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                                  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 Quarterly Period Ended September 30, 2000

[ ] 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     .
                                -------         ------


Shares outstanding of each of registrant's classes of common stock as of October
31, 2000: Common Stock, no par value, held by Ameren Corporation (parent company
of Registrant) - 25,452,373


<PAGE>


                     Central Illinois Public Service Company

                                      Index

                                                                        Page No.

Part I               Financial Information (Unaudited)

                     Management's Discussion and Analysis                    2

                     Quantitative and Qualitative Disclosures
                     About Market Risk                                       6

                     Balance Sheet
                     - September 30, 2000 and December 31, 1999              8

                     Statement of Income
                     - Three months, nine months and 12 months ended
                        September 30, 2000 and 1999                          9

                     Statement of Cash Flows
                     - Nine months ended September 30, 2000 and 1999        10

                     Notes to Financial Statements                          11


Part II              Other Information                                      14

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                    PART I. FINANCIAL INFORMATION (UNAUDITED)

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF
OPERATIONS

OVERVIEW

Central  Illinois  Public Service  Company  (AmerenCIPS or the  Registrant) is a
subsidiary of Ameren  Corporation  (Ameren),  a holding company registered under
the Public Utility Holding Company Act of 1935 (PUHCA).  In December 1997, Union
Electric Company  (AmerenUE) and CIPSCO  Incorporated  (CIPSCO) combined to form
Ameren,  with  AmerenUE and CIPSCO's  subsidiaries,  the  Registrant  and CIPSCO
Investment Company (CIC), becoming subsidiaries of Ameren (the Merger).

On May 1,  2000,  following  the  receipt  of all  required  State  and  Federal
regulatory approvals,  the Registrant transferred its electric generating assets
and liabilities,  at historical net book value, to a newly created  nonregulated
company,  AmerenEnergy  Generating Company (Generating Company), a subsidiary of
AmerenEnergy Resources Company (Resources Company), a wholly-owned subsidiary of
Ameren (the  Transfer).  Discussion  below under Results of Operations  reflects
that as a result of the Transfer,  from May 1, 2000 interchange  sales and sales
under  certain  wholesale   contracts  are  no  longer  being  included  in  the
Registrant's  operating  revenues  and that  operating  expenses  include  those
expenses  it  incurs  under  its  traditional   transmission   and  distribution
operations,  as well as purchased power under an electric power supply agreement
with Resources  Company's newly created  marketing  subsidiary (the Power Supply
Agreement).  See  Electric  Industry  Restructuring  and  Note 1 under  Notes to
Financial Statements for further discussion.

The following  discussion and analysis  should be read in  conjunction  with the
Notes  to  Financial  Statements  beginning  on page  11,  and the  Management's
Discussion and Analysis of Financial Condition and Results of Operations (MD&A),
the Audited Financial Statements and the Notes to Financial Statements appearing
in the Registrant's 1999 Form 10-K.

RESULTS OF OPERATIONS

Earnings
Third  quarter 2000  earnings of $31 million  decreased  $12 million from 1999's
third quarter  earnings.  Earnings for the nine months ended  September 30, 2000
were comparable to the preceding  nine-month period.  Earnings for the 12 months
ended  September  30, 2000 were $50  million,  a $34 million  decrease  from the
preceding 12-month period.

Earnings  fluctuated due to many conditions,  primarily:  sales growth,  weather
variations,  electric  rate  reductions,  the  Transfer,  a gas  rate  increase,
competitive  market forces,  fluctuating  operating  costs,  changes in interest
expense,  changes in income and property  taxes and  nonrecurring  charges for a
targeted employee separation plan and for coal contract termination payments.

The  significant  items  affecting  revenues,  costs  and  earnings  during  the
three-month,  nine-month and 12-month  periods ended September 30, 2000 and 1999
are detailed below.

Electric Operations

Electric Operating Revenues      Variations for periods ended September 30, 2000
                                         from comparable prior-year periods
-------------------------------------------------------------------------------
(Millions of Dollars)           Three Months    Nine Months    Twelve Months
                                ------------    -----------    -------------
-------------------------------------------------------------------------------
Credit to customers              $        8      $        8     $         16
Effect of abnormal weather              (14)            (17)             (18)
Growth and other                          -              20               22
Interchange sales                       (58)            (59)             (42)
-------------------------------------------------------------------------------
                                 $      (64)     $      (48)    $        (22)
-------------------------------------------------------------------------------

Electric  revenues for the three months ended September 30, 2000,  decreased $64
million compared to the prior three-month  period primarily due to a decrease in
interchange sales, which are now being recorded at Resources Company as a result
of the Transfer.  In addition,  sales under certain  wholesale  contracts are no
longer being included in the Registrant's  operating revenues as a result of the
Transfer.  Electric  revenues were also reduced by a decline in residential  and
commercial sales of 8 percent and 4 percent, respectively, resulting from

                                       -2-

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milder weather.  These decreases were partially  offset by a 37 percent increase
in  industrial  sales,  resulting  primarily  from a new  contract  with a large
industrial customer.

Electric  revenues for the nine months and 12 months ended  September  30, 2000,
decreased $48 million and $22 million, respectively,  compared to the same prior
year periods primarily due to a decrease in interchange sales as a result of the
Transfer. Electric revenues were also reduced by a decrease in residential sales
of 4 percent and 3 percent,  respectively,  resulting from milder weather. These
decreases were offset in part by an increase in wholesale and industrial sales.

Fuel and Purchased Power        Variations for periods ended September 30, 2000
                                        from comparable prior-year periods
--------------------------------------------------------------------------------
(Millions of Dollars)                 Three Months   Nine Months   Twelve Months
                                      ------------   -----------   -------------
--------------------------------------------------------------------------------
Fuel:
    Generation                           $  (51)       $  (70)        $  (61)
    Price                                     -            (6)            (8)
    Generation efficiencies and other         -            (4)            (7)
    Coal contract termination payments        -             -             52
Purchased power                              73           140            143
--------------------------------------------------------------------------------
                                         $   22        $   60         $  119
--------------------------------------------------------------------------------

Fuel and  purchased  power costs for the three months ended  September  30, 2000
increased $22 million versus the same period in the prior year, primarily due to
an overall net increase in  purchased  power costs under the  provisions  of the
Power Supply Agreement entered into as part of the Transfer.

Fuel and  purchased  power costs for the nine months  ended  September  30, 2000
increased  $60 million  compared to the prior year period,  primarily  due to an
overall net increase in generation  and purchased  power  resulting  from higher
native sales and higher  purchased power costs under the provisions of the Power
Supply Agreement entered into as part of the Transfer, partially offset by lower
fuel prices.

The $119 million  increase in fuel and  purchased  power costs for the 12 months
ended  September 30, 2000 versus the prior-year  period was primarily the result
of an overall net increase in generation  and purchased  power,  resulting  from
higher sales volume and higher purchased power costs under the provisions of the
Power Supply Agreement  entered into as part of the Transfer,  and coal contract
termination payments, partially offset by lower fuel prices.

Gas Operations
Gas revenues for the  three-month  and  nine-month  periods ended  September 30,
2000,  increased  $4  million  and $8  million,  respectively,  compared  to the
year-ago  periods  primarily  due to higher  gas  costs  recovered  through  the
Registrant's  purchased gas  adjustment  clause,  partially  offset by decreased
retail  sales of 2 percent and 5 percent,  respectively.  Gas  revenues  for the
12-month period ended  September 30, 2000 increased $16 million  compared to the
same year-ago period primarily due to a gas rate increase which became effective
in  February  1999 and  higher  gas costs  recovered  through  the  Registrant's
purchased gas adjustment  clause.  These increases were partially  offset by a 6
percent  decline in retail sales,  as well as a decrease in off-system  sales to
others.

Gas costs for the  three-month,  nine-month and 12-month periods ended September
30,  2000,  increased  $3  million,  $4 million and $11  million,  respectively,
compared to the year-ago periods  primarily due to higher gas prices,  partially
offset by lower retail sales.

Other Operating Expenses
Other operating expense variations  reflected  recurring factors such as growth,
inflation, the Transfer and labor and benefit decreases, in addition to a charge
for the targeted employee separation plan.

Other  operations  expenses  decreased $28 million and $43 million for the three
months and nine months ended September 30, 2000,  respectively,  compared to the
same  year-ago  periods  primarily  due to lower  employee  benefit  costs and a
reduced  workforce  resulting  from  the  Transfer.  Other  operations  expenses
decreased $39 million for the 12 months ended  September  30, 2000,  compared to
the same year-ago period,  primarily due to a reduced  workforce  resulting from
the  Transfer,  coupled with the fact that  expenses for the twelve months ended
September  30,  1999  included  a  nonrecurring  pretax  charge  for a  targeted
separation plan of $7 million. These decreases were partially offset by expenses
associated with  deregulation in Illinois and the Year 2000 computer  compliance
project.

                                       -3-

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Maintenance  expenses  for the three  months,  nine  months and 12 months  ended
September  30,  2000  decreased  $17  million,  $32  million  and  $17  million,
respectively,  from  the  comparable  year-ago  periods.  These  decreases  were
primarily the result of decreased  power plant  maintenance  resulting  from the
Transfer.

Taxes
Income  taxes for the three  months  and 12 months  ended  September  30,  2000,
decreased  $5 million  and $14  million,  respectively,  primarily  due to lower
pretax  income.  Income  taxes for the nine months  ended  September  30,  2000,
increased $4 million, primarily due to a higher effective tax rate.

Other taxes for the three months ended  September 30, 2000  decreased $4 million
primarily due to lower property  taxes as a result of the Transfer.  Other taxes
for the 12 months ended September 30, 2000 decreased $3 million primarily due to
lower property taxes as a result of the Transfer and a decrease in gross receipt
taxes,  resulting  from the  restructuring  of the Illinois  public  utility tax
whereby gross receipt taxes are no longer recorded as electric revenue and gross
receipt tax expense. These decreases were partially offset by increased property
taxes as a result of higher estimated assessment values.

Other Income and Deductions
For the three  months,  nine  months and 12 months  ended  September  30,  2000,
miscellaneous,   net  increased  $10  million,  $16  million  and  $17  million,
respectively,  compared  to same  year-ago  periods,  primarily  due to interest
income earned on the promissory note receivable from Generating  Company as part
of the Transfer.  See Electric Industry  Restructuring and Note 1 under Notes to
Financial Statements for further discussion of the promissory note.

Balance Sheet
The $5 million  increase in trade accounts  receivable and unbilled  revenue was
primarily  due to higher  revenues  in August and  September  2000  compared  to
November and December 1999.

The decrease in property and plant,  net and the increase in intercompany  notes
receivable  and  intercompany  tax  receivable  were  due to the  Transfer.  See
Electric Industry  Restructuring and Note 1 under Notes to Financial  Statements
for further discussion.

Changes in accounts and wages payable,  taxes accrued,  other accounts and notes
receivable,  and other  current  assets  resulted  from the  timing  of  various
payments to taxing authorities and suppliers.

LIQUIDITY AND CAPITAL RESOURCES

Cash provided by operating  activities  totaled $139 million for the nine months
ended September 30, 2000, compared to $163 million during the same 1999 period.

Cash flows used in investing  activities totaled $31 million and $81 million for
the nine months ended  September 30, 2000 and 1999,  respectively.  Construction
expenditures  for the nine months ended September 30, 2000, for constructing new
or improving existing facilities,  were $31 million.  Construction  expenditures
decreased from the prior period due to the effects of the Transfer. See Electric
Industry  Restructuring  and Note 1 under  Notes  to  Financial  Statements  for
further discussion.

Cash flows used in financing activities totaled $100 million for the nine months
ended  September 30, 2000,  compared to $72 million during the same 1999 period.
The  Registrant's  principal  financing  activities for the period  included the
redemption of long-term debt, the payment of intercompany  notes payable and the
payment of dividends, partially offset by the issuance of long-term debt.

Subject  to certain  approvals,  the  Registrant  intends  to  transfer  primary
liability for $104 million of tax-exempt  pollution  control loan obligations to
Generating  Company during the first quarter of 2001. Upon the transfer of these
obligations to Generating Company,  the amount of Generating Company's liability
to the Registrant  under the promissory note issued as part of the Transfer will
be reduced by a like amount. The pollution control loan obligations  referred to
above  have  maturity  dates  ranging  from  2014 to 2028 and bear  interest  at
variable rates.

The Registrant  plans to continue  utilizing  short-term  debt to support normal
operations and other temporary requirements. The Registrant is authorized by the
Securities and Exchange  Commission (SEC) under PUHCA to have up to $250 million
of short-term unsecured debt instruments outstanding at any one time. Short-term
borrowings  consist of bank loans  (maturities  generally on an overnight basis)
and commercial  paper  (maturities  generally within 1 to 45 days). At September
30, 2000, the Registrant had committed bank lines of credit

                                       -4-

<PAGE>

aggregating  $25 million  (all of which was unused and  available  at such date)
which make  available  interim  financing at various rates of interest  based on
LIBOR,  the bank  certificate  of deposit  rate or other  options.  The lines of
credit are renewable annually at various dates throughout the year. At September
30, 2000, the Registrant had no outstanding short-term borrowings.

Also, the Registrant has the ability to borrow up to approximately  $950 million
from Ameren or AmerenUE through a regulated money pool agreement.  The regulated
money pool was established to coordinate and provide for certain short-term cash
and working capital requirements and is administered by Ameren Services Company,
another  subsidiary  of Ameren.  Interest  is  calculated  at  varying  rates of
interest  depending on the  composition  of internal  and external  funds in the
regulated  money pool. At September 30, 2000, the Registrant had $126 million of
intercompany  borrowings  outstanding  and $484  million  available  through the
regulated money pool.

The Registrant,  in the ordinary course of business,  explores  opportunities to
reduce  its costs in order to remain  competitive  in the  marketplace.  An area
where the Registrant  focuses its review includes,  but is not limited to, labor
costs. In the labor area, the Registrant has reached  agreements with all of the
Registrant's  major  collective  bargaining units which will permit it to manage
its labor costs and practices  effectively in the future.  The  Registrant  also
explores  alternatives  to effectively  manage the size of its workforce.  These
alternatives include utilizing hiring freezes, outsourcing and offering employee
separation packages.

Certain of these cost reduction alternatives could require nonrecurring payments
of employee separation benefits. Management is unable to predict which (if any),
and to what extent, these alternatives to reduce its overall cost structure will
be executed.  Management  is unable to determine  the impact of these actions on
the Registrant's future financial position, results of operations or liquidity.

REGULATORY MATTERS

In September 2000, the Registrant and its affiliate,  AmerenUE,  filed a request
with the Illinois  Commerce  Commission (ICC) seeking  authorization to transfer
AmerenUE's   Illinois-based   electric  and  natural  gas   busineses   and  its
Illinois-based  distribution  and  transmission  assets  and  personnel  to  the
Registrant.  The distribution and  transmission  assets and related  liabilities
will be transferred from AmerenUE to the Registrant at historical net book value
of  approximately  $100  million.  In  connection  with  this  transaction,  the
Registrant  will issue a subordinated  intercompany  note payable to AmerenUE of
approximately $50 million.  The balance of the assets will be transferred to the
Registrant  in the form of a capital  contribution.  In October  2000,  AmerenUE
filed a requestwith the Missouri  Public Service  Commission for approval of the
transfer.  The transfer is also subject to  regulatory  filings and approvals of
the Federal Energy Regulatory Commission (FERC), the SEC and the ICC.


ELECTRIC INDUSTRY RESTRUCTURING

In December 1997, the Governor of Illinois signed the Electric  Service Customer
Choice and Rate  Relief Law of 1997 (the Law)  providing  for  electric  utility
restructuring  in Illinois.  This  legislation  introduces  competition into the
supply of electric energy at retail in Illinois.

One of the major  provisions of the Law includes the phasing-in  through 2002 of
retail direct access, which allows customers to choose their electric generation
supplier.  The phase-in of retail direct  access began on October 1, 1999,  with
large  commercial and industrial  customers  principally  comprising the initial
group.  The customers in this group  represent  approximately  24 percent of the
Registrant's  total sales. As of September 30, 2000, the impact of retail direct
access  on the  Registrant's  financial  condition,  results  of  operations  or
liquidity was immaterial.  Retail direct access will be offered to the remaining
commercial  and  industrial  customers on December 31, 2000,  and to residential
customers on May 1, 2002.

The Transfer
In conjunction with another provision of the Law, on May 1, 2000,  following the
receipt of all required State and Federal regulatory  approvals,  the Registrant
transferred its electric  generating  assets and liabilities,  at historical net
book value, to a newly created  nonregulated  company,  AmerenEnergy  Generating
Company (Generating Company), a subsidiary of AmerenEnergy  Resources Company, a
wholly-owned  subsidiary  of Ameren,  in  exchange  for a  promissory  note from
Generating  Company in the principal  amount of $552 million and 1,000 shares of
Generating  Company common stock.  The promissory  note has a term of five years
and bears interest at 7 percent based on a 10-year amortization. The transferred
assets represent a generating capacity of approximately 2,900 megawatts.

                                       -5-

<PAGE>

Approximately  45 percent of the  Registrant's  employees  were  transferred  to
Generating Company as a part of the transaction.

Also on May 1, 2000, an electric power supply agreement was entered into between
Generating  Company and a newly  created  nonregulated  affiliate,  AmerenEnergy
Marketing  Company  (Marketing  Company),  also  a  wholly-owned  subsidiary  of
Resources Company. On the same date,  Marketing Company entered into an electric
power supply agreement with the Registrant (Power Supply Agreement) to supply it
sufficient power to meet native load requirements. A portion of the capacity and
energy supplied by Generating Company to Marketing Company will be resold to the
Registrant  for resale to 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.  This agreement  expires December 31, 2004. In turn, the Registrant will
bill these customers at rates which  approximate the costs the Registrant incurs
for its capacity and energy supplied by Generating  Company.  For the five-month
period ended  September  30, 2000,  $157 million of the  Registrant's  purchased
power was derived under the Power Supply Agreement.

As  a  result  of  the  Transfer,  coupled  with  the  Power  Supply  Agreement,
prospectively  from May 1, 2000  through  December 31,  2004,  the  Registrant's
operating   revenues  will  include   revenues   derived  from  its  traditional
transmission and distribution operations,  as well as those revenues it receives
from its native load customers,  or new customers  allowed choice of an electric
supplier  under  state  law.  Sales  under  certain   wholesale   contracts  and
interchange  sales will no longer be  reflected  in  operating  revenues  of the
Registrant.  Instead,  those revenues will be recorded at Resources Company. The
Registrant's  operating expenses will include those expenses it incurs under its
traditional transmission and distribution operations, as well as purchased power
expenses incurred under the terms of the Power Supply Agreement.

In addition,  as a result of the Transfer,  the  Registrant  incurred a deferred
intercompany tax gain,  which resulted in an additional  deferred tax liability.
An intercompany  tax receivable with Generating  Company was established for the
deferred tax  liability.  This asset and liability will be amortized over twenty
years.  At September  30, 2000,  the  Registrant's  deferred tax  liability  and
intercompany tax receivable was $219 million.

MIDWEST ISO

On November 9, 2000, the Registrant announced its intention to withdraw from the
Midwest  Independent  System  Operator  (Midwest  ISO) to become a member of the
Alliance  Regional  Transmission   Organization   (Alliance  RTO),  pending  the
necessary regulatory approvals.  The Alliance RTO, including its rate structure,
is still  subject  to  approval  by the FERC.  Accordingly,  the  Registrant  is
currently unable to determine the impact that the operation of the Alliance RTO,
or the  withdrawal  from the Midwest ISO, will have on its financial  condition,
results of operations or liquidity.


QUANTITATIVE  AND  QUALITATIVE  DISCLOSURES ABOUT MARKET RISK

Market risk  represents the risk of changes in value of a financial  instrument,
derivative or non-derivative,  caused by fluctuations in market variables (e.g.,
interest rates, equity prices, commodity prices, etc.). The following discussion
of  Ameren's,   including  AmerenCIPS',   risk  management  activities  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 also faces risks that are either  non-financial  or
non-quantifiable.  Such risks principally include business,  legal,  operational
and credit risk and are not represented in the following analysis.

Interest Rate Risk
The  Registrant  is exposed to market risk  through  changes in  interest  rates
through its  issuance  of both  long-term  and  short-term  variable-rate  debt,
commercial paper and auction rate preferred  stock.  The Registrant  manages its
interest rate exposure by controlling  the amount of these  instruments it holds
within its total  capitalization  portfolio  and by  monitoring  the  effects of
market changes in interest rates.

If interest rates increase one percentage point in 2001 as compared to 2000, the
Registrant's interest expense would increase by approximately $3 million and net
income  would  decrease  by  approximately  $2  million.  This  amount  has been
determined using the assumptions that the Registrant's outstanding variable rate
debt,  commercial  paper and auction market  preferred stock as of September 30,
2000, continued to be outstanding throughout 2001, and that the average interest
rates for these instruments increased one percentage point over 2000. The model

                                       -6-

<PAGE>

does not consider the effects of the reduced level of 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 its
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 the Registrant's financial structure.

Commodity Price Risk
The  Registrant  is exposed to changes in market prices for natural gas and fuel
and  electricity.   With  regard  to  its  natural  gas  utility  business,  the
Registrant's  exposure to changing  market prices is in large part  mitigated by
the fact that the  Registrant  has a Purchased  Gas  Adjustment  Clause (PGA) in
place.  The PGA allows the  Registrant to pass on to its customers its prudently
incurred costs of natural gas.

While  the  Registrant  does not  have a  provision  similar  to the PGA for its
electric  operations,  purchased power commodity price risk is mitigated in part
due to the fact that the Registrant has entered into a long-term contract with a
supplier for purchased  power (see Electric  Industry  Restructuring  and Note 1
under Notes to Financial Statements for further discussion).  With regard to the
Registrant's  exposure to commodity price risk for purchased  power,  Ameren has
established  a  subsidiary,  AmerenEnergy,  Inc.  (AmerenEnergy),  whose primary
responsibility  includes  managing  market  risks  associated  with the changing
market prices for electricity purchased on behalf of the Registrant.

ACCOUNTING MATTERS

In June 1998, the Financial  Accounting  Standards Board (FASB) issued Statement
of  Financial  Accounting  Standards  (SFAS)  133,  "Accounting  for  Derivative
Instruments  and  Hedging  Activities."  SFAS  133  establishes  accounting  and
reporting  standards for derivative  instruments,  including certain  derivative
instruments embedded in other contracts, and for hedging activities and requires
recognition  of all  derivatives  as either assets or liabilities on the balance
sheet  measured  at fair  value.  In June 1999,  the FASB  issued  SFAS No. 137,
"Accounting for Derivative  Instruments and Hedging Activities - Deferral of the
Effective  Date of FASB  Statement No. 133," which delayed the effective date of
SFAS 133 to all fiscal  quarters of all fiscal years,  beginning  after June 15,
2000.  In June 2000,  the FASB  issued  SFAS No.  138,  "Accounting  for Certain
Derivative  Instruments  and Certain  Hedging  Activities  -an amendment of FASB
Statement No. 133," which amended certain accounting and reporting  standards of
SFAS 133. Management believes that adoption of SFAS 133 will not have a material
impact on the  Registrant's  financial  position or results of  operations  upon
adoption  based on the  derivative  instruments  that  existed at June 30, 2000.
However,  changing market conditions and the volume of future transactions which
fall within the scope of SFAS 133, as amended,  and the interpretations from the
FASB's  Derivative   Implementation  Group  could  change  management's  current
assessment.  As a result, SFAS 133, as amended, could increase the volatility of
the  Registrant's  future  earnings  and could be material  to the  Registrant's
financial position and results of operations upon adoption.

SAFE HARBOR STATEMENT

Statements made in this Form 10-Q 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,
financial  performance  and the Year 2000 Issue.  In  connection  with the "Safe
Harbor" provisions of the Private Securities  Litigation Reform Act of 1995, the
Registrant is providing this cautionary  statement to identify important factors
that could cause actual results to differ materially from those anticipated. The
following factors,  in addition to those discussed  elsewhere in this report and
in the Annual  Report on Form 10-K for the fiscal year ended  December 31, 1999,
and in subsequent  securities filings,  could cause results to differ materially
from management expectations as suggested by such "forward-looking"  statements:
the  effects  of  regulatory  actions;  changes  in laws and other  governmental
actions;  the impact on the  Registrant  of current  regulations  related to the
phasing-in of the  opportunity for some customers to choose  alternative  energy
suppliers in Illinois;  the effects of increased  competition  in the future due
to, among other  things,  deregulation  of certain  aspects of the  Registrant's
business at both the State and Federal levels; future market prices for fuel and
purchased power,  electricity,  and natural gas,  including the use of financial
instruments; average rates for electricity in the Midwest; business and economic
conditions;  interest rates;  weather conditions;  fuel prices and availability;
generation plant performance; the impact of current environmental regulations on
utilities and  generating  companies  and the  expectation  that more  stringent
requirements  will be  introduced  over time,  which  could  potentially  have a
negative  financial  effect;  monetary  and fiscal  policies;  future  wages and
employee benefits costs; and legal and administrative proceedings.



                                       -7-


<PAGE>

<TABLE>
<CAPTION>

                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                                  BALANCE SHEET
                                    UNAUDITED
                      (Thousands of Dollars, Except Shares)


                                                                                             September 30, December 31,
ASSETS                                                                                           2000         1999
<S>                                                                                           <C>          <C>
-------------------------------------------------------------------------------------------   ----------   ----------
Property and plant, at original cost:
   Electric                                                                                   $1,192,443   $2,422,002
   Gas                                                                                           272,661      267,909
                                                                                              ----------   ----------
                                                                                               1,465,104    2,689,911
   Less accumulated depreciation and amortization                                                647,964    1,260,582
                                                                                              ----------   ----------
                                                                                                 817,140    1,429,329
Construction work in progress                                                                      5,986       43,435
                                                                                              ----------   ----------
         Total property and plant, net                                                           823,126    1,472,764
                                                                                              ----------   ----------

Investments and other assets:
   Intercompany notes receivable                                                                 511,701         --
   Intercompany tax receivable                                                                   198,931         --
   Other                                                                                          17,628       17,722
                                                                                              ----------   ----------
         Total investments and other assets                                                      728,260       17,722
                                                                                              ----------   ----------


Current assets:
   Cash and cash equivalents                                                                      20,994       12,536
   Accounts receivable - trade (less allowance for doubtful
         accounts of $2,408 and $1,828, respectively)                                             51,630       48,703
   Unbilled revenue                                                                               77,639       75,884
   Other accounts and notes receivable                                                            41,616       20,875
   Intercompany notes receivable                                                                  39,925         --
   Intercompany tax receivable                                                                    20,065         --
   Materials and supplies, at average cost -
      Fossil fuel                                                                                 24,958       47,291
      Other                                                                                       10,075       33,931
   Other                                                                                           6,418       10,387
                                                                                              ----------   ----------
         Total current assets                                                                    293,320      249,607
                                                                                              ----------   ----------
Regulatory assets:
   Deferred income taxes                                                                             226       21,520
   Other                                                                                          13,742       20,141
                                                                                              ----------   ----------
         Total regulatory assets                                                                  13,968       41,661
                                                                                              ----------   ----------
Total Assets                                                                                  $1,858,674   $1,781,754
                                                                                              ==========   ==========

CAPITAL AND LIABILITIES
Capitalization:
   Common stock, no par value, 45,000,000 shares authorized -
     25,452,373 shares outstanding                                                            $  120,033   $  120,033
   Retained earnings                                                                             434,899      414,345
                                                                                              ----------   ----------
         Total common stockholder's equity                                                       554,932      534,378
   Preferred stock not subject to mandatory redemption                                            80,000       80,000
   Long-term debt                                                                                463,145      493,625
                                                                                              ----------   ----------
        Total capitalization                                                                   1,098,077    1,108,003
                                                                                              ----------   ----------
Current liabilities:
   Current maturity of long-term debt                                                             30,000       35,000
   Intercompany notes payable                                                                    125,720      132,900
   Accounts and wages payable                                                                    167,050       82,800
   Accumulated deferred income taxes                                                              19,627       22,621
   Taxes accrued                                                                                  30,680       32,145
   Other                                                                                          34,003       39,619
                                                                                              ----------   ----------
         Total current liabilities                                                               407,080      345,085
                                                                                              ----------   ----------
Accumulated deferred income taxes                                                                279,937      216,661
Accumulated deferred investment tax credits                                                       13,048       32,169
Regulatory liability                                                                              35,451       34,004
Other deferred credits and liabilities                                                            25,081       45,832
                                                                                              ----------   ----------
Total Capital and Liabilities                                                                 $1,858,674   $1,781,754
                                                                                              ==========   ==========
</TABLE>

See Notes to Financial Statements.

                                       -8-

<PAGE>

<TABLE>
<CAPTION>


                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                               STATEMENT OF INCOME
                                    UNAUDITED
                             (Thousands of Dollars)


                                                 Three Months Ended          Nine Months          Twelve Months Ended
                                                    September 30,             September 30,           September 30,
                                                 2000         1999         2000        1999         2000        1999
                                               ---------    ---------    ---------   ---------    ---------   ---------
<S>                                            <C>          <C>          <C>         <C>          <C>         <C>

 OPERATING REVENUES:
    Electric                                  $ 197,405    $ 261,453    $ 569,239   $ 617,029    $ 747,686   $ 770,081
    Gas                                          21,843       17,874      100,455      91,999      141,102     125,352
                                              ---------    ---------    ---------   ---------    ---------   ---------
 Total operating revenues                       219,248      279,327      669,694     709,028      888,788     895,433

 OPERATING EXPENSES:
    Operations
       Fuel and purchased power                 104,560       82,072      268,318     208,304      374,222     255,246
       Gas                                       10,081        7,324       54,241      50,326       77,267      66,304
       Other                                     26,505       54,944       97,951     140,923      147,650     186,308
                                              ---------    ---------    ---------   ---------    ---------   ---------
                                                141,146      144,340      420,510     399,553      599,139     507,858
    Maintenance                                   7,494       24,741       35,547      67,309       71,820      88,698
    Depreciation and amortization                12,221       20,141       48,807      60,330       69,034      79,862
    Income taxes                                 21,044       26,204       47,165      43,380       34,558      49,036
    Other taxes                                   6,349       10,056       28,752      29,921       39,144      42,184
                                              ---------    ---------    ---------   ---------    ---------   ---------
       Total operating expenses                 188,254      225,482      580,781     600,493      813,695     767,638

 OPERATING INCOME                                30,994       53,845       88,913     108,535       75,093     127,795

 OTHER INCOME AND (DEDUCTIONS):
    Allowance for equity funds used
       during construction                         --             (9)        --            (8)        --           (37)
    Miscellaneous, net                           10,172          533       17,988       1,614       18,404       1,204
                                              ---------    ---------    ---------   ---------    ---------   ---------
        Total other income and (deductions)      10,172          524       17,988       1,606       18,404       1,167

 INCOME BEFORE
    INTEREST CHARGES                             41,166       54,369      106,901     110,141       93,497     128,962

 INTEREST CHARGES:
    Interest                                      9,391       10,748       28,738      31,906       39,568      41,819
    Allowance for borrowed funds
       used during construction                     (53)         338           99         (43)         163        (143)
                                              ---------    ---------    ---------   ---------    ---------   ---------
    Net interest charges                          9,338       11,086       28,837      31,863       39,731      41,676

NET INCOME                                       31,828       43,283       78,064      78,278       53,766      87,286

PREFERRED STOCK DIVIDENDS                         1,027          957        2,857       2,842        3,848       3,786
                                              ---------    ---------    ---------   ---------    ---------   ---------

NET INCOME AFTER PREFERRED
   STOCK DIVIDENDS                            $  30,801    $  42,326    $  75,207   $  75,436    $  49,918   $  83,500
                                              =========    =========    =========   =========    =========   =========

</TABLE>

See Notes to Financial Statements.

                                       -9-

<PAGE>

<TABLE>
<CAPTION>

                     CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
                             STATEMENT OF CASH FLOWS
                                    UNAUDITED
                             (Thousands of Dollars)




                                                                                       Nine  Months Ended
                                                                                         September 30,
                                                                                       2000         1999

<S>                                                                                 <C>          <C>
                                                                                    ---------    ---------
Cash Flows From Operating:
   Net income                                                                       $  78,064    $  78,278
   Adjustments to reconcile net income to net cash
      provided by operating activities:
        Depreciation and amortization                                                  48,807       60,330
        Allowance for funds used during construction                                       99          (35)
        Deferred income taxes, net                                                      9,503      (12,774)
        Deferred investment tax credits, net                                              607       (1,863)
        Changes in assets and liabilities:
           Receivables, net                                                           (25,423)     (42,285)
           Materials and supplies                                                      (7,617)       5,367
           Accounts and wages payable                                                  84,403       27,134
           Taxes accrued                                                               (1,465)      13,598
           Other, net                                                                 (47,711)      35,741
                                                                                    ---------    ---------
Net cash provided by operating activities                                             139,267      163,491

Cash Flows From Investing:
   Construction expenditures                                                          (30,602)     (80,601)
   Allowance for funds used during construction                                           (99)          35
                                                                                    ---------    ---------
Net cash used in investing activities                                                 (30,701)     (80,566)

Cash Flows From Financing:
   Dividends on common stock                                                          (54,171)     (53,297)
   Dividends on preferred stock                                                        (2,857)      (2,957)
   Redemptions -
      Short-term debt                                                                    --        (46,700)
      Long-term debt                                                                  (87,000)     (60,000)
      Intercompany notes payable                                                       (7,180)        --
   Issuances -
      Long-term debt                                                                   51,100         --
      Intercompany notes payable                                                         --         91,200
                                                                                    ---------    ---------
Net cash used in financing activities                                                (100,108)     (71,754)
                                                                                    ---------    ---------

Net change in cash and cash equivalents                                                 8,458       11,171
Cash and cash equivalents at beginning of year                                         12,536       10,180
                                                                                    ---------    ---------
Cash and cash equivalents at end of period                                          $  20,994    $  21,351
                                                                                    =========    =========

Cash paid during the periods:
   Interest (net of amount capitalized)                                             $  30,619    $  28,990
   Income taxes, net                                                                $  34,509    $  39,983

</TABLE>


SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTION:
In  the  second  quarter  of  2000,  the  Registrant  transferred  its  electric
generating  assets and  liabilities,  at historical  net book value,  to a newly
created nonregulated company,  AmerenEnergy  Generating Company, a subsidiary of
AmerenEnergy   Resources  Company,  in  exchange  for  a  promissory  note  from
Generating  Company  in the  principal  amount of $552  million  and  Generating
Company common stock. The transaction  also resulted in a deferred  intercompany
tax gain  liability  and related tax  receivable  from  AmerenEnergy  Generating
Company  in the  amount  of $219  million.  See  Note 1 in  Notes  to  Financial
Statements for further information.

See Notes to Financial Statements.

                                      -10-

<PAGE>

CENTRAL ILLINOIS PUBLIC SERVICE COMPANY
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
September 30, 2000


Note 1 - Central Illinois Public Service Company  (AmerenCIPS or the Registrant)
is a subsidiary of Ameren Corporation  (Ameren),  which is the parent company of
the following  operating  companies:  the  Registrant,  Union  Electric  Company
(AmerenUE)  and  AmerenEnergy   Generating  Company  (Generating   Company),   a
wholly-owned  subsidiary of AmerenEnergy  Resources Company (Resources Company).
Ameren is a registered  holding company under the Public Utility Holding Company
Act of  1935  (PUHCA)  formed  in  December  1997  upon  the  merger  of  CIPSCO
Incorporated  (the Registrant's  former parent) and AmerenUE (the Merger).  Both
Ameren and its  subsidiaries  are subject to the  regulatory  provisions  of the
PUHCA.  The  operating  companies  are engaged  principally  in the  generation,
transmission,  distribution  and  sale of  electric  energy  and  the  purchase,
distribution,  transportation  and sale of natural gas in the states of Illinois
and  Missouri.  Contracts  among the  companies--dealing  with  jointly-operated
generating facilities,  interconnecting  transmission lines, and the exchange of
electric power--are regulated by the Federal Energy Regulatory Commission (FERC)
or the Securities and Exchange Commission (SEC). Administrative support services
are provided to the Registrant by a separate Ameren subsidiary,  Ameren Services
Company.  The Registrant  serves 400,000 electric and 175,000 gas customers in a
20,000 square-mile region of central and southern Illinois.

The Registrant also has a 20 percent  interest in Electric  Energy,  Inc. (EEI),
which is  accounted  for under the  equity  method of  accounting.  EEI owns and
operates electric generating and transmission facilities in Illinois that supply
electric  power  primarily  to a uranium  enrichment  plant  located in Paducah,
Kentucky.

In  conjunction  with the Illinois  Electric  Service  Customer  Choice and Rate
Relief Law of 1997, on May 1, 2000,  following the receipt of all required State
and Federal  regulatory  approvals,  the  Registrant  transferred  its  electric
generating  assets and  liabilities,  at historical  net book value,  to a newly
created  nonregulated  company,  Generating Company,  for a promissory note from
Generating  Company in the principal  amount of $552 million and 1,000 shares of
Generating  Company common stock (the Transfer).  The promissory note has a term
of five years and bears  interest at 7 percent based on a 10-year  amortization.
The transferred  assets represent a generating  capacity of approximately  2,900
megawatts.   Approximately  45  percent  of  the  Registrant's   employees  were
transferred to Generating Company as a part of the transaction.  The significant
components of the net assets transferred are as follows:

(Thousands of dollars)
Cash                                               $       6,387
Other receivable - intercompany                           26,000
Material and supplies                                     53,806
Other current assets                                       5,522
Property and plant, net                                  635,031
                                                  ---------------

Total assets transferred                          $      726,746
                                                  ---------------


Accounts payable                                   $       6,541
Other current liabilities                                  3,351
Other deferred credits                                     1,804
Deferred investment tax credits                           19,728
Deferred tax liabilities, net                            143,696
                                                  ---------------

Total liabilities transferred                     $      175,120
                                                  ---------------


Net assets transferred                            $      551,626
                                                  ---------------

Also on May 1, 2000, an electric power supply agreement was entered into between
Generating  Company and a newly  created  nonregulated  affiliate,  AmerenEnergy
Marketing  Company  (Marketing  Company),  also  a  wholly-owned  subsidiary  of
Resources Company. On the same date,  Marketing Company entered into an electric
power supply agreement with the Registrant (Power Supply Agreement) to supply it
sufficient power to meet native load

                                      -11-

<PAGE>

requirements.  A portion of the  capacity  and  energy  supplied  by  Generating
Company to  Marketing  Company  will be resold to the  Registrant  for resale to
native load  customers at rates  specified by the Illinois  Commerce  Commission
(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.  This  agreement  expires  December 31, 2004. In turn,  the
Registrant  will bill these  customers at rates which  approximate the costs the
Registrant  incurs for its capacity and energy  supplied by Generating  Company.
For the  five-month  period  ended  September  30,  2000,  $157  million  of the
Registrant's purchased power was derived under the Power Supply Agreement.

As a result of the Transfer, coupled with the Power Supply Agreement between the
Registrant  and  Marketing  Company,  prospectively  from  May 1,  2000  through
December 31, 2004, the  Registrant's  operating  revenues will include  revenues
derived from its traditional transmission and distribution  operations,  as well
as those revenues it receives from its native load  customers,  or new customers
allowed  choice of an electric  supplier  under state law.  Sales under  certain
wholesale  contracts  and  interchange  sales  will no  longer be  reflected  in
operating revenues of the Registrant.  Instead,  those revenues will be recorded
at Resources  Company.  The Registrant's  operating  expenses will include those
expenses  it  incurs  under  its  traditional   transmission   and  distribution
operations,  as well as purchased power expenses incurred under the terms of the
Power Supply Agreement.

In addition, as a result of the transaction,  the Registrant incurred a deferred
intercompany tax gain,  which resulted in an additional  deferred tax liability.
An intercompany  tax receivable with Generating  Company was established for the
deferred tax  liability.  This asset and liability will be amortized over twenty
years.  At September  30, 2000,  the  Registrant's  deferred tax  liability  and
intercompany tax receivable was $219 million.

Note 2 - Financial  statement note  disclosures,  normally included in financial
statements prepared in conformity with generally accepted accounting principles,
have been omitted in this Form 10-Q pursuant to the Rules and Regulations of the
SEC.  However,  in the opinion of the Registrant,  the disclosures  contained in
this Form 10-Q are adequate to make the  information  presented not  misleading.
See Notes to Financial Statements included in the 1999 Form 10-K for information
relevant to the  financial  statements  contained  in this Form 10-Q,  including
information as to the significant accounting policies of the Registrant.

Note 3 - In the  opinion of the  Registrant,  the interim  financial  statements
filed as part of this Form 10-Q  reflect  all  adjustments,  consisting  only of
normal recurring adjustments,  necessary for a fair statement of the results for
the periods presented.  The Registrant's  financial  statements were prepared to
permit the information  required in the Financial Data Schedule  (FDS),  Exhibit
27,  to be  directly  extracted  from  the  filed  statements.  The FDS  amounts
correspond  to or are  calculable  from the amounts  reported  in the  financial
statements or notes thereto.

Note 4 - Due to the  effect of  weather  on sales and  other  factors  which are
characteristic of public utility  operations,  financial results for the periods
ended September 30, 2000 and 1999, are not necessarily  indicative of trends for
any three-month, nine-month or 12-month period.

Note 5 - The Registrant has  transactions  in the normal course of business with
other Ameren  subsidiaries.  These transactions are primarily comprised of power
purchases and sales and services received or rendered.  Intercompany receivables
included in other accounts and notes receivable were  approximately  $26 million
and $12 million,  respectively,  as of September 30, 2000 and December 31, 1999.
Intercompany   payables   included  in  accounts  and  wages   payable   totaled
approximately $108 and $35 million,  respectively,  as of September 30, 2000 and
December 31, 1999.

In addition,  the Registrant has the ability to borrow up to approximately  $950
million from Ameren or AmerenUE or invest funds  through a regulated  money pool
agreement.  The regulated  money pool was  established to coordinate and provide
for certain short-term cash and working capital requirements and is administered
by Ameren Services Company.  Interest is calculated at varying rates of interest
depending on the  composition  of internal and external  funds in the  regulated
money  pool.  At  September  30,  2000,  the  Registrant  had  $126  million  of
intercompany  borrowings  outstanding  and $484  million  available  through the
regulated money pool.

Note 6 - On November 9, 2000, the Registrant announced its intention to withdraw
from the Midwest Independent System Operator (Midwest ISO) to become a member of
the Alliance  Regional  Transmission  Organization  (Alliance RTO),  pending the
necessary regulatory approvals.  The Alliance RTO, including its rate structure,
is still  subject  to  approval  by the FERC.  Accordingly,  the  Registrant  is
currently unable to determine the impact that the operation of the Alliance RTO,
or the  withdrawal  from the Midwest ISO, will have on its financial  condition,
results of operations or liquidity.

                                      -12-

<PAGE>

Note 7 - In September 2000, the Registrant and its affiliate,  AmerenUE, filed a
request with the Illinois  Commerce  Commission  (ICC) seeking  authorization to
transfer  AmerenUE's  Illinois-based  electric  and natural gas business and its
Illinois-based  distribution  and  transmission  assets  and  personnel  to  the
Registrant.  The distribution and  transmission  assets and related  liabilities
will be transferred from AmerenUE to the Registrant at historical net book value
of  approximately  $100  million.  In  connection  with  this  transaction,  the
Registrant will issue an intercompany  note payable to AmerenUE of approximately
$50 million.  The balance of the assets will be transferred to the Registrant in
the form of a capital  contribution.  In October 2000,  AmerenUE filed a request
with the Missouri  Public Service  Commission for approval of the transfer.  The
transfer is also subject to regulatory  filings and  approvals of the FERC,  the
SEC and the ICC.

Note 8 -  Segment  information  for the  three-month,  nine-month  and  12-month
periods ended September 30, 2000 and 1999 is as follows:

--------------------------------------------------------------------------------

(in thousands)                              Electric        Gas         Total
--------------------------------------------------------------------------------

Three months ended September 30, 2000:

Revenues                                  $197,405        $21,843     $219,248
Operating Income (Net)                      27,175          3,819       30,994
--------------------------------------------------------------------------------

Three months ended September 30, 1999:

Revenues                                  $261,453        $17,874     $279,327
Operating Income (Net)                      53,763             82       53,845
--------------------------------------------------------------------------------

Nine months ended September 30, 2000:

Revenues                                  $569,239       $100,455     $669,694
Operating Income (Net)                      77,615         11,298       88,913
--------------------------------------------------------------------------------

Nine months ended September 30, 1999:

Revenues                                  $617,029        $91,999     $709,028
Operating Income (Net)                     102,182          6,353      108,535
--------------------------------------------------------------------------------

12 months ended September 30, 2000:

Revenues                                  $747,686        $141,102    $888,788
Operating Income (Net)                      61,120          13,973      75,093
--------------------------------------------------------------------------------

12 months ended September 30, 1999:

Revenues                                  $770,081        $125,352    $895,433
Operating Income (Net)                     119,358           8,437     127,795
--------------------------------------------------------------------------------


                                      -13-

<PAGE>


                           PART II. OTHER INFORMATION


ITEM 1. LEGAL PROCEEDINGS
        -----------------

Reference  is  made  to  "Regulation"   section  in  Item  1.  Business  of  the
Registrant's  Form 10-K for the year ended  December  31, 1999 and Item 1. Legal
Proceedings in Part II of the  Registrant's  Form 10-Q for the quarterly  period
ended June 30, 2000,  for  information  relating to  litigation  concerning  the
alleged  exposure  to  carcinogens  contained  in coal  tar at the  Registrant's
Taylorville,  Illinois  manufactured  gas plant  site.  On October 4, 2000,  the
Illinois  Supreme  Court granted the  Registrant's  request to review a decision
issued by the Illinois Appellate Court in March 2000 which upheld a $3.2 million
verdict  in favor of the  plaintiffs  against  the  Registrant.  The  Registrant
believes that final  disposition of this matter will not have a material adverse
effect on its financial position, results of operations or liquidity.

On August 24, 2000,  Steven and Tina Brannon  sued the  Registrant,  its parent,
Ameren Corporation,  and its affiliate,  AmerenEnergy Generating Company in the
Circuit  Court  of  Christian  County,  Illinois.  The  suit  alleges  that  the
Registrant  and others were  negligent  in the manner in which the  Registrant's
manufactured gas plant site was  remediated in Taylorville, Illinois, therefore,
wrongfully  causing the death of their son. The  Brannon's son was born in 1992,
diagnosed with neuroblastoma in 1996, and died in 1998. The remediation occurred
in 1987. Plaintiffs seek unspecified  compensatory damages in excess of $50,000.
The Registrant  believes that the final resolution of this lawsuit will not have
a material  adverse effect on its financial  position,  results of operations or
liquidity.

Reference is made to Item 1. Legal  Proceedings  in Part II of the  Registrant's
Form 10-Q for the quarterly period ended June 30, 2000, for information relating
to a  lawsuit  filed  in the  Circuit  Court of  Madison  County,  Illinois,  by
twenty-three  named plaintiffs  alleging  negligence on behalf of the Registrant
and Dover  Elevator  Company  (Dover)  for  injuries  arising out of an elevator
accident which occurred at the Registrant's Newton Power Plant in November 1996.
In  mid-October  2000, a settlement  agreement was entered into which (i) capped
all of the plaintiffs' damages and (ii) apportioned fault between the Registrant
and Dover as to approximately one-half of the plaintiffs.  The settlement amount
is the subject of a confidentiality  agreement.  Subsequently,  an apportionment
trial was held between the Registrant and Dover as to the remaining  plaintiffs.
The jury  found the  Registrant  ninety-five  percent  at fault  and Dover  five
percent at fault. The Registrant has adequate  insurance to cover the settlement
and the judgment entered in these proceedings.  As such, the final resolution of
this  lawsuit  will not  have a  material  adverse  effect  on the  Registrant's
financial position, results of operations or liquidity.


ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K
         --------------------------------

         (a)   Exhibits.

               Exhibit 12 -  Computation  of Ratio of Earnings to Fixed  Charges
               and  Preferred  Stock  Dividend  Requirements,  12  Months  Ended
               September 30, 2000.

               Exhibit 27 - Financial Data Schedule.

         (b)   Reports on Form 8-K.  None.

                                      -14-

<PAGE>





                                   SIGNATURES

     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/ Warner L. Baxter
                                                  -----------------------
                                              Vice President and Controller
                                              (Principal Accounting Officer)


Date:  November 14, 2000

                                      -15-