UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 12b-25

                           NOTIFICATION OF LATE FILING



(Check one):  |X| Form 10-K    |_| Form 20-F    |_| Form 11-K    |_| Form 10-Q
              |_| Form  N-SAR  |_| Form N-CSR

         For Period Ended:  December 31, 2003
         |_| Transition Report on Form 10-K
         |_| Transition  Report on Form 20-F
         |_| Transition  Report on Form 11-K
         |_| Transition Report on Form 10-Q
         |_| Transition Report on Form N-SAR
         For the Transition Period Ended:  December 31, 2003
                                         ---------------------------------------

If the notification  relates to a portion of the filing checked above,  identify
the Item(s) to which the notification relates:

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PART I - REGISTRANT INFORMATION

Southwest Oil & Gas Income Fund XI-A LP
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Full Name of Registrant

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Former Name if Applicable

407 North Big Spring, Suite 300
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Address of Principal Executive Office (Street and Number)

Midland, TX 79701
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City, State and Zip Code

PART II - RULES 12b-25(b) AND (c)

If the subject report could not be filed without  unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

      (a)      The reason  described  in  reasonable  detail in Part III of this
               form  could  not be  eliminated  without  unreasonable  effort or
               expense

 [X]  (b)      The subject annual report,  semi-annual report, transition report
               on Form 10-K,  Form 20-F, Form 11-K, Form N-SAR or form N-CSR, or
               portion  thereof,  will  be  filed  on or  before  the  fifteenth
               calendar day  following the  prescribed  due date; or the subject
               quarterly  report or  transition  report on Form 10-Q, or portion
               thereof,  will be filed  on or  before  the  fifth  calendar  day
               following the prescribed due date; and

      (c)      The  accountant's  statement  or other  exhibit  required by Rule
               12b-25(c) has been attached if applicable.





PART III - NARRATIVE

State below in reasonable detail why Forms 10-K, 20-F, 11-K, 10-Q, N-SAR, N-CSR,
or the  transition  report or  portion  thereof,  could not be filed  within the
prescribed time period.

Southwest  Oil & Gas Income Fund XI-A,  L.P.  (the  "Partnership")  received its
reserve  report  from Ryder  Scott & Co. late this year.  The  Managing  General
Partner of the Partnership is responsible for filing Annual Reports on Form 10-K
for 19 limited  partnerships that require information from reserve reports to be
included in their  financial  statements and because of the late delivery of the
reserve  reports for these  partnerships,  KPMG, the  Partnership's  independent
auditors,  will not be able to complete its audit of the Partnership's financial
statements by March 30, 2004.

PART IV - OTHER INFORMATION

   (1)    Name and  telephone  number  of person  to  contact  in regard to this
          notification

                  Lisa Hailes                  (432)                686-9927
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                  (Name)                     (Area Code)      (Telephone Number)

   (2)    Have all other periodic  reports required under Section 13 or 15(d) of
          the  Securities  Exchange Act of 1934 or Section 30 of the  Investment
          Company Act of 1940 during the preceding 12 months or for such shorter
          period that the  registrant  was required to file such  report(s) been
          filed? If answer is no, identify reports.

                       |X|Yes                    |_|No

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   (3)    Is it anticipated that any significant change in results of operations
          from  the  corresponding  period  for the  last  fiscal  year  will be
          reflected  by the  earnings  statements  to be included in the subject
          report or portion thereof?

                       |_|Yes                    |X|No

          Of  so,  attach  an  explanation  of  the  anticipated  changes,  both
          narratively and quantitatively, and, if appropriate, state the reasons
          why a reasonable estimate of the results cannot be made.

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                   Southwest Oil & Gas Income Fund XI-A, L.P.
                  --------------------------------------------
                  (Name of Registrant as Specified in Charter)

          has  caused  this  notification  to be  signed  on its  behalf  by the
          undersigned hereunto duly authorized.

Date:  March 29, 2004                    Southwest Royalties, Inc.
      -------------------                The Managing General Partner

                                         By: /s/ H. H. Wommack
                                            ------------------------------------
                                            H.H. Wommack, III
                                            Chairman of the Board, President and
                                            Chief Executive Officer