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                                                                    EXHIBIT 10.9

                                 AMENDMENT NO. 4
                      TO SOUTHWEST AIRLINES CO. 401(k) PLAN


         Pursuant to the authority of the Board of Directors of Southwest
Airlines Co., and the provisions of Section 17.1 thereof, the Southwest Airlines
Co. 401(k) Plan (the "Plan") is hereby amended in the following respects only,
effective as specifically provided herein.


         (1) Article II, Section 2.1(v), is hereby amended, effective only if
the Morris Air Corporation Employee Retirement Plan (the "Morris Plan") is
merged in whole or in part into the Plan and in that event, effective as of the
date of such merger (the "Merger Date"), to read as follows:

                  "(v) Member: An Employee who has met the eligibility
         requirements for participation in this Plan, as set forth in Article
         III hereof. A former Member is a Member who has terminated employment
         with the Company but who has an Individual Account under the Plan, and
         shall include those individuals who have an Individual Account under
         the Plan and who were not employed by the Company, but who were
         formerly employed by Morris Air Corporation.

         (2) Article III, Section 3.1, is hereby amended in its entirety,
effective December 1, 2003, to read as follows:

                  "3.1 Eligibility Requirements: Every Employee on the Effective
         Date, who was a Member in the Prior Plan on the day before the
         Effective Date, shall continue to be a Member in the Plan. Except as
         otherwise provided herein, every other Employee shall be eligible to
         become a Member in the Plan as of the first Entry Date concurrent with
         or next following his employment commencement date. The employment
         commencement date is the first day for which an Employee is entitled to
         be credited hereunder with an Hour of Service. Non-resident aliens who
         receive no earned income from the Company that constitutes income from
         sources within the United States shall not be eligible to participate
         in the Plan. Furthermore, "leased employees" (as such term is defined
         in Section 2.1(n) hereof) and Employees classified by the Company as
         interns shall not be eligible to participate in the Plan. A person who
         is not treated as an Employee on the Company's books and records (such
         as a person who as a matter of practice is treated by the Company as an
         independent contractor, but who is later determined to be an Employee
         as a matter of fact) shall not be an eligible Employee during any part
         of a Plan Year in which such person was not treated as an Employee,
         despite any retroactive recharacterization."



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         (3) Article X, Section 10.4, is hereby amended in its entirety,
effective January 1, 2002, to read as follows:

                  "10.4 Forfeitures for Cause: In the event a Member who has not
         completed at least three (3) years of Vesting Service is discharged due
         to his dishonest or criminal act (proven by conclusive evidence to the
         unanimous satisfaction of the Committee) or due to embezzlement, fraud,
         or dishonesty against and damaging to the Company whereby the reasons
         for such discharge are confirmed by resolution of the board of
         directors or other governing authority of the Company, the entire
         amount credited to the benefit of such Member in his Company Matching
         Contribution Account shall be forfeited and neither he nor his
         Beneficiary shall be entitled to any benefit hereunder with respect to
         such amounts. Likewise, any amounts credited, but not distributed, to
         the Company Matching Contribution Account of a former Member who has
         not completed at least three (3) years of Vesting Service shall be
         forfeited upon the discovery of any embezzlement, fraud, or dishonesty
         of such former Member against and damaging to the Company.
         Notwithstanding the foregoing, in the event the Plan is top-heavy for
         any Plan Year, pursuant to Section 19.2 hereof, the provisions of
         Section 10.1 shall supercede this Section 10.4 and shall be controlling
         for all purposes hereunder."

         (4) Article XI, Section 11.1, the third paragraph, is hereby amended,
effective only if the Morris Plan is merged in whole or in part into the Plan
and in that event, effective as of the Merger Date, to read as follows:

                  "The minimum amount that may be loaned is the sum of: (i) One
         Thousand and No/100 Dollars ($1,000.00) and (ii) an amount equal to the
         Plan's loan administration fee in effect on the date on which the loan
         is made. Only one loan from the Plan per calendar year may be approved
         for any Member, and no more than one such loan may be outstanding at
         any time. Notwithstanding the foregoing, if, immediately prior to the
         merger of the Morris Air Corporation Employee Retirement Plan (the
         "Morris Air Plan") into this Plan, a Member had an outstanding loan
         under this Plan and an outstanding loan under the Morris Air Plan, then
         both such loans may remain outstanding. Loans shall be granted by the
         Committee in a uniform and nondiscriminatory manner. Each loan shall
         bear a reasonable rate of interest and be adequately secured and shall
         by its terms require repayment in no later than five years, unless such
         loan is used to acquire any dwelling unit that within a reasonable time
         is to be used (determined at the time the loan is made) as a principal
         residence of the Member. All loans shall be repaid pro rata to the
         applicable account from which the loan proceeds were paid pursuant to a
         salary deduction procedure established by the Company unless the Member
         is on an authorized leave of absence, transfers to a location that does
         not participate in a salary deduction procedure, or is subject to a
         proceeding in bankruptcy that does not permit payments by salary
         deduction, in which case payment may be made to the principal office of
         the Company by check."



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         (5) Article XI, Section 11.2(b), is hereby amended in its entirety,
effective only if the Morris Plan is merged in whole or in part into the Plan
and in that event, effective as of the Merger Date, to read as follows:

                  "(b) Attainment of Age 59 1/2. A Member who has attained the
         age of fifty-nine and one-half (59 1/2) may elect, in writing, within
         the time period established by the Committee for such elections, to
         withdraw all or any portion of his vested interest (determined pursuant
         to Section 10.1 hereof) in his Individual Account. Any partial
         withdrawal shall be taken from such Member's Individual Account as
         follows: first, from the after-tax amounts, if any, in the Member's
         Individual Account until such amounts are fully depleted; second, from
         the Member's Rollover Contribution Account until such account is fully
         depleted; third, from the Member's Salary Reduction Contribution
         Account until such account is fully depleted; and fourth, from the
         Member's Company Matching Contribution Account until such account is
         fully depleted. No more than one such withdrawal may be made by the
         Member during any Plan Year. The amount available for withdrawal shall
         be determined as of the Valuation Date next following the date on which
         the Committee receives the Member's withdrawal election, and the
         withdrawal amount shall be distributed to the Member as soon as
         practicable thereafter."

         (6) Article XI is hereby amended to add Section 11.2(c), effective only
if the Morris Plan is merged in whole or in part into the Plan and in that
event, effective as of the Merger Date, to read as follows:

                  "(c) Withdrawals from Rollover Contribution Account: A Member
         may elect, in writing, within the time period established by the
         Committee for such elections, to withdraw all or any portion of his
         Rollover Contribution Account. No more than one such withdrawal may be
         made by the Member during any Plan Year. The amount available for
         withdrawal shall be determined as of the Valuation Date next following
         the date on which the Committee receives the Member's withdrawal
         election, and the withdrawal amount shall be distributed to the Member
         as soon as practicable thereafter."

         (7) Section 1 of Amendment No. 3 to Southwest Airlines Co. 401(k) Plan,
is hereby amended, effective January 1, 1997 through December 31, 2001, to read
as follows:

                  "(a) The 'deferral percentage' for each Employee who is then
         eligible for Salary Reduction Contributions, which shall be the ratio
         of the amount of such Employee's Salary Reduction Contributions for
         such Plan Year to such Employee's compensation (as defined in Section
         2.1(r) hereof) for such Plan Year;"

         IN WITNESS WHEREOF, and as conclusive evidence of the adoption of the
foregoing instrument comprising Amendment No. 4 to the Southwest Airlines Co.
401(k) Plan, the



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Company has caused these presents to be duly executed in its name and behalf by
its proper officers thereunto duly authorized this 22nd day of December, 2003.

                                    SOUTHWEST AIRLINES CO.


                                    By:    /s/ James F. Parker
                                        ----------------------------------------
                                        James F. Parker, Chief Executive Officer
ATTEST:


        /s/ Deborah Ackerman
-------------------------------------
Deborah Ackerman, Assistant Secretary



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STATE OF TEXAS            )
                          )
COUNTY OF DALLAS          )

         BEFORE ME, the undersigned, a Notary Public in and for said County and
State, on this 22nd day of December, 2003, personally appeared JAMES F. PARKER,
to me known to be the identical person who subscribed the name of SOUTHWEST
AIRLINES CO., as its CHIEF EXECUTIVE OFFICER to the foregoing instrument and
acknowledged to me that he executed the same as his free and voluntary act and
deed and as the free and voluntary act and deed of such organization for the
uses and purposes therein set forth.

         GIVEN UNDER MY HAND AND SEAL OF OFFICE, the day and year last above
written


                                         /s/
                                     -------------------------------------------
                                     Notary Public in and for the State of Texas



My Commission Expires:
                      ---------------



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