<PAGE>
                                  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 June 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 1-2967.

                             UNION ELECTRIC COMPANY
             (Exact name of registrant as specified in its charter)

           Missouri                                              43-0559760
(State or other jurisdiction of                               (I.R.S. Employer
incorporation or organization)                               Identification No.)


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


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


    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 July
  31, 2000:  Common  Stock,  $5 par value,  held by Ameren  Corporation  (parent
  company of Registrant) - 102,123,834


<PAGE>



                             Union Electric Company

                                      Index

                                                                       Page No.

Part I               Financial Information (Unaudited)

                     Management's Discussion and Analysis                  2

                     Quantitative and Qualitative Disclosures
                     About Market Risk                                     5

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

                     Statement of Income
                     - Three months, six months and 12 months ended
                        June 30, 2000 and 1999                             9

                     Statement of Cash Flows
                     - Six months ended June 30, 2000 and 1999            10

                     Notes to Financial Statements                        11


Part II              Other Information                                    14


<PAGE>

                    PART I. FINANCIAL INFORMATION (UNAUDITED)

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

OVERVIEW

Union Electric  Company  (AmerenUE 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,  AmerenUE  and CIPSCO
Incorporated  (CIPSCO)  combined to form  Ameren,  with  AmerenUE  and  CIPSCO's
subsidiaries,  Central  Illinois Public Service Company  (AmerenCIPS) and CIPSCO
Investment Company (CIC), becoming subsidiaries of Ameren (the Merger).

The following  discussion and analysis  should be read in  conjunction  with the
Notes to the  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 the  Financial  Statements
appearing in the Registrant's 1999 Form 10-K.


RESULTS OF OPERATIONS

Earnings
Second  quarter 2000 earnings of $85 million  increased $17 million  compared to
1999 second quarter  earnings.  Earnings for the six months ended June 30, 2000,
increased $12 million from the year ago period to $122 million. Earnings for the
12 months ended June 30, 2000 were $352 million, a $23 million increase from the
preceding  12-month  period.   Earnings   fluctuated  due  to  many  conditions,
primarily:  weather  variations,  credits to electric  customers,  electric rate
reductions,  gas  rate  increases,  competitive  market  forces,  sales  growth,
fluctuating   operating  costs  (including   Callaway  Nuclear  Plant  refueling
outages), changes in interest expense, changes in income and property taxes, and
a nonrecurring charge for a targeted employee separation plan.

The  significant  items  affecting  revenues,  costs  and  earnings  during  the
three-month,  six-month  and 12-month  periods  ended June 30, 2000 and 1999 are
detailed on the following pages.

Electric Operations
Electric Operating Revenues        Variations for periods ended June  30, 2000
                                       from comparable prior-year periods
--------------------------------------------------------------------------------
(Millions of Dollars)           Three Months      Six Months      Twelve Months
                                ------------      ----------      -------------
--------------------------------------------------------------------------------
Rate variations                   $   -             $   -            $   2
Credit to customers                  (5)                5              (11)
Effect of abnormal weather           (6)              (16)             (33)
Growth and other                     39                42               91
Interchange sales                    28                83              151
--------------------------------------------------------------------------------
                                  $  56             $ 114            $ 200
--------------------------------------------------------------------------------

The $56 million  increase in second quarter  electric  revenues  compared to the
year-ago  quarter was primarily  driven by a 30 percent  increase in interchange
sales due to strong marketing  efforts.  In addition,  revenues increased due to
increased residential,  commercial and industrial sales, by 2 percent, 8 percent
and 2  percent,  respectively,  offset in part by lower  wholesale  sales and an
increase in the  estimated  credit to Missouri  electric  customers  (see Note 5
under Notes to Financial Statements for further information).

Electric  revenues  for the first  six  months of 2000  increased  $114  million
compared to the same 1999 period.  The increase in revenues was primarily due to
a 60 percent increase in interchange sales due to strong marketing efforts and a
decrease in the  estimated  credit to Missouri  electric  customers  (see Note 5
under Notes to  Financial  Statements  for further  information).  In  addition,
revenues  increased  due to increased  residential,  commercial  and  industrial
sales, by 2 percent, 6 percent and 1 percent, respectively.

                                      -2-
<PAGE>

Electric  revenues for the 12 months ended June 30, 2000 and 1999 increased $200
million  compared to the prior  12-month  period.  The  increase in revenues was
primarily due to a 35 percent  increase in interchange  sales,  coupled with a 3
percent increase in commercial sales.

Fuel and Purchased Power          Variations for periods ended June  30, 2000
                                       from comparable prior-year periods
--------------------------------------------------------------------------------
(Millions of Dollars)           Three Months      Six Months      Twelve Months
                                ------------      ----------      -------------
--------------------------------------------------------------------------------
Fuel:
 Generation                       $   2             $  7              $ (7)
 Price                               (5)              (8)                1
 Generation efficiencies and other   (2)              (5)               (8)
Purchased power variation            15               68               160
--------------------------------------------------------------------------------
                                  $  10             $ 62              $146
--------------------------------------------------------------------------------


The increase in fuel and  purchased  power costs for the three month,  six month
and 12 month  periods ended June 30, 2000,  compared to the year ago  comparable
periods,  was primarily due to increased  purchased  power resulting from higher
sales volumes.

Gas Operations
Gas revenues for the quarter ended June 30, 2000  increased $5 million  compared
to the  prior-year  period  primarily  due to a 37 percent  increase in sales to
ultimate consumers.

Gas costs for the 12 months ended June 30, 2000 increased $5 million compared to
the year-ago period, primarily due to higher gas prices.

Other Operating Expenses
Other operating expense variations  reflected  recurring factors such as growth,
inflation, labor and benefit increases.

Other  operations  expenses  for the three and six months  ended  June 30,  2000
increased  $5  million  and $12  million,  respectively,  compared  to the  same
year-ago periods  primarily due to increased costs associated with the automated
meter reading roll-out and  professional  services.  Other  operations  expenses
decreased $8 million for the 12 months ended June 30, 2000, compared to the same
year-ago period  primarily due to the 1998 one-time pretax charge of $18 million
for a targeted separation plan.

Maintenance  expenses  for the  three,  six and 12 months  ended  June 30,  2000
increased $13 million,  $14 million and $36 million,  respectively,  compared to
the year-ago periods primarily due to increased power plant maintenance and tree
trimming activity.

Taxes
Income taxes increased $11 million,  $9 million and $11 million,  for the three,
six and 12 months  ended  June 30,  2000,  respectively,  due to  higher  pretax
income.

Other tax expense decreased $8 million for the 12 months ended June 30, 2000 due
primarily  to a decrease in gross  receipts  taxes  related to the  Registrant's
Illinois  jurisdiction.  This decrease is the result of the restructuring of the
Illinois  public utility tax whereby gross receipts taxes are no longer recorded
as electric revenues and gross receipts tax expense.

Balance Sheet

The $58 million  increase in trade accounts  receivable and unbilled  revenue at
June 30, 2000, compared to the year-end, was due primarily to higher revenues in
May and June 2000 compared to November and December 1999.

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

                                      -3-

<PAGE>

LIQUIDITY AND CAPITAL RESOURCES

Cash  provided by operating  activities  totaled $161 million for the six months
ended June 30, 2000, compared to $266 million during the same 1999 period.

Cash flows used in  investing  activities  totaled $171 million and $277 million
for the six months  ended  June 30,  2000 and 1999,  respectively.  Construction
expenditures  for the six months ended June 30, 2000,  for  constructing  new or
improving  existing  facilities were $166 million.  In addition,  the Registrant
expended $8 million for the acquisition of nuclear fuel. The Registrant received
Board of  Directors  approval  on April  25,  2000 to spend  approximately  $160
million  on  capital  expenditures  relating  to the  replacement  of four steam
generators  at its  Callaway  Nuclear  Plant.  Installation  is  scheduled to be
completed in 2005. The impact on anticipated 2000 capital  expenditures  will be
insignificant.

Cash flows used in financing  activities totaled $106 million for the six months
ended June 30, 2000,  compared to $23 million  during the same 1999 period.  The
Registrant's principal financing activities for the period included the issuance
and redemption of long-term debt and the payment of dividends.

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  under  PUHCA to have up to $1  billion 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 June 30,
2000, the Registrant had committed bank lines of credit aggregating $150 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 June 30, 2000, the Registrant
had no outstanding short-term borrowings.

The  Registrant  also has a bank  credit  agreement  due 2002 which  permits the
borrowing of up to $300 million on a long-term  basis,  all of which was unused,
and $113 was available at June 30, 2000.  In addition,  the  Registrant  has the
ability to borrow up to  approximately  $525 million  from Ameren or  AmerenCIPS
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.  As of June 30,  2000,  $196  million  was  available  through  the
regulated money pool.

Additionally,  the  Registrant  has a  lease  agreement  that  provides  for the
financing of nuclear  fuel. At June 30, 2000,  the maximum  amount that could be
financed under the agreement was $120 million. Cash used in financing activities
for the six months ended June 30, 2000, included redemptions under the lease for
nuclear fuel of $4 million, offset by $6 million of issuances. At June 30, 2000,
$119 million was financed under the lease.

The Registrant,  in the ordinary course of business,  explores  opportunities to
reduce its costs in order to remain competitive in the marketplace.  Areas where
the Registrant  focuses its review include,  but are not limited to, labor costs
and fuel supply costs. In the labor area, the Registrant has reached  agreements
with some of the Registrant's  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.  In the fuel supply area, the Registrant
explores  alternatives  to  effectively  manage its overall  fuel  costs.  These
alternatives  include  diversifying  fuel  sources  for use at the  Registrant's
fossil plants, as well as restructuring or terminating  existing  contracts with
suppliers.

Certain  of  these  cost  reduction  alternatives  could  result  in  additional
investments  being  made at the  Registrant's  power  plants in order to utilize
different  types of coal,  or could  require  nonrecurring  payments of employee
separation  benefits or  nonrecurring  payments to  restructure  or terminate an
existing fuel  contract  with a supplier.  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.

                                      -4-

<PAGE>

RATE MATTERS

In February  2000,  the  Registrant  filed a request  with the  Missouri  Public
Service Commission (MoPSC) to increase rates  approximately $12 million annually
for  natural  gas  service  in the  Missouri  jurisdiction.  The MoPSC has until
January 2001 to render a decision.

See Note 5 under Notes to Financial  Statements  for further  discussion of Rate
Matters.


ELECTRIC INDUSTRY RESTRUCTURING

Certain states are considering  proposals or have adopted  legislation that will
promote  competition  at the retail  level.  In December  1997,  the Governor of
Illinois signed the Electric Service Customer Choice and Rate Relief Law of 1997
(the Illinois Law)  providing for electric  utility  restructuring  in Illinois.
This  legislation  introduces  competition into the supply of electric energy in
Illinois.

The Illinois Law, among other things,  requires 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  6 percent of the
Registrant's  total  sales.  As of June 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.


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 interest  rates and
equity prices.  The following  discussion of the  Registrant's  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.  The  Registrant  handles  market  risks  in
accordance with  established  policies,  which may include entering into various
derivative  transactions.  In the normal course of business, the Registrant 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 and
commercial  paper.  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 $7 million and net
income  would  decrease  by  approximately  $4  million.  This  amount  has been
determined using the assumptions that the Registrant's outstanding variable rate
debt as of June 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 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 Registrant has Purchased Gas Adjustment  Clauses (PGA) in place in
both its Missouri and Illinois  jurisdictions.  The PGA allows the Registrant to
pass on to its customers its prudently incurred costs of natural gas.

                                      -5-

<PAGE>

Since  the  Registrant  does not  have a  provision  similar  to the PGA for its
electric operations, the Registrant has entered into several long-term contracts
with various  suppliers to purchase coal and nuclear fuel to manage its exposure
to fuel prices. With regard to the Registrant's exposure to commodity price risk
for  purchased  power and excess  electricity  sales,  Ameren has  established a
subsidiary,  AmerenEnergy,  Inc.,  (AmerenEnergy)  whose primary  responsibility
includes  managing  market risks  associated with the changing market prices for
electricity purchased and sold on behalf of the Registrant.

AmerenEnergy  utilizes  several  techniques  to  mitigate  its  market  risk for
electricity,  including utilizing derivative financial instruments. A derivative
is a contract  whose  value is  dependent  on or derived  from the value of some
underlying  asset. The derivative  financial  instruments  that  AmerenEnergy is
allowed to utilize (which include  forward  contracts,  futures  contracts,  and
option  contracts)  are  dictated by a risk  management  policy,  which has been
reviewed with the Auditing Committee of Ameren's Board of Directors.  Compliance
with the risk  management  policy  is the  responsibility  of a risk  management
steering  committee,  consisting  of Ameren  officers  and an  independent  risk
management officer at AmerenEnergy.

As of June 30, 2000, the fair value of derivative financial  instruments exposed
to commodity price risk was immaterial.

Equity Price Risk

The  Registrant  maintains  trust funds,  as required by the Nuclear  Regulatory
Commission  and  Missouri  and Illinois  state laws,  to fund  certain  costs of
nuclear  decommissioning.  As of  June  30,  2000,  these  funds  were  invested
primarily in domestic equity securities,  fixed-rate,  fixed-income  securities,
and cash  and  cash  equivalents.  By  maintaining  a  portfolio  that  includes
long-term equity investments,  the Registrant is seeking to maximize the returns
to be  utilized  to fund  nuclear  decommissioning  costs.  However,  the equity
securities  included  in  the  Registrant's   portfolio  are  exposed  to  price
fluctuations in equity markets, and the fixed-rate,  fixed-income securities are
exposed to changes in interest  rates.  The  Registrant  actively  monitors  its
portfolio by benchmarking  the  performance of its  investments  against certain
indices and by  maintaining,  and  periodically  reviewing,  established  target
allocation  percentages  of the  assets  of its  trusts  to  various  investment
options. The Registrant's  exposure to equity price market risk is in large part
mitigated due to the fact that the  Registrant  is currently  allowed to recover
its decommissioning costs in its rates.


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

                                      -6-

<PAGE>

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>

                             UNION ELECTRIC COMPANY
                                  BALANCE SHEET
                                    UNAUDITED
                      (Thousands of Dollars, Except Shares)


                                                                   June 30,   December 31,
ASSETS                                                              2000         1999
------                                                           ----------   ------------
<S>                                                             <C>          <C>

Property and plant, at original cost:
   Electric                                                      $9,331,165   $9,210,122
   Gas                                                              230,897      223,789
   Other                                                             37,156       37,156
                                                                 ----------   ----------
                                                                  9,599,218    9,471,067
   Less accumulated depreciation and amortization                 4,445,047    4,320,910
                                                                 ----------   ----------
                                                                  5,154,171    5,150,157
Construction work in progress:
   Nuclear fuel in process                                           97,635       88,830
   Other                                                            108,360       92,833
                                                                 ----------   ----------
         Total property and plant, net                            5,360,166    5,331,820
                                                                 ----------   ----------
Investments and other assets:
   Nuclear decommissioning trust fund                               191,687      186,760
   Other                                                             61,396       59,748
                                                                 ----------   ----------
         Total investments and other assets                         253,083      246,508
                                                                 ----------   ----------
Current assets:
   Cash and cash equivalents                                          1,602      117,308
   Accounts receivable - trade (less allowance for doubtful
         accounts of $7,872 and $5,308, respectively)               176,017      151,399
   Unbilled revenue                                                 111,788       78,213
   Other accounts and notes receivable                               51,545       19,803
   Intercompany notes receivable                                    169,120      165,700
   Materials and supplies, at average cost -
      Fossil fuel                                                    61,154       65,292
      Other                                                          79,597       90,921
   Other                                                             19,639       19,205
                                                                 ----------   ----------
         Total current assets                                       670,462      707,841
                                                                 ----------   ----------
Regulatory assets:
   Deferred income taxes                                            600,343      600,604
   Other                                                            153,105      156,789
                                                                 ----------   ----------
         Total regulatory assets                                    753,448      757,393
                                                                 ----------   ----------
Total Assets                                                     $7,037,159   $7,043,562
                                                                 ==========   ==========

CAPITAL AND LIABILITIES
Capitalization:
   Common stock, $5 par value, 150,000,000 shares authorized -
     102,123,834 shares outstanding                              $  510,619   $  510,619
   Other paid-in capital, principally premium on
     common stock                                                   701,896      701,896
   Retained earnings                                              1,204,696    1,221,167
                                                                 ----------   ----------
         Total common stockholder's equity                        2,417,211    2,433,682
   Preferred stock not subject to mandatory redemption              155,197      155,197
   Long-term debt                                                 1,919,662    1,882,601
                                                                 ----------   ----------
         Total capitalization                                     4,492,070    4,471,480
                                                                 ----------   ----------
Current liabilities:
   Current maturity of long-term debt                                12,782       11,423
   Accounts and wages payable                                       188,721      234,845
   Accumulated deferred income taxes                                 45,607       48,139
   Taxes accrued                                                    179,355      119,699
   Other                                                            165,217      208,373
                                                                 ----------   ----------
         Total current liabilities                                  591,682      622,479
                                                                 ----------   ----------
Accumulated deferred income taxes                                 1,260,723    1,248,721
Accumulated deferred investment tax credits                         135,740      138,665
Regulatory liability                                                151,578      154,399
Other deferred credits and liabilities                              405,366      407,818
                                                                 ----------   ----------
Total Capital and Liabilities                                    $7,037,159   $7,043,562
                                                                 ==========   ==========

</TABLE>

See Notes to Financial Statements.

                                      -8-

<PAGE>

<TABLE>
<CAPTION>

                             UNION ELECTRIC COMPANY
                               STATEMENT OF INCOME
                                    UNAUDITED
                             (Thousands of Dollars)




                                                  Three Months Ended            Six Months Ended             Twelve MonthsEnded
                                                     June 30,                       June 30,                        June 30,
                                                 ---------------------        ---------------------         ----------------------
                                                  2000           1999          2000           1999           2000           1999
                                                  ----           ----          ----           ----           ----           ----

<S>                                          <C>            <C>            <C>            <C>            <C>            <C>
 OPERATING REVENUES:
    Electric                                 $   664,197    $   608,429    $ 1,183,310    $ 1,069,563    $ 2,548,764    $ 2,348,810
    Gas                                           18,095         12,787         60,172         57,704         94,446         93,164
    Other                                           --              151           --              171           --              274
                                             -----------    -----------    -----------    -----------    -----------    ------------
       Total operating revenues                  682,292        621,367      1,243,482      1,127,438      2,643,210      2,442,248

 OPERATING EXPENSES:
    Operations
       Fuel and purchased power                  179,176        168,842        351,614        289,417        718,731        572,242
       Gas                                         9,849          8,557         32,448         30,357         56,560         51,418
       Other                                     120,668        115,228        225,393        213,152        446,697        454,842
                                             -----------    -----------    -----------    -----------    -----------    ------------
                                                 309,693        292,627        609,455        532,926      1,221,988      1,078,502
     Maintenance                                  80,400         67,617        132,660        118,240        261,555        225,360
     Depreciation and amortization                67,118         64,918        134,184        130,323        259,933        261,335
     Income taxes                                 60,872         49,647         89,484         80,902        239,273        228,024
   Other taxes                                    50,196         50,266         97,911         99,868        202,584        210,612
                                             -----------    -----------    -----------    -----------    -----------    ------------
       Total operating expenses                  568,279        525,075      1,063,694        962,259      2,185,333      2,003,833

 OPERATING INCOME                                114,013         96,292        179,788        165,179        457,877        438,415

 OTHER INCOME AND (DEDUCTIONS):
    Allowance for equity funds used
       during construction                         1,600          2,219          2,829          4,888          5,111          7,655
    Miscellaneous, net                             2,662          1,387          5,541          2,715         14,474         12,729
                                             -----------    -----------    -----------    -----------    -----------    ------------
       Total other income and (deductions)         4,262          3,606          8,370          7,603         19,585         20,384

 INCOME BEFORE
    INTEREST CHARGES                             118,275         99,898        188,158        172,782        477,462        458,799

 INTEREST CHARGES:
    Interest                                      33,548         31,055         66,014         61,978        124,014        127,105
    Allowance for borrowed funds
       used during construction                   (2,125)        (1,826)        (3,944)        (3,608)        (7,480)        (6,235)
                                             -----------    -----------    -----------    -----------    -----------    ------------
    Net interest charges                          31,423         29,229         62,070         58,370        116,534        120,870

 NET INCOME                                       86,852         70,669        126,088        114,412        360,928        337,929

 PREFERRED STOCK DIVIDENDS                         2,205          2,205          4,409          4,409          8,817          8,817
                                             -----------    -----------    -----------    -----------    -----------    ------------

NET INCOME AFTER PREFERRED
    STOCK DIVIDENDS                          $    84,647    $    68,464    $   121,679    $   110,003    $   352,111    $   329,112
                                             ===========    ===========    ===========    ===========    ===========    ===========

</TABLE>

See Notes to Financial Statements.

                                      -9-

<PAGE>

<TABLE>
<CAPTION>

                             UNION ELECTRIC COMPANY
                             STATEMENT OF CASH FLOWS
                                    UNAUDITED
                             (Thousands of Dollars)




                                                           Six Months Ended
                                                               June 30,
                                                          2000         1999
                                                          ----         ----
Cash Flows From Operating:
<S>                                                    <C>          <C>
   Net income                                          $ 126,088    $ 114,412
   Adjustments to reconcile net income to net cash
      provided by operating activities:
        Depreciation and amortization                    128,210      125,655
        Amortization of nuclear fuel                      18,342       21,025
        Allowance for funds used during construction      (6,773)      (8,496)
        Deferred income taxes, net                         6,725       (2,153)
        Deferred investment tax credits, net              (2,925)      (2,772)
        Changes in assets and liabilities:
           Receivables, net                              (89,935)     (39,729)
           Materials and supplies                         15,462      (18,532)
           Accounts and wages payable                    (46,124)     (59,123)
           Taxes accrued                                  59,656       71,859
           Other, net                                    (47,367)      63,718
                                                       ---------    ---------
Net cash provided by operating activities                161,359      265,864

Cash Flows From Investing:
   Construction expenditures                            (166,283)    (120,658)
   Allowance for funds used during construction            6,773        8,496
   Nuclear fuel expenditures                              (8,449)     (19,313)
   Intercompany notes receivable                          (3,420)    (145,500)
                                                       ---------    ---------
Net cash used in investing activities                   (171,379)    (276,975)

Cash Flows From Financing:
   Dividends on common
stock                                                   (138,150)    (123,161)
   Dividends on preferred stock                           (4,409)      (4,409)
   Redemptions -
         Nuclear fuel lease                               (3,933)      (7,427)
         Long-term debt                                 (186,500)          -
   Issuances -
         Nuclear fuel lease                                5,656       38,430
         Long-term debt                                  221,650       73,900
                                                       ---------    ---------
Net cash used in financing activities                   (105,686)     (22,667)

Net change in cash and cash equivalents                 (115,706)     (33,778)
Cash and cash equivalents at beginning of year           117,308       47,337
                                                       ---------    ---------
Cash and cash equivalents at end of period             $   1,602    $  13,559
                                                       =========    =========

Cash paid during the periods:
   Interest (net of amount capitalized)                $  58,958    $  58,025
   Income taxes, net                                   $  69,868    $  58,426

</TABLE>

See Notes to Financial Statements.

                                      -10-

<PAGE>


UNION ELECTRIC COMPANY
NOTES TO FINANCIAL STATEMENTS (UNAUDITED)
June 30, 2000

Note 1 - Union Electric Company  (AmerenUE or the Registrant) is a subsidiary of
Ameren  Corporation  (Ameren),  which is the  parent  company  of the  following
operating  companies:  the Registrant,  Central  Illinois Public Service Company
(AmerenCIPS) and AmerenEnergy  Generating  Company, a wholly owned subsidiary of
AmerenEnergy 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 AmerenUE and CIPSCO Incorporated (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 Missouri and  Illinois.
Contracts among the companies--dealing with jointly-owned 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 1.1 million  electric  and 124,000 gas  customers in a 24,500
square-mile area of Missouri and Illinois, including Metropolitan St. Louis.

The Registrant also has a 40 percent  interest in Electric  Energy,  Inc. (EEI),
which is  accounted  for under the  equity  method of  accounting.  EEI owns and
operates an  electric  generating  and  transmission  facility in Illinois  that
supplies  electric  power  primarily to a uranium  enrichment  plant  located in
Paducah, Kentucky.

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. 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 June 30, 2000 and 1999, are not  necessarily  indicative of trends for any
three-month, six-month or 12-month period.

Note 5 - In July 1995, the Missouri Public Service  Commission  (MoPSC) approved
an agreement  establishing  contractual  obligations  involving the Registrant's
Missouri  retail  electric  rates.   Included  was  a  three-year   experimental
alternative  regulation  plan  (the  Original  Plan)  that ran from July 1, 1995
through June 30, 1998,  which provided that earnings in those years in excess of
a 12.61%  regulatory  return on equity (ROE) be shared equally between customers
and  stockholders,  and earnings  above a 14% ROE be credited to customers.  The
formula for  computing  the credit  used  twelve-month  results  ending June 30,
rather than calendar year earnings.

The MoPSC staff proposed  adjustments  to the  Registrant's  estimated  customer
credit for the final year of the Original  Plan ended June 30, 1998,  which were
the  subject of  regulatory  proceedings  before the MoPSC in 1999.  In December
1999,  the MoPSC issued a Report and Order  (Order)  concerning  these  proposed
adjustments.  Based on the provisions of that Order, the Registrant  revised its
estimated final year credit to $31 million.  Subsequently, in December 1999, the
Registrant  filed a request for  rehearing  of the Order with the MoPSC,  asking
that  it  reconsider  its  decision  to  adopt  certain  of  the  MoPSC  staff's
adjustments.  The  request  was denied by the MoPSC and in  February  2000,  the
Registrant  filed a Petition

                                      -11-

<PAGE>

for Writ of Review with the Circuit Court of Cole County,  Missouri,  requesting
that the Order be reversed.  The appeal is pending and the ultimate  outcome can
not be  predicted;  however,  the final  decision is not expected to  materially
impact the  financial  condition,  results of  operations  or  liquidity  of the
Registrant.  A partial  stay of the Order was  granted by the Court  pending the
appeal.

 A new three-year  experimental  alternative  regulation plan (the New Plan) was
included in the joint  agreement  authorized  by the MoPSC in its February  1997
order  approving the Merger.  Like the Original Plan, the New Plan requires that
earnings  over a 12.61  percent  ROE up to a 14  percent  ROE be shared  equally
between  customers and  stockholders.  The New Plan also returns to customers 90
percent of all earnings above a 14 percent ROE up to a 16 percent ROE.  Earnings
above a 16 percent ROE are  credited  entirely to  customers.  The New Plan runs
from July 1, 1998 through June 30, 2001.  During the three months ended June 30,
2000, the Registrant recorded an estimated $5 million credit (2 cents per share)
for the plan year ended  June 30,  2000 that the  Registrant  expects to pay its
Missouri electric customers.  In total, the Registrant has recorded an estimated
credit of $35 million (15 cents per share) as of June 30, 2000 for the plan year
ended June 30, 2000,  compared to an estimated $20 million credit  recorded over
the same  period last year.  These  credits  were  reflected  as a reduction  in
electric  revenues.  The  final  amount of the  credit  will  depend on  several
factors,  including the Registrant's earnings for 12 months ended June 30, 2000.
As of June 30, 2000,  the Registrant has also reflected an estimated $25 million
credit it expects to pay its Missouri electric customers for the plan year ended
June 30, 1999.  The  Registrant's  proposed  credit is still under review by the
MoPSC staff and the Office of the Public Counsel.

The joint  agreement  approved by the MoPSC in its February 1997 Order approving
the Merger also provided for a Missouri  electric rate decrease,  retroactive to
September  1, 1998,  based on the  weather-adjusted  average  annual  credits to
customers  under the Original  Plan. The rate decrease was impacted by the Order
issued by the MoPSC in December 1999  relating to the  estimated  credit for the
third year of the Original Plan and a settlement reached between the Registrant,
the  MoPSC  staff  and  other  parties   relating  to  the  calculation  of  the
weather-adjusted  credits. Based on those results, the Registrant estimates that
its Missouri  electric rate decrease will be $17 million on an annualized basis.
This  estimate  is subject to the final  outcome of the  above-referenced  court
appeal of the Order.

Note 6 - 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  $46 million
and $15  million,  respectively,  as of June 30,  2000 and  December  31,  1999.
Intercompany   payables   included  in  accounts  and  wages   payable   totaled
approximately $43 million and $25 million, respectively, as of June 30, 2000 and
December 31, 1999.

Also, the Registrant has the ability to borrow up to approximately  $525 million
from  Ameren or  AmerenCIPS  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 June 30, 2000,  the Registrant had  outstanding  intercompany  receivables of
$169 million and $196 million available through the regulated money pool.

Note 7- The Company's  union  employees  are  represented  by the  International
Brotherhood  of  Electrical  Workers and the  International  Union of  Operating
Engineers.   These  employees  comprise   approximately  65%  of  the  Company's
workforce.   New  contracts  with  collective   bargaining   unit   representing
approximately 46% of these employees was ratified in 1999 with terms expiring in
2002. New contracts with collective bargaining units representing  approximately
28% of these  employees  were  ratified in 2000 with terms  expiring in 2003. On
July 27, 2000, after engaging in extensive good-faith bargaining with collective
bargaining  units  representing  approximately  26%  of the  Registrant's  union
employees,  the  Registrant  submitted  a last,  best  and  final  offer  to the
bargaining unit  representing  most of these employees for a new contract with a
term expiring in 2003. The  bargaining  unit has until August 25, 2000 to notify
the  Registrant  on whether the offer has been ratified by its  membership.  The
Registrant  is unable to  predict  whether  the offer will be  ratified  or what
action, if any, the collective  bargaining unit will take in the event

                                      -12-

<PAGE>

it is not ratified or the response of the Registrant's  other union  represented
employees  to any action by its  employees.  The  Registrant  is also  unable to
determine  what,  if any impact  these  labor  matters  could have on its future
financial condition, results of operations or liquidity.

Note 8- In 1998,  the  Registrant  joined a group of companies  that support the
formation of the Midwest  Independent  System  Operator  (Midwest  ISO).  An ISO
operates,  but does not own, electric  transmission systems and maintains system
reliability and security while  alleviating  certain  pricing  issues.  The FERC
conditionally  approved the  formation of the Midwest  ISO.  The  Registrant  is
evaluating  certain  issues  which are  outstanding  related to the  start-up of
operations  of the Midwest ISO,  including  the final  determination  of revenue
distribution  among  the  Midwest  ISO  members.   Further,  the  Registrant  is
evaluating  alternatives  to  membership  in the  Midwest  ISO.  At  this  time,
management  has not  decided its course of action  relative to its  transmission
business and accordingly is unable to determine the impact that operation of the
Midwest ISO or other alternatives will have on its financial condition,  results
of operations or liquidity.

                                      -13-

<PAGE>



                           PART II. OTHER INFORMATION


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

     Reference  is  made  to  Note 2 -  Regulatory  Matters  (Illinois  Electric
Restructuring)  in the Notes to Financial  Statements of the  Registrant's  Form
10-K for the year  ended  December  31,  1999,  for  information  relating  to a
transmission  system rate case filed by the  Registrant  with the Federal Energy
Regulatory  Commission (FERC) in August 1999. This filing was primarily designed
to implement rates, terms and conditions for electric  transmission  service for
those retail  customers in Illinois who choose other  suppliers as allowed under
the Electric  Service  Customer  Choice and Rate Relief Law of 1997.  On May 17,
2000, the FERC issued a letter order approving a settlement of this case reached
with the FERC trial staff and other interested parties.

     Reference  is  made  to  Item  1.  Legal  Proceedings  in  Part  II of  the
Registrant's  Form 10-Q for the  quarterly  period  ended  March 31,  2000,  for
information relating to the National Ambient Air Quality Standards for ozone and
particulate matter litigation.  On May 22, 2000, the United States Supreme Court
granted  certiorari  and agreed to review the United States Court of Appeals for
the  District of Columbia  Circuit's  decision to remand the ambient air quality
standard  regulations to the United States  Environmental  Protection Agency for
reconsideration.  At this time, the Registrant is unable to predict the ultimate
impact of those revised air quality standards on its future financial condition,
results of operation or liquidity.


ITEM 5.  OTHER INFORMATION
         -----------------

     Any stockholder  proposal  intended for inclusion in the proxy material for
the  Registrant's  2001 annual meeting of  stockholders  must be received by the
Registrant by November 30, 2000.

     In addition,  under the  Registrant's  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 the
Secretary of the  Registrant not later than 60 nor earlier than 90 days prior to
the  first  anniversary  of  the  preceding  year's  annual  meeting.   For  the
Registrant's  2001  annual  meeting  of  stockholders,  written  notice  of  any
in-person stockholder proposal or director nomination must be received not later
than February 24, 2001 or earlier than January 25, 2001.


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 June 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.

                             UNION ELECTRIC COMPANY
                                  (Registrant)


                                           By      /s/ Donald E. Brandt
                                              ------------------------------
                                                       Donald E. Brandt
                                                   Senior Vice President
                                               Finance and Corporate Services
                                                (Principal Financial Officer)


Date:  August 14, 2000


                                      -15-