<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED FINANCIAL STATEMENTS OF S1 CORPORATION FOR THE TWELVE MONTHS ENDED
DECEMBER-31-1999 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
CONSOLIDATED FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   12-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JAN-01-1999
<PERIOD-END>                               DEC-31-1999
<CASH>                                          67,850
<SECURITIES>                                    62,754
<RECEIVABLES>                                   78,720
<ALLOWANCES>                                     8,584
<INVENTORY>                                          0
<CURRENT-ASSETS>                               209,543
<PP&E>                                          35,794
<DEPRECIATION>                                  11,214
<TOTAL-ASSETS>                               1,132,487
<CURRENT-LIABILITIES>                          113,317
<BONDS>                                              0
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                     11,354
<COMMON>                                     1,127,095
<OTHER-SE>                                   (147,642)
<TOTAL-LIABILITY-AND-EQUITY>                 1,132,487
<SALES>                                              0
<TOTAL-REVENUES>                                92,890
<CGS>                                                0
<TOTAL-COSTS>                                   53,089
<OTHER-EXPENSES>                               167,125
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                   0
<INCOME-PRETAX>                              (125,087)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                          (125,087)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                 (125,087)
<EPS-BASIC>                                     (4.28)
<EPS-DILUTED>                                   (4.28)