<TABLE> <S> <C>

<PAGE>

<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED STATEMENT OF CONDITION, THE CONSOLIDATED STATEMENT OF EARNINGS, THE
CONSOLIDATED STATEMENT OF CASH FLOWS OF ITEM 1 OF PART I AND TABLES 2, 5, 6 AND
7 OF ITEM 2 OF PART I OF THE AMSOUTH BANCORPORATION FORM 10-Q FOR THE THREE
MONTHS ENDED MARCH 31, 2000.
</LEGEND>
<RESTATED>
<MULTIPLIER> 1,000

<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-2000             DEC-31-1999
<PERIOD-START>                             JAN-01-2000             JAN-01-1999
<PERIOD-END>                               MAR-31-2000             MAR-31-1999
<CASH>                                       1,541,259               1,452,441
<INT-BEARING-DEPOSITS>                               0                   4,655
<FED-FUNDS-SOLD>                                57,843                 119,931
<TRADING-ASSETS>                                31,923                  63,416
<INVESTMENTS-HELD-FOR-SALE>                  5,974,961               7,524,835
<INVESTMENTS-CARRYING>                       6,969,210               4,381,355
<INVESTMENTS-MARKET>                         6,756,448               4,388,875
<LOANS>                                     26,617,471              24,684,518
<ALLOWANCE>                                    363,492                 366,243
<TOTAL-ASSETS>                              43,680,465              40,405,804
<DEPOSITS>                                  28,344,315              27,358,042
<SHORT-TERM>                                 5,357,405               4,361,568
<LIABILITIES-OTHER>                            570,923                 698,222
<LONG-TERM>                                  6,398,678               4,741,871
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                       416,949                 420,753
<OTHER-SE>                                   2,592,195               2,825,348
<TOTAL-LIABILITIES-AND-EQUITY>              43,680,465              40,405,804
<INTEREST-LOAN>                                562,307                 505,071
<INTEREST-INVEST>                              215,670                 180,579
<INTEREST-OTHER>                                 4,721                   8,312
<INTEREST-TOTAL>                               782,698                 693,962
<INTEREST-DEPOSIT>                             245,575                 219,375
<INTEREST-EXPENSE>                             414,125                 325,173
<INTEREST-INCOME-NET>                          368,573                 368,789
<LOAN-LOSSES>                                   25,400                  18,734
<SECURITIES-GAINS>                               3,266                   6,154
<EXPENSE-OTHER>                                355,357                 340,744
<INCOME-PRETAX>                                207,853                 212,076
<INCOME-PRE-EXTRAORDINARY>                     207,853                 212,076
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                   138,937                 136,796
<EPS-BASIC>                                       0.35                    0.35
<EPS-DILUTED>                                     0.35                    0.34
<YIELD-ACTUAL>                                    3.77                    4.17
<LOANS-NON>                                    122,365                 112,328
<LOANS-PAST>                                    66,375                  65,737
<LOANS-TROUBLED>                                     0                       0
<LOANS-PROBLEM>                                      0                       0
<ALLOWANCE-OPEN>                               363,476                 373,756
<CHARGE-OFFS>                                   40,377                  38,842
<RECOVERIES>                                    14,993                  12,595
<ALLOWANCE-CLOSE>                              363,492                 366,243
<ALLOWANCE-DOMESTIC>                                 0                       0
<ALLOWANCE-FOREIGN>                                  0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0


</TABLE>