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                                                                    Exhibit 10-b

                             AMSOUTH BANCORPORATION
                            SUPPLEMENTAL THRIFT PLAN
                     Amended and Restated as of May 24, 2001

Article 1. The Plan

1.1 Establishment of the Plan

AmSouth Bancorporation (the "Company") established the AmSouth Bancorporation
Supplemental Thrift Plan for eligible employees of the Company and participating
Affiliates, effective as of January 1, 1995. This plan shall be known as the
AmSouth Bancorporation Supplemental Thrift Plan (the "Plan").

1.2 Purpose of the Plan

The Plan is intended to restore benefits that are cut back as a result of
certain legal limits that apply to the AmSouth Bancorporation Thrift Plan.

The group of eligible employees shall be limited to a "select group of
management or highly compensated employees" within the meaning of ERISA Section
201(2).

Benefits provided under this Plan shall be paid solely from the general assets
of the Company and participating Affiliates. This Plan, therefore, is exempt
from the participation, vesting, funding and fiduciary requirements of Title I
of ERISA. The Company may establish a rabbi trust (the "Trust") which may be
used to pay benefits arising under the Plan and all costs, charges and expenses
relating thereto; except that, to the extent that the funds held in the Trust
are insufficient to pay such benefits, costs, charges and expenses, the Company
shall pay such benefits, costs, charges and expenses.

1.3 Applicability of the Plan

This Plan applies only to eligible Employees who are in the active employ of the
Company or a participating Affiliate on or after January 1, 1995.

Article II. Definitions

Whenever used in the Plan, the following terms shall have the meanings set forth
below unless otherwise expressly provided. When the defined meaning is intended,
the term is capitalized. The definition of any term in the singular shall also
include the plural.

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2.1 Account

Account means the bookkeeping account for each Participant that represents the
Participant's total interest under the Plan. A Participant's Account consists of
the following subaccounts:

(a)    Salary Reduction Contributions Account means the portion of the
       Participant's Account attributable to salary reduction contributions made
       on the Participant's behalf under Section 4. 1, including any gains and
       losses credited on such contributions under Section 5.2.

(b)    Matching Contributions Account means the portion of the Participant's
       Account attributable to matching contributions made by the Employer on
       the Participant's behalf under Section 4.2 including any gains and losses
       credited on such contributions under Section 5.2.

2.2 Affiliate

Affiliate means--

(a)    AmSouth Bancorporation, and

(b)    any other entity which, along with the Company, is a member of a
       controlled group of employers under Code Section 414(b), (c), (m), or
       (o).

2.3    Beneficiary

A Participant's Beneficiary under this Plan shall be the same person or entity
designated as the Participant's beneficiary under the Thrift Plan.

2.4 Board

Board means the Company's Board of Directors.

2.5 Code

Code means the Internal Revenue Code of 1986, as amended, or as it may be
amended from time to time. A reference to a particular section of the Code shall
also be deemed to refer to the regulations under that Code section.

2.6 Company

Company means AmSouth Bancorporation or any successor thereto.

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2.7  Compensation

Compensation for any Plan Year means a Participant's "Compensation" as defined
under the Thrift Plan, without regard to any limits on such Compensation imposed
by Code section 401(a)(17).

2.8  Employee

Employee means any person who is employed by the Company or an Affiliate.

2.9  Employer

Employer means the Company and each Affiliate which has adopted this Plan for
its eligible Employees.

2.10 ERISA

ERISA means the Employee Retirement Income Security Act of 1974, as amended, or
as it may be amended from time to time. A reference to a particular section of
ERISA shall also be deemed to refer to the regulations under that section.

2.11 Participant

Participant means an Employee of an Employer who has met, and continues to meet,
the eligibility requirements of Section 3. 1.

2.12 Plan

Plan means the AmSouth Bancorporation Supplemental Thrift Plan, as amended from
time to time.

2.13 Plan Administrator

Plan Administrator means the AmSouth Benefits Committee.

2.14 Plan Year

Plan Year means the calendar year.

2.15 Thrift Plan

Thrift Plan means the AmSouth Bancorporation Thrift Plan, which is a defined
contribution profit sharing plan with a cash or deferred arrangement qualified
under Code Sections 401(a), (k) and (m) as amended from time to time.

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2.16 Termination of Service

Termination of Service means an Employee's death or resignation, discharge, or
retirement from the Company and its Affiliates.

2.17 Valuation Date

Valuation Date means the last day of each calendar quarter and any other date
that the Plan Administrator selects in its sole discretion for the revaluation
and adjustment of Accounts.

Article III. Participation

3.1  Eligibility

(a)  Any Employee who is eligible to participate in the Thrift Plan and whose
     annual base salary including amounts not currently includible in gross
     income under Code sections 125, 401(k) or 402(a)(8) but excluding special
     pay, bonuses or other incentive pay, reimbursement for expenses, special
     supplements for automobile or club dues and the Prior Profit Sharing Plan
     Bonus ("Base Salary") as of January 1, 1995 is equal to or greater than
     $150,000 shall be a Participant in this Plan as of January 1, 1995.

(c)  Any other Employee who is eligible to participate in the Thrift Plan and
     whose annual base salary including amounts not currently includible in
     gross income under Code sections 125, 401(k) or 402(a)(8) but excluding
     special pay, bonuses or other incentive pay, reimbursement for expenses,
     special supplements for automobile or club dues and the Prior Profit
     Sharing Plan Bonus ("Base Salary") is equal to or greater than $150,000 as
     of January 1 of any year shall be a Participant in this Plan as of that
     January 1. Any employee hired during the year whose Base Salary is equal to
     or greater than $150,000 on the date of hire shall be a Participant
     immediately.

(d)  Any other Employee shall be a Participant on the first day of the month
     immediately following the date he or she is designated in writing as a
     Participant in this Plan by the Chief Executive Officer of the Company or
     his designee.

However, no Employee shall become a Participant unless the Employee is a member
of a "select group of management or highly compensated employees" within the
meaning of ERISA Section 201(2).

3.2  Duration

An Employee who becomes a Participant under section 3.1 shall remain an active
Participant until his or her Termination of Service. No contributions shall be
credited to the Account of an individual after his active participation has been
terminated. However, such individual shall

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continue to be a Participant for all other purposes until all benefits to which
he or she is entitled to receive under this Plan have been paid.

Article IV Benefits

4.1 Salary Reduction Contributions

(a)  Salary Reduction Agreement. Each Participant in this Plan may execute a
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     supplemental salary reduction agreement on a form prescribed by the Plan
     Administrator. On this form the Participant may elect to reduce his or her
     Compensation for the Plan Year by a whole percentage that does not exceed
     fifteen percent (15%). The supplemental salary reduction agreement shall be
     executed prior to the first day of the Plan Year for which it is to be
     effective or, in the case of a Participant who first becomes eligible to
     participate in the Plan during the Plan Year, the supplemental salary
     reduction agreement shall be executed within 30 days of initial eligibility
     under this Plan effective for Compensation earned subsequent to the
     election. The supplemental salary reduction agreement for any Plan Year
     shall be irrevocable for such Plan Year. Moreover, an election for a Plan
     Year shall remain in full force and effect for all subsequent Plan Years
     unless modified or revoked by the Participant in writing to the Plan
     Administrator before the first day of the Plan Year for which such
     modification or revocation is to be effective. Notwithstanding the
     preceding sentence, a supplemental salary reduction agreement shall be
     revoked automatically once a Participant ceases to be an active Participant
     as set forth in Section 3.2 of this Plan.

(b)  Effectiveness of Salary Reduction Agreement. A Participant's supplemental
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     salary reduction agreement shall take effect and amounts specified in the
     supplemental salary reduction agreement shall begin to be credited to such
     Participant's Salary Reduction Contributions Account at such time as the
     Participant has made the maximum pre-tax elective deferrals to the Thrift
     Plan allowed by Code Section 402(g) or by the provisions of the Thrift
     Plan.

(c)  Allocation. Salary reduction contributions shall be allocated to the
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     Participant's Salary Reduction Contributions Account as of the last day of
     each calendar quarter within the Plan Year.

4.2 Employer Matching Contributions

(a)  Eligibility. A Participant shall be credited with matching contributions
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     under this Plan for such Plan Year at such time as the Participant ceases
     to receive a matching contribution under Section 4.01 of the Thrift Plan
     regardless of whether such Participant's supplemental salary reduction
     agreement has become effective as provided in Section 4.1 (b) above.

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(b)  Amount. The amount of matching contributions credited to a Participant's
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     account under this Plan shall be equal to 100% of the sum of (i) and (ii)
     below:

               (i)  the Participant's unmatched (determined on a per payroll
               basis) pre-tax elective deferrals made to the Thrift Plan
               pursuant to Section 4.02 of the Thrift Plan; and

               (ii) salary reduction contributions credited to the Participant's
               account under this Plan pursuant to the Participant's
               supplemental salary reduction agreement.

          Provided, however, that (A) no matching contributions shall be made on
          salary reduction Contributions or deferrals under (i) or (ii) above to
          the extent that such salary reduction contributions or deferrals
          (determined on a per payroll basis) exceed six percent (6%) of a
          Participant's Compensation; and (B) nothing in this Section 4.2 shall
          entitle a Participant to be credited with a matching contribution
          under this Plan for any salary reduction contribution or deferral made
          to the Thrift Plan prior to the time such Participant has received the
          maximum matching contributions to the Thrift Plan allowed under the
          terms of the Thrift Plan.

(c)  Allocations. Matching contributions shall be allocated to the Participant's
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     Matching Contributions Account as of the last day of each calendar quarter
     within the Plan Year.

4.3 Forfeitability of Benefits.

Participants shall have a 100% vested and nonforfeitable right to the balance of
their Account under this Plan at all times, subject, however, to the substantial
risk of forfeiture set forth in Section 5.3.

4.4 Change in Control.

Notwithstanding anything in the Plan to the contrary, in the event that a
Participant is employed by the Company (or any entity that must be treated as a
single employer with the Company pursuant to Section 414(b), (c), (m) or (o) of
the Code) at the time of a Change in Control (as defined herein), the
Participant shall (regardless of whether he has become a Retiree or attained age
55 on the date of his termination of employment) be entitled to a lump sum
payment of a retirement benefit under the Plan (determined as if he were to
become a Retiree upon termination of employment) if the Participant's employment
with the Company (or any entity that must be treated as a single employer with
the Company pursuant to Section 414(b), (c), (m) or (o) of the Code) terminates
within two (2) years after a Change in Control has occurred.

For purposes of this Plan, a "Change in Control" shall mean:
     (a) The acquisition by any individual, entity or group (within the meaning
of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"))

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(a"Person") of beneficial ownership (within the meaning of Rule 13d-3
promulgated under the Exchange Act) of 20% or more of either (i) the then
outstanding shares of common stock of the Company (the "Outstanding Company
Common Stock") or (ii) the combined voting power of the then outstanding voting
securities of the Company entitled to vote generally in the election of
directors (the "Outstanding Company Voting Securities"); provided, however, that
for purposes of this subsection (a), the following acquisitions shall not
constitute a Change in Control: (i) any acquisition directly from the Company,
(ii) any acquisition by the Company, (iii) any acquisition by any employee
benefit plan (or related trust) sponsored, maintained by the Company or any
corporation controlled by the Company or (iv) any acquisition by any corporation
pursuant to a transaction which complies with clauses (i), (ii) and (iii) of
subsection (c) of this section; or
     (b) Individuals who, as of the date hereof, constitute the Board (the
"Incumbent Board") cease for any reason to constitute at least a majority of the
Board; provided, however, that any individual becoming a director subsequent to
the date hereof whose election, or nomination for election by the Company's
shareholders, was approved by a vote of at least a majority of the directors
then comprising the Incumbent Board shall be considered as though such
individual were a member of the Incumbent Board, but excluding, for this
purpose, any such individual whose initial assumption of office occurs as a
result of an actual or threatened election contest with respect to the election
or removal of directors or other actual or threatened solicitation of proxies or
consents by or on behalf of a Person other than the Board; or
     (c) Consummation of a reorganization, merger or consolidation or sale or
other disposition of all or substantially all of the assets of the Company (a
"Business Combination"), in each case, unless, following such Business
Combination, (i) all or substantially all of the individuals and entities who
were the beneficial owners, respectively, of the Outstanding Company Common
Stock and Outstanding Company Voting Securities immediately prior to such
Business Combination beneficially own, directly or indirectly, more than 60% of,
respectively, the then outstanding shares of common stock and the combined
voting power of the then outstanding voting securities entitled to vote
generally in the election of directors, as the case may be, of the corporation
resulting from such Business Combination (including, without limitation, a
corporation which as a result of such transaction owns the Company or all or
substantially all of the Company's assets either directly or through one or more
subsidiaries) in substantially the same proportions as their ownership,
immediately prior to such Business Combination of the Outstanding Company Common
Stock and Outstanding Company Voting Securities, as the case may be, (ii) no
Person (excluding any corporation resulting from such Business Combination or
any employee benefit plan or related trust of the Company or such corporation
resulting from such Business Combination) beneficially owns, directly or
indirectly, 20% or more of, respectively, the then outstanding shares of common
stock of the corporation resulting from such Business Combination or the
combined voting power of the then outstanding voting securities of such
corporation except to the extent that the such ownership existed prior to the
Business Combination and (iii) at least a majority of the members of the board
of directors of the corporation resulting from such Business Combination were
members of the Incumbent Board at the time of the execution of the initial
agreement, or the action of the Board, providing for such Business Combination;
or
     (d) Approval by the shareholders of the Company of a complete liquidation
or dissolution of the Company.

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Article V. Accounts; Financing

5.1 Participant Accounts

Each contribution credited to a Participant under Article IV shall be allocated
to an individual bookkeeping Account maintained on behalf of that Participant by
the Plan Administrator. Each Participant's Account shall be adjusted for
earnings in the manner described in Section 5.2.

5.2 Valuation of Participant Accounts

As of each Valuation Date, each Participant's Account shall be adjusted to
reflect earnings as follows. An average of the Participant's Account (the
"Average Account Balance") shall be obtained by dividing (a) the sum of (i) the
Participant's Account as of the immediately preceding Valuation Date and (ii)
the Participant's Account as of the immediately preceding Valuation Date plus
all contributions since the immediately preceding Valuation Date, by (b) two.
The Participant's Average Account Balance shall be multiplied by the Applicable
Interest Rate, and this product shall be added to or subtracted from the
Participant's Account. The Applicable Interest Rate shall be determined by
calculating the percentage (either positive or negative) obtained by dividing
the Participant's net earnings or losses of all funds in the Thrift Plan as of
the Valuation Date by the Participant's average Thrift Plan balance. The
Participant's average Thrift Plan balance shall be calculated by dividing (a)
the sum of (i) the Participant's total balance in the Thrift Plan as of the
Valuation Date and (ii) the Participant's total balance in the Thrift Plan as of
the immediately preceding Valuation Date, by (b) two.

5.3 Financing

The benefits under this Plan shall be paid out of the general assets of the
Employers (including assets held in the Trust). No Participant or Beneficiary
shall have any interest in any specific asset of any Employer. To the extent
that any person acquires a right to receive payments under this Plan, such right
shall be no greater than the right of any unsecured general creditor of any
Employer. Nothing contained in this Plan, and no action taken pursuant to the
provisions of this Plan, shall create a fiduciary relationship between an
Employer and any Participant or Beneficiary or a right of continued employment
for any Participant.

Article VI.  Distributions

6.1 Termination of Service

Upon a Participant's Termination of Service, the Participant shall be entitled
to the balance of his or her Account. This balance shall be paid to the
Participant in a lump sum cash payment within 90 days of the Valuation Date
immediately following the Participant's Termination of Service.

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6.2 Death of the Participant

If the Participant dies before the distribution of his or her Account, the
balance in the Account shall be distributed to the Participant's Beneficiary in
a lump sum cash payment within 90 days of the Valuation Date immediately
following the Participant's death.

6.3 No In-Service Withdrawals

A Participant may not receive a distribution from his or her Account before
incurring a Termination of Service.

Article VII Administration

7.1 Administration

The Plan shall be administered by the Plan Administrator. The Plan Administrator
shall have all powers necessary or appropriate to carry out the provisions of
the Plan. It may, from time to time, establish rules for the administration of
the Plan and the transaction of the Plan's business. The Plan Administrator
shall have absolute and complete discretionary authority to interpret and
administer the Plan and shall have the exclusive right to make any finding of
fact necessary or appropriate for any purpose under the Plan including, but not
limited to, the determination of eligibility for and amount of any benefit. The
Plan Administrator shall have the exclusive right to interpret the terms and
provisions of the Plan and to determine any and all questions arising under the
Plan or in connection with its administration, including, without limitation,
the right to remedy or resolve possible ambiguities, inconsistencies, or
omissions by general rule or particular decision, all in its sole and absolute
discretion. To the extent permitted by law, all finding of fact, determinations,
interpretations, and decisions of the Plan Administrator shall be conclusive and
binding upon all persons having or claiming to have any interest or right under
the Plan. The Plan Administrator may, in its sole and absolute discretion,
delegate any of its powers and duties under this Plan to one or more
individuals. In such a case, every reference in the Plan to the Plan
Administrator shall be deemed to include such matters within their jurisdiction.
The Plan Administrator shall have the right to consult with attorneys and other
advisors regarding its duties under this Plan, which attorney and advisors may
be employed by an Employer.

7.2 Appeals from Denial of Claims

If any claim for benefits under the Plan is wholly or partially denied, the
claimant shall be given notice of the denial. This notice shall be in writing,
within a reasonable period of time after receipt of the claim by the Plan
Administrator. This period shall not exceed 90 days after receipt of the claim,
except that if special circumstances require an extension of time, written

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notice of the extension shall be furnished to the claimant, and an additional 90
days will be considered reasonable.

This notice shall be written in a manner calculated to be understood by the
claimant and shall set forth the following information:

(a)  the specific reasons for the denial;

(b)  specific reference to the Plan provisions on which the denial is based;

(c)  a description of any additional material or information necessary for the
     claimant to perfect the claim and an explanation of why this material or
     information is necessary;

(d)  an explanation that a full and fair review by the Committee of the decision
     denying the claim may be requested by the claimant or an authorized
     representative by filing with the Committee, within 60 days after the
     notice has been received, a written request for the review; and

(e)  if this request is so filed, an explanation that the claimant or an
     authorized representative may review pertinent documents and submit issues
     and comments in writing within the same 60-day period specified in
     subsection (d).

The Committee's actions shall be in accordance with Section 2.06 of the Thrift
Plan.

7.3 Tax Withholding

The Employer may withhold from any payment under this Plan any federal, state,
or local taxes required by law to be withheld with respect to the payment and
any sum the Employer may reasonably estimate as necessary to cover any taxes for
which it may be liable and that may be assessed with regard to the payment.

7.4 Expenses

All expenses incurred in the administration of the Plan shall be paid by the
Employers.

Article VIII. Adoption of the Plan by Affiliate; Amendment and Termination of
the Plan

8.1 Adoption of the Plan by Affiliate

All Affiliates of the Company are deemed to have adopted this Plan as of the
later of (i) the effective date of this Plan as set forth in Section 1.1 or (ii)
the date of such Affiliate's affiliation with the Company.

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8.2 Amendment and Termination

The Company hereby reserves the right to amend, modify or terminate the Plan at
any time and for any reason by action of the Board or the Committee. However, no
amendment or termination shall adversely affect the amount of benefits accrued
by a Participant prior to the date of the amendment or termination.

Article IX. Miscellaneous Provisions

9.1 Nonalienation

No benefit payable under the Plan shall be subject in any manner to
anticipation, alienation, sale, transfer, assignment, pledge, encumbrance, or
charge. Any attempt to anticipate, alienate, sell, transfer, assign, pledge,
encumber, or charge shall be void. Benefits shall not be in any manner subject
to the debts, contracts, liabilities, engagements, or torts of, or claims
against, any Participant or Beneficiary, including claims of creditors, claims
for alimony or support, and any other like or unlike claims.

9.2 Distribution to Minors & Incompetents

In making any distribution to or for the benefit of any minor or incompetent
person, the Plan Administrator, in its sole and absolute discretion, may, but
need not, direct such distribution to a legal or natural guardian or other
relative of such minor or court appointed committee of such incompetent, or to
any adult with whom such minor or incompetent temporarily or permanently
resides, and any such guardian, committee, relative or other person shall have
full authority and discretion to expend such distribution for the use and
benefit of such minor or incompetent. The receipt of such guardian, committee,
relative or other person shall be a complete discharge to the Company and any
Employer hereunder without any responsibility on its part or on the part of the
Plan Administrator to see to the application thereof.

9.3 Severability

If any provision of this Plan shall be held illegal or invalid, the illegality
or invalidity shall not affect its remaining parts. The Plan shall be construed
and enforced as if it did not contain the illegal or invalid provision.

9.4 Applicable Law

Except to the extent preempted by applicable federal law, this Plan shall be
governed by and construed in accordance with the laws of the state of Alabama.

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In Witness Whereof, AmSouth Bancorporation, on behalf of itself and all
participating Affiliates, has caused its authorized officers to execute this
document on September 14, 2001, effective as of May 24, 2001.

                                             AMSOUTH BANCORPORATION


                                             By   /s/ C. Dowd Ritter
                                               ---------------------------------
ATTEST:                                      Its: Chairman, President and
                                                  Chief Executive Officer

/s/ Michelle A. Bridges
-------------------------------
Its: Assistant Secretary

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