<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM MCI
WORLDCOM, INC.'S FINANCIAL STATEMENTS FOR THE NINE MONTHS ENDED SEPTEMBER 30,
1999 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000,000

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JAN-01-1999
<PERIOD-END>                               SEP-30-1999
<CASH>                                             307
<SECURITIES>                                         0
<RECEIVABLES>                                    6,342
<ALLOWANCES>                                     1,102
<INVENTORY>                                          0
<CURRENT-ASSETS>                                 9,707
<PP&E>                                          29,957
<DEPRECIATION>                                  (4,056)
<TOTAL-ASSETS>                                  86,962
<CURRENT-LIABILITIES>                           15,553
<BONDS>                                         13,245
<PREFERRED-MANDATORY>                              798
<PREFERRED>                                          0
<COMMON>                                            19
<OTHER-SE>                                      49,298
<TOTAL-LIABILITY-AND-EQUITY>                    86,962
<SALES>                                              0
<TOTAL-REVENUES>                                27,131
<CGS>                                                0
<TOTAL-COSTS>                                   21,670
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                   658
<INTEREST-EXPENSE>                                 710
<INCOME-PRETAX>                                  4,795
<INCOME-TAX>                                     1,992
<INCOME-CONTINUING>                              2,711
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     2,663
<EPS-BASIC>                                       1.43
<EPS-DILUTED>                                     1.38