<ARTICLE> UT
<LEGEND>
This schedule contains summary financial information extracted from Southern
Investments UK plc Form 10-Q for the six months ended September 30, 1999, and is
qualified in its entirety by reference to such financial statements. Values are
in (pound) sterling.
</LEGEND>

<MULTIPLIER> 1,000,000
<CURRENCY> Pounds Sterling

                                              
<PERIOD-TYPE>                                      6-MOS
<FISCAL-YEAR-END>                                  MAR-31-2000
<PERIOD-START>                                     APR-1-1999
<PERIOD-END>                                       SEP-30-1999
<EXCHANGE-RATE>                                    1.6457
<BOOK-VALUE>                                       PER-BOOK
<TOTAL-NET-UTILITY-PLANT>                          1,264
<OTHER-PROPERTY-AND-INVEST>                           30
<TOTAL-CURRENT-ASSETS>                               217
<TOTAL-DEFERRED-CHARGES>                               0
<OTHER-ASSETS>                                       686
<TOTAL-ASSETS>                                     2,197
<COMMON>                                               0
<CAPITAL-SURPLUS-PAID-IN>                            902
<RETAINED-EARNINGS>                                  (11)
<TOTAL-COMMON-STOCKHOLDERS-EQ>                       891
<PREFERRED-MANDATORY>                                 50
<PREFERRED>                                            0
<LONG-TERM-DEBT-NET>                                 301
<SHORT-TERM-NOTES>                                   326
<LONG-TERM-NOTES-PAYABLE>                              0
<COMMERCIAL-PAPER-OBLIGATIONS>                         0
<LONG-TERM-DEBT-CURRENT-PORT>                          0
<PREFERRED-STOCK-CURRENT>                              0
<CAPITAL-LEASE-OBLIGATIONS>                            0
<LEASES-CURRENT>                                       0
<OTHER-ITEMS-CAPITAL-AND-LIAB>                       629
<TOT-CAPITALIZATION-AND-LIAB>                      2,197
<GROSS-OPERATING-REVENUE>                            129
<OTHER-OPERATING-EXPENSES>                            73
<TOTAL-OPERATING-EXPENSES>                            73
<OPERATING-INCOME-LOSS>                               56
<OTHER-INCOME-NET>                                   194
<INCOME-TAX-EXPENSE>                                  64
<INCOME-BEFORE-INTEREST-EXPEN>                       186
<TOTAL-INTEREST-EXPENSE>                              27
<NET-INCOME>                                         159
<PREFERRED-STOCK-DIVIDENDS>                            0
<EARNINGS-AVAILABLE-FOR-COMM>                          0
<COMMON-STOCK-DIVIDENDS>                              24
<TOTAL-INTEREST-ON-BONDS>                              0
<CASH-FLOW-OPERATIONS>                                81
<EPS-BASIC>                                          0
<EPS-DILUTED>                                          0