<ARTICLE>                                           UT
<LEGEND>
This schedule contains summary financial  information extracted from the balance
sheet, income statement,  and cash flow statement of Illinova Corporation and is
qualified in its entirety by reference to the balance sheet,  income  statement,
and cash flow statement of Illinova Corporation.

</LEGEND>
<CIK>                         0000914755
<NAME>                        Illinova Corporation
<SUBSIDIARY>
   <NUMBER>                   0
   <NAME>                     0
<MULTIPLIER>                                   1,000,000
<CURRENCY>                                     Default

                             
<PERIOD-TYPE>                   9-mos
<FISCAL-YEAR-END>                              Dec-31-1999
<PERIOD-START>                                 Jan-01-1999
<PERIOD-END>                                   Sep-30-1999
<EXCHANGE-RATE>                                1
<BOOK-VALUE>                                   Per-book
<TOTAL-NET-UTILITY-PLANT>                      4489
<OTHER-PROPERTY-AND-INVEST>                    270
<TOTAL-CURRENT-ASSETS>                         672
<TOTAL-DEFERRED-CHARGES>                       760
<OTHER-ASSETS>                                 0
<TOTAL-ASSETS>                                 6191
<COMMON>                                       976
<CAPITAL-SURPLUS-PAID-IN>                      0
<RETAINED-EARNINGS>                            14
<TOTAL-COMMON-STOCKHOLDERS-EQ>                 990
<PREFERRED-MANDATORY>                          193
<PREFERRED>                                    47
<LONG-TERM-DEBT-NET>                           1944
<SHORT-TERM-NOTES>                             107
<LONG-TERM-NOTES-PAYABLE>                      175
<COMMERCIAL-PAPER-OBLIGATIONS>                 280
<LONG-TERM-DEBT-CURRENT-PORT>                  236
<PREFERRED-STOCK-CURRENT>                      0
<CAPITAL-LEASE-OBLIGATIONS>                    0
<LEASES-CURRENT>                               0
<OTHER-ITEMS-CAPITAL-AND-LIAB>                 2219
<TOT-CAPITALIZATION-AND-LIAB>                  6191
<GROSS-OPERATING-REVENUE>                      1928
<INCOME-TAX-EXPENSE>                           56
<OTHER-OPERATING-EXPENSES>                     1673
<TOTAL-OPERATING-EXPENSES>                     1729
<OPERATING-INCOME-LOSS>                        199
<OTHER-INCOME-NET>                             29
<INCOME-BEFORE-INTEREST-EXPEN>                 228
<TOTAL-INTEREST-EXPENSE>                       151
<NET-INCOME>                                   77
<PREFERRED-STOCK-DIVIDENDS>                    1
<EARNINGS-AVAILABLE-FOR-COMM>                  78
<COMMON-STOCK-DIVIDENDS>                       64
<TOTAL-INTEREST-ON-BONDS>                      96
<CASH-FLOW-OPERATIONS>                         77
<EPS-BASIC>                                  1.12
<EPS-DILUTED>                                  1.12