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

                                FORM 12b-25

                                          Commission File Number:  0-20298

                        NOTIFICATION OF LATE FILING

(Check one)

  Form 10-K and Form 10-KSB           Form 20-F   Form 11-K
- ---                      ---        ---
 X                         Form 10-Q and Form 10-QSB   Form N-SAR
- ---                      ---

For Period Ended June 30, 2003
              -----------------

     __            Transition Report on Form 10-K and Form 10-KSB
     __            Transition Report on Form 20-F
     __            Transition Report on Form 11-K
     __            Transition Report on Form 10-Q and Form 10-QSB
     __            Transition Report on Form N-SAR

     For the Transition Period Ended:
                                -----------------

   Nothing in this form shall be construed to imply that the Commission has
verified any information contained herein.

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

- -----------------------------------------------------------------------

PART I -- REGISTRANT INFORMATION

Full Name of Registrant: Southwest Royalties Institutional Income Fund X-C,
L.P.
                     ------------------------------------------------------

Former Name of Registrant:
                     ----------------------------

Address of Principal Executive Office (Street and Number):

407 North Big Spring, Suite 300
- ----------------------------------------------------------

City, State and Zip Code:

Midland, Texas 79701
- -------------------------



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,  the
following should be completed.

(Check box if appropriate):

[x]  (a)            The reasons 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 Forms 10-K, 10-KSB, Form 20-F, 11-K, Form  N-SAR,
     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 Forms 10-Q, 10-QSB, 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 the reasons why the Forms 10-K, 10-KSB, 20-
F,  11-K, 10-Q, 10-QSB, N-SAR, or the transition report or portion thereof,
could not be filed within the prescribed time period.  (Attach extra sheets
if needed)

   The  Partnership is in the review process with the SEC  in  response  to
comment letters dated May 28 and May 30, 2003.  The Partnership is  in  the
process  of  preparing amendments to it's previously issued 2002  10-K  and
March 31, 2003 10-Q based on the comment letters.  Once the Amendment No. 1
to  its  Annual  Report on Form 10-K for 2002 and March 31, 2003  Quarterly
Report  on  Form 10-Q have been filed, the Partnership will file it's  June
30, 2003 10-Q.

PART IV -- OTHER INFORMATION

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

     Lisa Hailes           (432) 686-9927
     -----------           --------------------------------
     (Name)                (Area code and 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 reports) been filed? If answer is
     no, identify report(s).
      X Yes      No
     ---         ---





(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?
      X Yes      No
     ---         ---

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

          On   January  1,  2003,  the  Partnership  adopted  Statement  of
     Financial   Accounting  Standards  No.  143,  Accounting   for   Asset
     Retirement Obligations ("SFAS No. 143").  Adoption of SFAS No. 143  is
     required for all companies with fiscal years beginning after June  15,
     2002.   The  new  standard  requires the Partnership  to  recognize  a
     liability  for  the present value of all legal obligations  associated
     with the retirement of tangible long-lived assets and to capitalize an
     equal amount as a cost of the asset and depreciate the additional cost
     over the estimated useful life of the asset.  On January 1, 2003,  the
     Partnership    recorded   additional   costs,   net   of   accumulated
     depreciation,  of  approximately $214,465, a long  term  liability  of
     approximately  $813,495 and a loss of approximately $599,030  for  the
     cumulative  effect  on  depreciation  of  the  additional  costs   and
     accretion  expense  on  the liability related to expected  abandonment
     costs  of  its oil and natural gas producing properties.  At June  30,
     2003,  the  asset retirement obligation was $839,801. The increase  in
     the  balance  from  January 1, 2003 is due  to  accretion  expense  of
     $32,420,  partially  offset by the sale of an oil  and  gas  property,
     which  decreased the asset retirement obligation by $6,114.   The  pro
     forma  amounts for the three and six months ended June 30, 2002, which
     are presented on the face of the statements of operations, reflect the
     effect of retroactive application of SFAS No. 143.

          In the fourth quarter of 2002, the Partnership changed methods of
     accounting  for  depletion  of capitalized costs  from  the  units-of-
     revenue  method to the units-of-production method.  The newly  adopted
     accounting  principle is preferable in the circumstances  because  the
     units-of-production method results in a better matching of  the  costs
     of  oil  and  gas production against the related revenue  received  in
     periods of volatile prices for production as have been experienced  in
     recent  periods.  Additionally, the units-of-production method is  the
     predominant  method used by full cost companies in  the  oil  and  gas
     industry,  accordingly, the change improves the comparability  of  the
     Partnership's   financial  statements  with  its  peer   group.    The
     Partnership   adopted  the  units-of-production  method  through   the
     recording  of a cumulative effect of a change in accounting  principle
     in  the  amount  of  $59,000 effective as of  January  1,  2002.   The
     Partnership's  depletion for the three and six months ended  June  30,
     2003  and  2002  has  been  calculated using  the  units-of-production
     method.   The  effect of the change on the three and six months  ended
     June  30,  2002 was to decrease income before cumulative effect  of  a
     change  in  accounting principle by $3,000 and $8,000 ($.50 and  $1.34
     per  limited partner unit), respectively and decrease and increase net
     income  by  $3,000  and $51,000 ($.50 and $8.52  per  limited  partner
     unit), respectively.



     

                                SIGNATURES


          Southwest Royalties Institutional Income Fund X-C, L.P.
         ---------------------------------------------------------
               (Name of Registrant as Specified in Charter)



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

     Dated: August 14, 2003   Southwest Royalties Institutional Income Fund
     X-C, L.P.



                           By: Southwest Royalties, Inc.,
                               Managing General Partner

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