
lawsuits that name our affiliates,  AmerenUE and AmerenCILCO, our parent, Ameren
Corporation,  and us (which we refer to as the  Ameren  companies),  along  with
numerous other parties as defendants that have been filed by plaintiffs claiming
varying degrees of injury from asbestos  exposure.  Since the filing of our Form
10-Q for the quarterly period ended March 31, 2003, eleven  additional  lawsuits
have been filed against the Ameren companies.  These lawsuits, like the previous
cases,  were mostly  filed in the Circuit  Court of Madison  County in Illinois,
involve a large  number of total  defendants  and seek  unspecified  damages  in
excess of $50,000  in each case,  which,  if proved,  typically  would be shared
among  the named  defendants.  Also  since  the  filing of our Form 10-Q for the
quarterly  period ended March 31, 2003,  the Ameren  companies  have settled one
case. To date, a total of 164 asbestos-related  lawsuits have been filed against
the Ameren companies,  of which 84 are pending, 17 have been settled and 63 have
been  dismissed.  Of these 164 lawsuits,  we have been  specifically  named as a
defendant in 60, of which 31 are  pending,  8 have been settled and 21 have been
dismissed.  We believe that the final  disposition of these proceedings will not
have a material adverse effect on our financial position,  results of operations
or liquidity.


                                       23
<PAGE>

     Note 2 - Rate and Regulatory Matters to our Financial Statements under Item
1 of  Part I of  this  report  contains  additional  information  on  legal  and
administrative proceedings which is incorporated by reference under this item.


ITEM 4.  Submission of Matters To a Vote of Security Holders.

     At our annual meeting of stockholders  held on April 22, 2003, the election
of  directors  was  presented  to the meeting for a vote and the results of such
voting are as follows:

                                                                      Non-Voted
       Name                                For           Withheld      Brokers
       ----                                ---           --------      -------

       Paul A. Agathen                  25,475,840         474           0
       Warner L. Baxter                 25,475,872         442           0
       Richard A. Liddy                 25,475,877         437           0
       Richard A. Lumpkin               25,475,872         442           0
       Paul L. Miller, Jr.              25,475,877         437           0
       Charles W. Mueller               25,475,802         512           0
       Douglas R. Oberhelman            25,475,801         513           0
       Gary L. Rainwater                25,475,877         437           0
       Harvey Saligman                  25,475,872         442           0
       Thomas R. Voss                   25,475,877         437           0
       David A. Whiteley                25,475,877         437           0


ITEM 5.  Other Information.

     Reference  is made to Item 2.  "Properties"  in Part I of our  2002  Annual
Report on Form 10-K for a  discussion  of our  membership  in MAIN  (Mid-America
Interconnected  Network),  which  is one of the  regional  electric  reliability
councils  organized for  coordinating the planning and operation of the nation's
bulk power supply.  In response to the withdrawal  notices filed by Commonwealth
Edison and Illinois Power,  also members of MAIN, we, along with our affiliates,
AmerenUE and  AmerenCILCO,  provided  formal written notice to the MAIN Board of
Directors on June 23, 2003 of our intent to withdraw from MAIN effective January
1, 2005. We intend to join another Regional Reliability Organization (RRO) prior
to our  withdrawal  from  MAIN  becoming  effective.  Until  our  withdrawal  is
effective, we will continue to honor all of our obligations as a member of MAIN.
If we do not join  another RRO, we may withdraw our notice of intent to withdraw
from MAIN.

     Any stockholder  proposal  intended for inclusion in the proxy material for
our 2004 annual meeting of  stockholders  must be received by us by November 28,
2003.  In  addition,  under our  By-Laws,  stockholders  who  intend to submit a
proposal in person at an annual meeting, or who intend to nominate a director at
a meeting,  must provide  advance  written  notice  along with other  prescribed
information. In general, such notice must be received by our Secretary not later
than 60 nor  earlier  than 90 days  prior to the  anniversary  of the  preceding
year's annual  meeting.  For our 2004 annual  meeting of  stockholders,  written
notice of any  in-person  stockholder  proposal or director  nomination  must be
received not later than February 22, 2004 or earlier than January 23, 2004.  Our
2004 annual meeting of stockholders is scheduled to be held on April 27, 2004.


ITEM 6.  Exhibits and Reports on Form 8-K.

     (a) Exhibits filed herewith.

          31.1 - Rule  13a-14(a)/15d-14(a)  Certification of Principal Executive
                 Officer  (required  by Section 302 of the  Sarbanes-Oxley  Act
                 of 2002).

          31.2 - Rule  13a-14(a)/15d-14(a)  Certification of Principal Financial
                 Officer  (required  by Section 302 of the  Sarbanes-Oxley  Act
                 of 2002).

                                       24

<PAGE>

          32.1 - Section  1350  Certification  of  Principal  Executive  Officer
                 (required by Section 906 of the Sarbanes-Oxley Act of 2002).

          32.2 - Section  1350  Certification  of  Principal  Financial  Officer
                 (required by Section 906 of the Sarbanes-Oxley Act of 2002).

     (b)  Reports on Form 8-K. Central Illinois Public Service Company filed the
          following  report on Form 8-K during the  quarterly  period ended June
          30, 2003:

--------------------------------------------------------------------------------
                                                 Items              Financial
                       Date of Report           Reported        Statements Filed
--------------------------------------------------------------------------------
                    May 30, 2003                   5                  None


     Note:     Reports of Ameren  Corporation on Forms 8-K, 10-Q and 10-K are on
               file with the SEC under File Number 1-14756.

               Reports of Union Electric Company on Forms 8-K, 10-Q and 10-K are
               on file with the SEC under File Number 1-2967.

               Reports of AmerenEnergy Generating Company on Forms 8-K, 10-Q and
               10-K are on file with the SEC under File Number 333-56594.

               Reports of CILCORP  Inc. on Forms 8-K,  10-Q and 10-K are on file
               with the SEC under File Number 2-95569.

               Reports of Central  Illinois Light Company on Forms 8-K, 10-Q and
               10-K are on file with the SEC under File Number 1-2732.

                                       25
<PAGE>





                                    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.

                                      CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                                                    (Registrant)

                                      By         /s/ Martin J. Lyons
                                         -------------------------------------
                                                     Martin J. Lyons
                                             Vice President and Controller
                                             (Principal Accounting Officer)
Date:  August 14, 2003



                                       26