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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 August 8,
2001, relating to the unaudited consolidated financial statements of AmSouth
Bancorporation and subsidiaries which are included in its Form 10-Q for the
quarter ended June 30, 2001:

   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;
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   Form S-8 No. 333-89633 pertaining to the First American Corporation First
Incentives Reward Savings Thrift Plan;

   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
August 8, 2001