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                                   EXHIBIT 15

Exhibit 15 -- Letter Re:  Unaudited Interim Financial Information

Board of Directors
AmSouth Bancorporation

We are aware of the incorporation by reference in the following Registration
Statements and in their related Prospectuses of our report dated April 23, 2002,
relating to the unaudited consolidated financial statements of AmSouth
Bancorporation and subsidiaries which are included in its Form 10-Q for the
quarter ended March 31, 2002:

     Form S-3 No. 33-55683 pertaining to the AmSouth Bancorporation Dividend
         Reinvestment and Common Stock Purchase Plan;
     Form S-8 No. 33-52243 pertaining to the assumption by AmSouth
         Bancorporation of FloridaBank Stock Option Plan and FloridaBank Stock
         Option Plan-1993;
     Form S-8 No. 33-52113 pertaining to the AmSouth Bancorporation 1989 Long
         Term Incentive Compensation Plan;
     Form S-8 No. 33-35218 pertaining to the AmSouth Bancorporation 1989 Long
         Term Incentive Compensation Plan;
     Form S-8 No. 33-37905 pertaining to the AmSouth Bancorporation Thrift Plan;
     Form S-8 No. 33-2927 (as amended) pertaining to the AmSouth Bancorporation
         Employee Stock Purchase Plan;
     Form S-3 No. 33-35280 pertaining to the AmSouth Bancorporation Dividend
         Reinvestment and Common Stock Purchase Plan;
     Form S-8 No. 333-02099 pertaining to the AmSouth Bancorporation Thrift
         Plan;
     Form S-8 No. 333-05631 pertaining to the AmSouth Bancorporation 1996 Long
         Term Incentive Compensation Plan;
     Form S-8 No. 333-27107 pertaining to the AmSouth Bancorporation Employee
         Stock Purchase Plan;
     Form S-8 No. 333-41599 pertaining to the AmSouth Bancorporation Deferred
         Compensation Plan and the Amended and Restated Deferred Compensation
         Plan for Directors of AmSouth Bancorporation;
     Form S-3 No. 333-44263 pertaining to the AmSouth Bancorporation Shelf
         Registration Statement;
     Form S-8 No. 333-76283 pertaining to the AmSouth Bancorporation Stock
         Option Plan for Outside Directors;
     Form S-8 No. 333-89451 pertaining to the First American Corporation 1993
         Non-Employee Director Stock Option Plan;
     Form S-8 No. 333-89455 pertaining to the First American Corporation 1999
         Broad-Based Employee Stock Option Plan;
     Form S-8 No. 333-89457 pertaining to the First American Corporation Star
         Award Plan;
     Form S-8 No. 333-89459 pertaining to the Deposit Guaranty Corporation Long
         Term Incentive Plans;
     Form S-8 No. 333-89461 pertaining to the First American Corporation 1991
         Employee Stock Incentive Plan;
     Form S-8 No. 333-89463 pertaining to the Heritage Federal Bancshares, Inc.
         1994 Stock Option Plan for Non-Employee Directors and 1992 Stock Option
         Plan and Incentive Compensation Plan for Non-Employee Directors;
     Form S-3 No. 333-42542 pertaining to the AmSouth Bancorporation Dividend
         Reinvestment and Common Stock Purchase Plan;
     Form S-8 No. 333-42554 pertaining to the AmSouth Bancorporation Thrift
         Plan;
     Form S-8 No. 333-42556 pertaining to the AmSouth Bancorporation Employee
         Stock Purchase Plan;
     Form S-8 No. 333-42558 pertaining to the AmSouth Bancorporation Amended and
         Restated 1991 Employee Stock Incentive Plan; and
     Form S-8 No. 333-42560 pertaining to the Pioneer Bancshares, Inc. Long-Term
         Incentive Plan.

Pursuant to Rule 436(c) of the Securities Act of 1933 our reports are not a part
of the registration statements prepared or certified by accountants within the
meaning of Sections 7 or 11 of the Securities Act of 1933.

                                        /s/  ERNST & YOUNG LLP

Birmingham, Alabama
April 23, 2002