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

                                    FORM 10-Q

(MARK ONE)
[X]      QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
                FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 1999

                                       OR

[ ]      TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934
             FOR THE TRANSITION PERIOD FROM ......... TO ..........
                          COMMISSION FILE NUMBER 1-7584


                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)


          DELAWARE                                             74-1079400
(STATE OR OTHER JURISDICTION OF                            (I.R.S. EMPLOYER
 INCORPORATION OR ORGANIZATION)                             IDENTIFICATION NO.)

    2800 POST OAK BOULEVARD
       P. O. BOX 1396
       HOUSTON, TEXAS                                            77251
(ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)                      (ZIP CODE)

REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE (713) 215-2000

                                      NONE
(FORMER NAME, FORMER ADDRESS AND FORMER FISCAL YEAR, IF CHANGED SINCE LAST
 REPORT)


         INDICATE BY CHECK MARK WHETHER THE REGISTRANT (1) HAS FILED ALL REPORTS
REQUIRED TO BE FILED BY SECTION 13 OR 15(d) OF THE  SECURITIES  EXCHANGE  ACT OF
1934  DURING  THE  PRECEDING  12 MONTHS  (OR FOR SUCH  SHORTER  PERIOD  THAT THE
REGISTRANT WAS REQUIRED TO FILE SUCH REPORTS),  AND (2) HAS BEEN SUBJECT TO SUCH
FILING REQUIREMENTS FOR THE PAST 90 DAYS. YES  X   NO
                                              ---    ---

THE NUMBER OF SHARES OF COMMON STOCK, PAR VALUE $1.00 PER SHARE, OUTSTANDING AS
OF SEPTEMBER 30, 1999 WAS 100.

REGISTRANT  MEETS THE CONDITIONS SET FORTH IN GENERAL  INSTRUCTIONS  H(1)(a) AND
(b) OF FORM  10-Q AND IS  THEREFORE  FILING  THIS  FORM  10-Q  WITH THE  REDUCED
DISCLOSURE FORMAT.


<PAGE>



                         PART I - FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS.

         COMPANY OR GROUP OF COMPANIES FOR WHICH REPORT IS FILED:

TRANSCONTINENTAL GAS PIPE LINE CORPORATION AND SUBSIDIARIES (TRANSCO)

     The accompanying  interim condensed  consolidated  financial  statements of
Transco do not include all notes in annual  financial  statements  and therefore
should be read in conjunction  with the  consolidated  financial  statements and
notes  thereto in Transco's  1998 Annual  Report on Form 10-K and 1999 First and
Second Quarter  Reports on Form 10-Q. The  accompanying  condensed  consolidated
financial  statements have not been audited by independent  auditors but include
all  adjustments  both  normal  recurring  and others  which,  in the opinion of
Transco's management,  are necessary to present fairly its financial position at
September  30,  1999,  and results of  operations  for the three and nine months
ended  September  30, 1999 and 1998,  and cash flows for the nine  months  ended
September 30, 1999 and 1998.

     Certain matters discussed in this report, excluding historical information,
include   forward-looking    statements.    Although   Transco   believes   such
forward-looking statements are based on reasonable assumptions, no assurance can
be given that every  objective  will be achieved.  Such  statements  are made in
reliance on the "safe harbor" protections  provided under the Private Securities
Reform  Act of 1995.  Additional  information  about  issues  that could lead to
material  changes in performance is contained in Transco's 1998 Annual Report on
Form  10-K,  1999 First and  Second  Quarter  Reports on Form 10-Q and Year 2000
disclosure contained in this document.





<PAGE>



                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION

                      CONDENSED CONSOLIDATED BALANCE SHEET
                             (Thousands of Dollars)
                                   (Unaudited)

<TABLE>
<CAPTION>
                                                                                 September 30,            December 31,
                                                                                      1999                    1998
                                                                                -----------------       -----------------

         ASSETS

<S>                                                                               <C>                     <C>
Current Assets:
     Cash                                                                         $      1,924            $       1,470
     Receivables:
         Affiliates                                                                        571                   10,892
         Others                                                                         20,187                   21,689
     Advances to affiliates                                                            460,399                  416,164
     Transportation and exchange gas receivables:
         Affiliates                                                                      1,590                    1,370
         Others                                                                         30,662                   56,475
     Inventories                                                                        74,798                   79,787
     Deferred income taxes                                                             107,560                   99,598
     Other                                                                              17,628                   16,714
                                                                                -----------------       -----------------
         Total current assets                                                          715,319                  704,159
                                                                                -----------------       -----------------

Long-term advances to affiliates                                                         7,398                        -
                                                                                -----------------       -----------------

Investments, at cost plus equity in undistributed earnings                              31,429                    8,915
                                                                                -----------------       -----------------

Property, Plant and Equipment:
     Natural gas transmission plant                                                  4,296,682                4,259,502
     Less-Accumulated depreciation and amortization                                    667,720                  616,120
                                                                                -----------------       -----------------
         Total property, plant and equipment, net                                    3,628,962                3,643,382
                                                                                -----------------       -----------------

Other Assets                                                                           175,816                  168,495
                                                                                -----------------       -----------------

                                                                                  $  4,558,924            $   4,524,951
                                                                                =================       =================


The accompanying condensed notes are an integral part of these condensed consolidated financial statements.
</TABLE>






<PAGE>



                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION

                CONDENSED CONSOLIDATED BALANCE SHEET (Continued)
                             (Thousands of Dollars)
                                   (Unaudited)

<TABLE>
<CAPTION>
                                                                              September 30,          December 31,
                                                                                  1999                   1998
                                                                             ----------------       ----------------

            LIABILITIES AND STOCKHOLDER'S EQUITY

<S>                                                                           <C>                    <C>
Current Liabilities:
     Payables:
         Affiliates                                                           $     68,927           $     25,050
         Others                                                                     68,149                 72,285
     Transportation and exchange gas payables:
         Affiliates                                                                    376                    379
         Others                                                                     11,137                  8,354
     Accrued liabilities                                                           127,218                156,631
     Reserve for rate refunds                                                      159,409                238,403
                                                                             ----------------       ----------------
         Total current liabilities                                                 435,216                501,102
                                                                             ----------------       ----------------

Long-Term Debt, less current maturities                                            975,443                975,768
                                                                             ----------------       ----------------

Other Long-Term Liabilities:
     Deferred income taxes                                                         858,538                846,306
     Other                                                                         113,811                139,734
                                                                             ----------------       ----------------
         Total other long-term liabilities                                         972,349                986,040
                                                                             ----------------       ----------------

Commitments and contingencies (Note 3)

Common Stockholder's Equity:
     Common stock $1.00 par value:
         100 shares authorized, issued and outstanding                                   -                      -
     Premium on capital stock and other paid-in capital                          1,652,430              1,652,430
     Retained earnings                                                             523,486                409,611
                                                                             ----------------       ----------------
         Total common stockholder's equity                                       2,175,916              2,062,041
                                                                             ----------------       ----------------

                                                                              $  4,558,924           $  4,524,951
                                                                             ================       ================


The accompanying condensed notes are an integral part of these condensed consolidated financial statements.
</TABLE>

<PAGE>



                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION

                   CONDENSED CONSOLIDATED STATEMENT OF INCOME
                             (Thousands of Dollars)
                                   (Unaudited)

<TABLE>
<CAPTION>
                                                                                     Three months ended
                                                                                        September 30
                                                                           ----------------------------------------
                                                                                 1999                   1998
                                                                           -----------------      -----------------
<S>                                                                        <C>                    <C>
Operating Revenues:
   Natural gas sales                                                       $     195,715          $     125,576
   Natural gas transportation                                                    152,964                160,753
   Natural gas storage                                                            33,825                 35,993
   Other                                                                           2,147                  1,811
                                                                           -----------------      -----------------
        Total operating revenues                                                 384,651                324,133
                                                                           -----------------      -----------------

Operating Costs and Expenses:
   Cost of natural gas sales                                                     195,715                125,576
   Cost of natural gas transportation                                              6,893                 11,938
   Operation and maintenance                                                      41,241                 44,311
   Administrative and general                                                     31,242                 30,852
   Depreciation and amortization                                                  40,268                 39,744
   Taxes - other than income taxes                                                 9,107                  9,305
   Other                                                                             901                  1,815
                                                                           -----------------      -----------------
        Total operating costs and expenses                                       325,367                263,541
                                                                           -----------------      -----------------

Operating Income                                                                  59,284                 60,592
                                                                           -----------------      -----------------

Other (Income) and Other Deductions:
   Interest expense                                                               20,282                 23,769
   Interest income - affiliates                                                   (6,640)                (7,241)
   Allowance for equity and borrowed funds used during construction (AFUDC)       (1,479)                (3,316)
   Miscellaneous other (income) deductions, net                                       37                   (236)
                                                                           -----------------      -----------------
        Total other deductions                                                    12,200                 12,976
                                                                           -----------------      -----------------

Income before Income Taxes                                                        47,084                 47,616

Provision for Income Taxes                                                        17,762                 18,000
                                                                           -----------------      -----------------

Net Income                                                                 $      29,322          $      29,616
                                                                           =================      =================


The accompanying condensed notes are an integral part of these condensed consolidated financial statements.
</TABLE>
<PAGE>


                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION

                   CONDENSED CONSOLIDATED STATEMENT OF INCOME
                             (Thousands of Dollars)
                                   (Unaudited)
<TABLE>
<CAPTION>

                                                                                      Nine months ended
                                                                                        September 30
                                                                           ----------------------------------------
                                                                                 1999                   1998
                                                                           -----------------      -----------------
<S>                                                                        <C>                    <C>
Operating Revenues:
   Natural gas sales                                                       $     512,063          $     401,533
   Natural gas transportation                                                    506,681                481,633
   Natural gas storage                                                           102,718                108,115
   Other                                                                           7,726                  6,660
                                                                           -----------------      -----------------
        Total operating revenues                                               1,129,188                997,941
                                                                           -----------------      -----------------

Operating Costs and Expenses:
   Cost of natural gas sales                                                     512,063                401,533
   Cost of natural gas transportation                                             28,534                 32,891
   Operation and maintenance                                                     123,550                127,051
   Administrative and general                                                     98,806                 92,241
   Depreciation and amortization                                                 120,655                111,526
   Taxes - other than income taxes                                                26,116                 27,091
   Other                                                                           2,673                  2,605
                                                                           -----------------      -----------------
        Total operating costs and expenses                                       912,397                794,938
                                                                           -----------------      -----------------

Operating Income                                                                 216,791                203,003
                                                                           -----------------      -----------------

Other (Income) and Other Deductions:
   Interest expense                                                               52,209                 69,158
   Interest income - affiliates                                                  (18,034)               (20,884)
   Allowance for equity and borrowed funds used during construction (AFUDC)       (3,473)                (7,989)
   Miscellaneous other deductions, net                                             1,756                    660
                                                                           -----------------      -----------------
        Total other deductions                                                    32,458                 40,945
                                                                           -----------------      -----------------

Income before Income Taxes                                                       184,333                162,058

Provision for Income Taxes                                                        70,458                 61,492
                                                                           -----------------      -----------------

Net Income                                                                 $     113,875          $     100,566
                                                                           =================      =================


   The  accompanying condensed notes are an integral part of these condensed consolidated financial statements.
</TABLE>
<PAGE>


                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION


                 CONDENSED CONSOLIDATED STATEMENT OF CASH FLOWS
                             (Thousands of Dollars)
                                   (Unaudited)
<TABLE>
<CAPTION>

                                                                                         Nine months ended
                                                                                            September 30
                                                                                  ---------------------------------
                                                                                      1999                1998
                                                                                  -------------       -------------

<S>                                                                               <C>                 <C>
Cash flows from operating activities:
   Net income                                                                     $  113,875          $  100,566
   Adjustments to reconcile  net income to net cash provided by operating
     activities:
       Depreciation and amortization                                                 124,528             116,413
       Deferred income taxes                                                           4,270              (2,370)
       Allowance for equity funds used during construction (AFUDC)                    (2,414)             (5,845)
       Changes in operating assets and liabilities:
          Receivables                                                                    (31)             18,836
          Receivables sold                                                            13,000             (12,000)
          Transportation and exchange gas receivables                                 25,593               1,589
          Inventories                                                                  4,989               1,603
          Payables                                                                    47,309             (22,994)
          Transportation and exchange gas payables                                     2,780              (6,818)
          Accrued liabilities                                                        (28,470)             23,183
          Reserve for rate refunds                                                   (78,994)            101,929
          Other, net                                                                 (37,726)            (32,377)
                                                                                  -------------       -------------
                Net cash provided by operating activities                            188,709             281,715
                                                                                  -------------       -------------
Cash flows from financing activities:
   Additions to long-term debt                                                            -              298,343
   Retirement of long-term debt                                                           -             (160,000)
   Debt issue costs                                                                       -               (2,060)
                                                                                  -------------       -------------
                Net cash provided by financing activities                                 -              136,283
                                                                                  -------------       -------------
Cash flows from investing activities:
   Property, plant and equipment:
       Additions, net of equity AFUDC                                               (108,590)           (233,807)
       Changes in accounts payable                                                    (7,596)             (9,552)
   Advances to affiliates, net                                                       (51,633)           (177,236)
   Investments in affiliates                                                         (21,331)             (1,919)
   Other, net                                                                            895               3,996
                                                                                  -------------       -------------
                Net cash used in investing activities                               (188,255)           (418,518)
                                                                                  -------------       -------------

Net increase (decrease) in cash                                                          454                (520)
Cash at beginning of period                                                            1,470               1,321
                                                                                  -------------       -------------
Cash at end of period                                                             $    1,924          $      801
                                                                                  =============       =============

Supplemental disclosures of cash flow information:
   Cash paid during the year for :
       Interest (exclusive of amount capitalized)                                 $   76,797          $   47,797
       Income taxes paid                                                              68,796              61,584
       Income tax refunds received                                                        -                  (77)


The accompanying condensed notes are an integral part of these condensed consolidated financial statements.
</TABLE>
<PAGE>


                   TRANSCONTINENTAL GAS PIPE LINE CORPORATION

              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS


                       1. CORPORATE STRUCTURE AND CONTROL

      Transcontinental Gas Pipe Line Corporation (Transco) is a wholly-owned
subsidiary of Williams Gas Pipeline Company (WGP).  WGP is a wholly-owned
subsidiary of The Williams Companies, Inc. (Williams).

                            2. BASIS OF PRESENTATION

      The condensed  consolidated  financial  statements include the accounts of
Transco and its majority-owned subsidiaries.  Companies in which Transco and its
subsidiaries  own 20  percent  to 50  percent  of the  voting  common  stock are
accounted  for  under  the  equity  method.  Equity in  earnings  and  losses of
unconsolidated affiliates is included in other operating revenues.

      The condensed  consolidated  financial  statements have been prepared from
the books and records of Transco without audit. Certain information and footnote
disclosures  normally  included in financial  statements  prepared in accordance
with generally  accepted  accounting  principles have been condensed or omitted.
These condensed  consolidated financial statements should be read in conjunction
with the  consolidated  financial  statements and the notes thereto  included in
Transco's  1998  Annual  Report on Form 10-K and 1999 First and  Second  Quarter
Reports on Form 10-Q.

      Through an agency agreement,  Williams Energy Services Company (WESCO), an
affiliate of Transco,  manages all jurisdictional merchant gas sales of Transco,
receives all margins  associated  with such  business  and, as Transco's  agent,
assumes  all market and credit risk  associated  with  Transco's  jurisdictional
merchant gas sales.  Consequently,  Transco's  merchant gas sales service has no
impact on its operating income or results of operations.

      Because of its rate structure and historical maintenance schedule, Transco
typically experiences lower operating income in the second and third quarters as
compared to the first and fourth quarters.

      Certain  reclassifications  have been made in the 1998  financial
statements to conform to the 1999 presentation.

                    3. CONTINGENT LIABILITIES AND COMMITMENTS

      There have been no new developments from those described in Transco's 1998
Annual Report on Form 10-K or 1999 First and Second Quarter Reports on Form 10-Q
other than as described below.
<PAGE>

RATE AND REGULATORY MATTERS

      PRODUCTION AREA RATE DESIGN (DOCKET NOS. RP92-137,  RP93-136 AND RP98-381)
Transco  has  expressed  to the  Federal  Energy  Regulatory  Commission  (FERC)
concerns  that  inconsistent  treatment  under  Order  636 of  Transco  and  its
competitor  pipelines with regard to rate design and cost  allocation  issues in
the  production  area  may  result  in  rates  which  could  make  Transco  less
competitive,  both in terms of production-area and long-haul  transportation.  A
hearing before a FERC  Administrative  Law Judge (ALJ) (Docket Nos. RP92-137 and
RP93-136),  dealing with,  among other things,  Transco's  production-area  rate
design,  concluded  in June 1994.  On July 19,  1995,  the ALJ issued an initial
decision finding that Transco's  proposed  production area rate design,  and its
existing use of a system wide cost of service and allocation of firm capacity in
the production area are unjust and unreasonable.  The ALJ therefore  recommended
that Transco divide its costs between its  production  area and market area, and
permit its customers to renominate their firm entitlements.

      On July 3, 1996,  the FERC issued an order on review of the ALJ's  initial
decision concerning,  among other things, Transco's production area rate design.
The FERC  rejected  the ALJ's  recommendations  that  Transco  divide  its costs
between  its  production  area and market  area,  and permit  its  customers  to
renominate  their firm  entitlements.  The FERC also  concluded that Transco may
offer firm service on its supply  laterals  through an open season and eliminate
its IT feeder service in favor of an interruptible  service option that does not
afford  shippers  feeding  firm  transportation  on  Transco's  production  area
mainline a priority  over other  interruptible  transportation.  On December 18,
1996,  the FERC denied  rehearing  of its July 3, 1996 Order.  Several  parties,
including Transco, have filed petitions for review in the United States Court of
Appeals for the District of Columbia  (D.C.  Circuit Court) of the FERC's orders
addressing  production  area rate design  issues.  On November 4, 1998, the D.C.
Circuit  Court issued an order  granting the FERC's motion to hold these appeals
in abeyance  pending  the outcome of the  proceedings  in  Transco's  Docket No.
RP98-381.  On October 7, 1999, in light of the FERC's orders rejecting Transco's
proposal  in  Docket  No.  RP98-381,  the D.C.  Circuit  Court  issued  an order
restoring the appeals to the active docket.

      TILDEN/MCMULLEN  FACILITIES SPIN-DOWN PROCEEDING (DOCKET NOS. CP98-236 AND
242) In  February  1998,  Transco  filed an  application  with the FERC  seeking
authorization  to abandon  Transco's  onshore  Tilden/McMullen  Gathering System
located in Texas by conveyance  to Williams Gas  Processing - Gulf Coast Company
(Gas   Processing),   an  affiliate   of  Transco.   Gas   Processing   filed  a
contemporaneous  request that the FERC declare that the facilities  sought to be
abandoned  would  be  considered  nonjurisdictional  gathering  facilities  upon
transfer to Gas  Processing.  In May 1999,  the FERC issued an order in which it
determined  that certain of the facilities  would be gathering  facilities  upon
transfer to Gas Processing,  i.e., 1) those facilities upstream of and including
the Tilden Plant, 2) the South McMullen and Goebel Laterals  located  downstream
of the Tilden Plant, and 3) the small,  short laterals which branch out from the
McMullen  Lateral  downstream  of the Tilden  Plant at several  points along its
length.  However,  the FERC determined that the McMullen Lateral itself, as well
as two compressor  units, are  jurisdictional  facilities,  but authorized their
abandonment  subject to Gas Processing  obtaining a certificate to operate those
facilities.  The net book value at  September  30,  1999 of the  Tilden/McMullen
facilities was  approximately  $67 million.  Operating income for the year ended
December 31, 1998 associated with those  facilities is estimated to be less than
$3 million;  however,  such operating  income may not be  representative  of the
effects of the  spin-down on Transco's  future  operating  income due to various
factors, including future regulatory actions. Transco's abandonment authority is
effective  for one year from the date of  issuance  of the order.  Transco  must
notify the FERC of the effective date of the  abandonment  within 10 days of the
transfer. On June 3, 1999, Transco and Gas Processing filed for rehearing of the
order with regard to the  facilities  classified  by the FERC as  jurisdictional
facilities, and on October 5, 1999, the FERC denied the rehearing request.
<PAGE>

LEGAL PROCEEDINGS

      OTHER LITIGATION In 1998, the United States Department of Justice informed
Williams  that Jack  Grynberg,  an  individual,  had filed  claims in the United
States  District  Court for the District of Colorado  under the False Claims Act
against  Williams  and  certain  of its  wholly  owned  subsidiaries,  including
Transco.  Mr.  Grynberg has also filed claims  against  approximately  300 other
energy  companies and alleges that the defendants  violated the False Claims Act
in connection  with the  measurement  and purchase of  hydrocarbons.  The relief
sought was an unspecified amount of royalties  allegedly not paid to the federal
government,  treble  damages,  a civil penalty,  attorneys'  fees, and costs. On
April 9, 1999,  the United States  Department of Justice  announced  that it was
declining  to intervene  in any of the  Grynberg  qui tam cases;  including  the
action filed against the Williams  entities in the United States  District Court
for the District of Colorado.  On October 21, 1999, the Panel on  Multi-District
Litigation  transferred  all of the Grynberg qui tam cases,  including  the ones
filed against Williams,  to the United States District Court for the District of
Wyoming for pre-trial purposes.

ENVIRONMENTAL MATTERS

      In July 1999,  Transco received a letter stating that the U.S.  Department
of Justice (DOJ),  at the request of the U.S.  Environmental  Protection  Agency
(EPA),  intends to file a civil action  against  Transco  arising from its waste
management  practices at  Transco's  compressor  stations and metering  stations
located in eleven (11) states from Texas to New Jersey. DOJ stated in the letter
that its complaint will seek civil penalties and injunctive relief under federal
environmental laws.

      DOJ offered to discuss  settlement of the claim and  discussions  began in
September  1999.  While no  specific  amount was  proposed,  DOJ stated that any
settlement must include an appropriate civil penalty for the alleged violations.

      Transco cannot reasonably estimate the amount of its potential liability,
if any, at this time.  However, Transco believes it has substantially  addressed
environmental  concerns on its system through ongoing voluntary remediation and
management programs.
<PAGE>

SUMMARY

      While no  assurances  may be  given,  Transco  does not  believe  that the
ultimate  resolution of the foregoing  matters and those  described in Transco's
1998  Annual  Report on Form 10-K and 1999 First and Second  Quarter  Reports on
Form 10-Q, taken as a whole and after consideration of amounts accrued, recovery
from customers,  insurance coverage or other indemnification arrangements,  will
have a materially  adverse  effect upon  Transco's  future  financial  position,
results of operations and cash flow requirements.

                       4. DEBT AND FINANCING ARRANGEMENTS

LONG-TERM DEBT

      Williams and certain of its subsidiaries,  including Transco,  are parties
to a $1 billion credit  agreement  (Credit  Agreement),  under which Transco can
borrow up to $400 million if the funds available under the Credit Agreement have
not been borrowed by Williams or other  subsidiaries.  Interest  rates vary with
current market  conditions based on the base rate of Citibank N.A.,  three-month
certificates of deposit of major United States money market banks, federal funds
rate or the  London  Interbank  Offered  Rate.  The  Credit  Agreement  contains
restrictions  which  limit,  under  certain   circumstances,   the  issuance  of
additional  debt,  the  attachment  of liens on any  assets  and any  change  of
ownership of Transco.  As of  September  30,  1999,  Transco had no  outstanding
borrowings under this agreement.

SHORT-TERM DEBT

      Transco is a party to a short-term  money market  facility  under which it
can borrow up to $40 million. Interest rates vary with current market conditions
based on the applicable bank rate at the time of the borrowings. As of September
30, 1999, Transco had no outstanding borrowings under these facilities.

SALE OF RECEIVABLES

      Transco  is a party to an  agreement  that  expires on  January  28,  2000
pursuant  to  which  Transco  can  sell to an  investor  up to $100  million  of
undivided  interest in certain of its trade  receivables.  At September 30, 1999
and December 31, 1998,  interests in these receivables held by the investor were
$100 million and $87 million, respectively.


<PAGE>


        ITEM 2. MANAGEMENT'S NARRATIVE ANALYSIS OF RESULTS OF OPERATIONS.

      The  following   discussion   should  be  read  in  conjunction  with  the
consolidated  financial  statements,  notes and management's  narrative analysis
contained in Items 7 and 8 of Transco's  1998 Annual  Report on Form 10-K and in
Transco's  1999  First  and  Second  Quarter  Reports  on Form 10-Q and with the
condensed consolidated financial statements and notes contained in this report.

                              RESULTS OF OPERATIONS

NET INCOME AND OPERATING INCOME

      Transco's  net income for the nine  months  ended  September  30, 1999 was
$113.9  million  compared  to net income of $100.6  million  for the nine months
ended September 30, 1998.  Operating  income for the nine months ended September
30, 1999 was $216.8 million compared to $203.0 million for the nine months ended
September 30, 1998. The higher  operating  income of $13.8 million was primarily
the result of higher transportation revenues and lower operation and maintenance
expense,  partially  offset by higher  administrative  and  general  expense and
depreciation  and  amortization  expense  discussed  below.  The increase in net
income was attributable to the increased operating income, as well as, lower net
interest  expense due  primarily to the  adjustment to reserves for rate refunds
discussed below and rate refunds made in 1998 and early 1999,  partially  offset
by lower  allowance  for funds used  during  construction  due to lower  capital
expenditures.

      Because of its rate structure and historical maintenance schedule, Transco
typically experiences lower operating income in the second and third quarters as
compared to the first and fourth quarters.

TRANSPORTATION REVENUES

      Transco's  operating revenues related to its  transportation  services for
the nine months ended  September  30, 1999 were $507  million,  compared to $482
million for the nine months ended September 30, 1998. The higher  transportation
revenues  were  primarily  due to a positive  adjustment to the reserve for rate
refunds in Transco's  general  rate case Docket No.  RP95-197  ($28.1  million),
benefits of expansion  projects  placed into service in 1998 ($13.4 million) and
new services begun in 1998 ($2.6 million). These increases were partly offset by
a decrease in commodity revenues ($8.6 million) due primarily to lower long-haul
and production-area  volumes, a lower level of reimbursable costs ($4.2 million)
that are included in operating expenses and recovered in Transco's rates and the
positive  impact  of a  $4  million  adjustment  recorded  in  1998  related  to
settlement  rates  contained in the January 1998  stipulation  and  agreement in
Transco's  general  rate case  Docket No.  RP97-71  approved by the FERC in June
1998.
<PAGE>

      During the first half of 1999, Transco engaged in an analysis of the court
appeal  related  to  Transco's  general  rate  case  Docket  No.  RP95-197  and,
particularly,   its  likely   results.   Based  on  developments  in  regulatory
proceedings  in the second  quarter of 1999  involving  Transco and others,  and
advice received from counsel,  Transco  adjusted its remaining  reserve for rate
refunds  ($28.1 million of principal and $5.9 million of interest) in the second
quarter of 1999 to reflect  the FERC's  revised  rate of return  methodology  as
applied in the July 29, 1998, and December 1, 1998 orders.

      As shown in the table below,  Transco's total  market-area  deliveries for
the nine months ended September 30, 1999 increased 41.7 trillion British Thermal
Units  (TBtu)  (4.1%) when  compared to the same period in 1998.  The  increased
deliveries  were  mainly due to higher  deliveries  under the Mobile Bay Lateral
Expansion Project and the Cherokee Expansion Project in the first nine months of
1999.  Transco's  production area deliveries for the nine months ended September
30, 1999 decreased 5.0 TBtu (3.0%) when compared to the same period in 1998 as a
result of milder weather conditions.

      As a result of a straight  fixed-variable (SFV) rate design,  increases or
decreases  in firm  transportation  volumes  in  comparable  facilities  have no
significant  impact  on  operating  income;   however,   because   interruptible
transportation  rates  have  components  of fixed and  variable  cost  recovery,
increases or decreases in interruptible transportation volumes do have an impact
on operating income.

                                                             Nine Months
                                                         Ended September 30,
                                                       -------------------------
Transco System Deliveries (TBtu)                         1999           1998
--------------------------------                       ----------     ----------

Market-area deliveries:
     Long-haul transportation                              626.8          651.3
     Market-area transportation                            435.2          369.0
                                                       ----------     ----------
         Total market-area deliveries                    1,062.0        1,020.3
Production-area transportation                             161.0          166.0
                                                       ----------     ----------
         Total system deliveries                         1,223.0        1,186.3
                                                       ==========     ==========

Average Daily Transportation Volumes (TBtu)                  4.5            4.3
Average Daily Firm Reserved Capacity (TBtu)                  6.3            6.4


     Transco's facilities are divided into seven rate zones. Four are located in
the  production  area and  three  are  located  in the  market  area.  Long-haul
transportation is gas that is received in one of the  production-area  zones and
delivered in a market-area zone. Market-area  transportation is gas that is both
received and delivered within market-area zones. Production-area  transportation
is gas that is both received and delivered within production-area zones.

     See Note 3 of the Notes to Condensed  Consolidated Financial Statements for
a discussion of recent developments in Transco's rate and regulatory matters.
<PAGE>




SALES REVENUES

     Transco makes jurisdictional  merchant gas sales to customers pursuant to a
blanket  sales  certificate  issued by the FERC,  with most of those sales being
made  through a Firm Sales (FS)  program  which  gives  customers  the option to
purchase  daily  quantities of gas from Transco at  market-responsive  prices in
exchange for a demand charge payment.

     Through an agency  agreement with Transco,  WESCO, an affiliate of Transco,
manages  Transco's  jurisdictional  merchant gas sales.  The long-term  purchase
agreements  managed by WESCO remain in Transco's  name, as do the  corresponding
sales of such purchased gas. Therefore,  Transco continues to record natural gas
sales revenues and the related accounts receivable and cost of natural gas sales
and the related accounts payable for the jurisdictional  merchant sales that are
managed by WESCO.  Through  the agency  agreement,  WESCO  receives  all margins
associated  with  jurisdictional  merchant gas sales  business and, as Transco's
agent,   assumes  all  market  and  credit  risk   associated   with   Transco's
jurisdictional  merchant gas sales.  Consequently,  Transco's merchant gas sales
service has no impact on Transco's  operating  income or results of  operations.
Transco's  operating  revenues  for the nine  months  ended  September  30, 1999
related to its sales services,  including Transco's cash out sales in settlement
of gas imbalances,  increased  $110.5 million to $512 million,  when compared to
the same period in 1998. The increase was primarily due to higher cash out sales
related to the  settlement  of  imbalances,  higher sales volumes and a slightly
higher average sales price.

                                                             Nine Months
                                                         Ended September 30,
                                                       -------------------------
Gas Sales Volumes (TBtu)                                1999             1998
------------------------                               --------         --------

Long-term sales                                          150.1            135.7
Short-term sales                                          28.1             18.3
                                                       --------         --------
    Total gas sales                                      178.2            154.0
                                                       ========         ========

STORAGE REVENUES

     Transco's  operating  revenues related to storage  services  decreased $5.4
million to $102.7  million for the nine  months  ended  September  30, 1999 when
compared  to the same  period in 1998.  This  revenue  decrease  included a $5.7
million decrease due to lower underground  storage rates charged by others,  the
majority of which is included in operation and  maintenance  expenses and a $1.2
million decrease primarily due to lower storage demand charges, partly offset by
the impact of an adjustment  recorded in 1998 to the revenue  refund  reserve to
reflect the actual rates contained in the RP97-71 Settlement Agreement.
<PAGE>

OPERATING COSTS AND EXPENSES

      Excluding  the cost of sales and  transportation  of $541  million for the
nine months ended September 30, 1999 and $434 million for the comparable  period
in 1998,  Transco's  operating  expenses for the nine months ended September 30,
1999,  were  approximately  $11.3 million higher than the  comparable  period in
1998.  This increase was primarily  attributable  to higher  administrative  and
general  expense and higher  depreciation  and  amortization  expense  partially
offset by lower operation and maintenance expense. The higher administrative and
general expense was primarily attributable to higher professional services ($1.5
million), building rent ($1.2 million), pension expense ($1.1 million) and labor
($2.3 million).  The higher  depreciation and amortization  expense was due to a
$3.8 million  adjustment  related to the RP97-71  settlement  rates  recorded in
1998, a $3.2 million adjustment on computer software recorded in 1998 and a $2.2
million increase in 1999,  primarily due to plant and property additions.  Lower
operation  and   maintenance   expense  was  primarily   attributable  to  lower
underground  storage rates charged by others ($5.5 million),  lower professional
services ($2.1 million) and lower  contractual  services ($1.5 million),  partly
offset by the effects of a $5.7 million  adjustment  recorded in 1998 related to
the RP97-71 settlement rates.

                         CAPITAL RESOURCES AND LIQUIDITY

METHOD OF FINANCING

     Transco  funds its  capital  requirements  with cash flows  from  operating
activities,  including  the  sale of trade  receivables,  by  accessing  capital
markets,  by repayments of funds advanced to Williams,  by borrowings  under the
Credit  Agreement  and  short-term  money  market  facilities  and, if required,
advances  from  Williams.  At  September  30,  1999,  there were no  outstanding
borrowings under the Credit Agreement or short-term money market facilities.

     As a participant  in Williams'  cash  management  program,  Transco and its
subsidiaries have made advances to Williams. At September 30, 1999, net advances
due Transco and its subsidiaries by Williams totaled $460 million. Additionally,
Transco has made  advances to WGP. At  September  30,  1999,  the  advances  due
Transco by WGP totaled $7.4 million and was classified as a long-term advance in
the accompanying Condensed Consolidated Balance Sheet.

CAPITAL EXPENDITURES AND INVESTMENTS IN AFFILIATES

     As shown in the table below, Transco's capital expenditures and investments
in affiliates for the nine months ended September 30, 1999 were $ 137.5 million,
compared to $245.3 million for the nine months ended September 30, 1998.
[CAPTION]
<TABLE>
                                                                            Nine Months
                                                                        Ended September 30,
                                                                       ----------------------
Capital Expenditures and Investments in Affiliates                      1999          1998
--------------------------------------------------                     ---------    ---------
                                                                           (In Millions)
<S>                                                                    <C>          <C>
Market-area projects                                                   $   25.5     $   79.9
Supply-area projects                                                       (1.8)       113.2
Maintenance of existing facilities and other projects                      92.5         50.3
Investments in affiliates                                                  21.3          1.9
                                                                       ---------    ---------
      Total capital expenditures and investments in affiliates         $  137.5     $  245.3
                                                                       =========    =========
</TABLE>

<PAGE>

      Transco's capital expenditures budget for 1999 and future capital projects
are  discussed in its 1998 Annual  Report on Form 10-K and 1999 First and Second
Quarter Reports on Form 10-Q. The following describes  significant  developments
related to those projects and any new projects proposed by Transco.

      BUCCANEER  PIPELINE  PROJECT On October 28, 1999,  Buccaneer  Gas Pipeline
Company,  L.L.C.  (Buccaneer),  a wholly-owned  subsidiary of Transco,  filed an
application  with the  Federal  Energy  Regulatory  Commission  for  certificate
authorization of its proposed  natural gas pipeline  project  extending from the
Mobile Bay area in Alabama to delivery points in Florida. The application states
that  Buccaneer's  pipeline  system will be designed to  transport up to 900,000
dekatherms  (dt) of natural gas per day.  The  proposed  in-service  date of the
pipeline  is April 1,  2002.  Buccaneer  estimates  that the  total  cost of the
project will be  approximately  $1.455  billion.  Buccaneer is proposing a 75/25
debt to equity capital structure and will seek non-recourse project financing.

      CARDINAL PIPELINE PROJECT On November 1, 1999, Cardinal Extension Company,
LLC, a North  Carolina  limited  liability  company  formed between wholly-owned
subsidiaries of Transco and three of Transco's North Carolina customers,  placed
its pipeline  project into service.  The project  involved the acquisition of an
existing   37-mile   pipeline  in  North  Carolina  and  the   construction   of
approximately  67 miles of pipeline to new  interconnections  in Clayton County,
North Carolina.  The pipeline provides  transportation  service of up to 270,000
Mcf of  natural  gas per  day.  The  total  cost to  complete  the  project  was
approximately  $98  million.  Transco's  wholly-owned   subsidiary  holds  a 45%
ownership interest in Cardinal. A separate wholly owned subsidiary of Transco is
the operator of Cardinal.

OTHER CAPITAL REQUIREMENTS AND CONTINGENCIES

      Transco's capital requirements and contingencies are discussed in its 1998
Annual  Report on Form 10-K and 1999  First and Second  Quarter  Reports on Form
10-Q.  Other than as described in Note 3 of the Notes to Condensed  Consolidated
Financial  Statements,  there have been no new developments from those described
in Transco's  1998 Annual Report on Form 10-K and 1999 First and Second  Quarter
Reports  on  Form  10-Q  with   regard  to  other   capital   requirements   and
contingencies.

      RATE  AND  REGULATORY  REFUNDS  Transco  has  provided  reserves  which it
believes are adequate for any rate refunds that may be required.
<PAGE>

      YEAR 2000 COMPLIANCE  Williams and its  wholly-owned  subsidiaries,  which
includes Transco,  initiated an  enterprise-wide  project in 1997 to address the
year 2000 compliance issue for both traditional and non-traditional  information
technology areas,  including embedded  technology which is prevalent  throughout
the  company.  The project  focuses on all  technology  hardware  and  software,
external  interfaces with customers and suppliers,  operations  process control,
automation and  instrumentation  systems,  and facility items. The phases of the
project are awareness,  inventory and  assessment,  renovation and  replacement,
testing  and   validation,   and   contingency   planning.   The  awareness  and
inventory/assessment  phases of this project as they relate to both  traditional
and non-traditional information technology areas have been completed. During the
inventory and assessment phase, all systems with possible year 2000 implications
were  inventoried  and classified  into five  categories:  1) highest,  business
critical,  2) high, compliance necessary within a short period of time following
January 1, 2000, 3) medium,  compliance necessary within 30 days from January 1,
2000,  4) low,  compliance  desirable  but  not  required,  and 5)  unnecessary.
Categories  1 through 3 were  designated  as critical and are the major focus of
this project.  Renovation/replacement and testing/validation of critical systems
has been  completed.  While  year 2000  date  processes  have been  successfully
validated,  ongoing  testing  will  continue to ensure data  integrity  and core
functionality.  Certain  non-critical systems may not be compliant by January 1,
2000.

      Testing and validation activities have been completed and at September 30,
1999,  100% of the  critical  systems  have been fully  tested or  validated  as
compliant. Year 2000 test labs remain in place and operational. As was expected,
few  problems  have  been  detected  during  testing  for items  believed  to be
compliant.

      Transco has initiated a formal communications process with other companies
with which  Transco's  systems  interface or rely on to determine  the extent to
which those companies are addressing their year 2000  compliance.  In connection
with this process,  Transco has sent more than 3,100 letters and  questionnaires
to third parties including customers, vendors, and service providers. Transco is
evaluating responses as they are received or otherwise  investigating the status
of these companies' year 2000 compliance efforts.  Because only approximately 21
percent of the companies  contacted have responded to this inquiry (all of these
have indicated that they are already  compliant or will be compliant on a timely
basis),  Transco has also been working  directly  with key business  partners to
reduce the risk of a break in service or supply and with non-compliant companies
to mitigate any material adverse effect on Transco.

      Transco has utilized both internal  resources and external  contractors to
complete  the year 2000  compliance  project.  Transco  has a core  group of 121
people assigned to this project. This group includes one individual  responsible
for  coordinating,  organizing,  managing,  communicating,  and  monitoring  the
project and another 120 part-time representatives responsible for completing the
project.  Depending  on which  phase  the  project  is in and what area is being
focused  on at any  given  point in time,  there can be an  additional  36 to 40
employees who are also contributing a portion of their time to the completion of
this project.  Transco has contracted with an external  contractor for a cost of
up to $6.0 million for the remediation of Transco's customer service system.
<PAGE>

      Although all critical  systems over which  Transco has control are planned
to be compliant and tested before the year 2000,  Transco has identified an area
that would equate to a most reasonably likely worst case scenario.  There is the
possibility of service interruptions due to non-compliance by third parties. For
example,  power  failures  along the  communications  network or  transportation
systems could cause service interruptions.  This risk should be minimized by the
enterprise-wide   communications  effort  with  and  evaluation  of  third-party
compliance plans and by the development of contingency plans. It is not possible
to quantify the possible  financial impact if this most reasonably  likely worst
case scenario were to come to fruition.

      Significant  focus on the  contingency  plan phase of the project has been
taking  place in 1999.  Guidelines  for the  contingency  planning  process were
issued in January  1999.  Contingency  plans have been  developed  for  critical
business   processes,   critical   business   partners,   suppliers  and  system
replacements that experience  significant  delays.  Transco's  contingency plans
include manning all operational  stations twenty-four hours a day, putting extra
security measures into place and stocking up on supplies.  In addition,  most of
Transco's   compressor   stations  are  capable  of   independently   generating
electricity in the event of a loss of electricity, and operation of the pipeline
can be done manually in case there is a loss of  telecommunications  capability.
These  plans are  subject  to  on-going  review  as we  continue  to assess  the
readiness of vendors and suppliers, and make changes as appropriate.

      Costs  incurred  for  new  software  and  hardware   purchases  are  being
capitalized  and other costs are being expensed as incurred.  Transco  currently
estimates  the total  cost of the  project,  including  any  accelerated  system
replacements, to be approximately $7.8 million. This $7.8 million has been or is
expected to be spent as follows:

      Prior to 1998 and during the first quarter of 1998,  Transco conducted the
     project  awareness  and  inventory/assessment  phases  of the  project  and
     incurred minimal costs.

      During  the  second  quarter  of  1998,  $0.1  million  was  spent  on the
     renovation/replacement  and testing/validation phases and completion of the
     inventory/assessment phase.

      The   third   and   fourth    quarters    of   1998,    focused   on   the
     renovation/replacement  and  testing/validation  phases and $2.1 million of
     costs were incurred.

      During   the   first   quarter   of   1999,   renovation/replacement   and
     testing/validation  continued,  contingency planning began and $2.0 million
     was expended.

      During  the  second   quarter  of  1999,  the  primary  focus  shifted  to
     testing/validation and contingency planning and $1.3 million was spent.

      During the third quarter of 1999, contingency planning continued and final
     testing began with $1.8 million spent.

      The fourth  quarter of 1999 will continue to focus mainly on completion of
     contingency  planning and final  testing  with $0.5 million  expected to be
     spent.

      The amount estimated to be spent during the first two quarters of 2000 for
     monitoring and problem resolution is considered minimal.
<PAGE>

      Virtually all of the $7.3 million incurred through  September 30, 1999 has
been expensed with a minimal amount  capitalized.  Of the $0.5 million of future
costs necessary to complete the project within the schedule described, virtually
all costs will be expensed,  with a minimal  amount  capitalized.  This estimate
does not  include  Transco's  potential  share of year  2000  costs  that may be
incurred by  partnerships  and joint ventures in which the company  participates
but is not the operator. The costs of previously planned system replacements are
not  considered  to be year 2000  costs and are,  therefore,  excluded  from the
amounts discussed above.

      The preceding discussion contains  forward-looking  statements  including,
without  limitation,  statements  relating to the company's  plans,  strategies,
objectives,  expectations,  intentions,  and adequate  resources,  that are made
pursuant to the "safe harbor"  provisions of the Private  Securities  Litigation
Reform Act of 1995. Readers are cautioned that such  forward-looking  statements
contained  in the year 2000  update are based on certain  assumptions  which may
vary from actual results.  Specifically, the dates on which the company believes
the year 2000 project will be completed and computer systems will be implemented
are based on management's best estimates,  which were derived utilizing numerous
assumptions of future events,  including the continued  availability  of certain
resources,  third-party modification plans and other factors. However, there can
be no guarantee that these estimates will be achieved, or that there will not be
a delay in, or increased costs associated with, the  implementation  of the year
2000 project.  Other specific factors that might cause  differences  between the
estimates and actual results  include,  but are not limited to, the availability
and cost of personnel  trained in these areas, the ability to locate and correct
all relevant computer code, timely responses to and corrections by third-parties
and suppliers,  the ability to implement  interfaces between the new systems and
the systems not being replaced,  and similar  uncertainties.  Due to the general
uncertainty inherent in the year 2000 problem,  resulting in large part from the
uncertainty  of the year 2000  readiness of  third-parties,  the company  cannot
ensure its ability to timely and  cost-effectively  resolve problems  associated
with the year 2000 issue that may affect its operations and business,  or expose
it to third-party liability.

CONCLUSION

      Although no assurances can be given,  Transco currently  believes that the
aggregate of cash flows from operating activities, supplemented, when necessary,
by repayments of funds advanced to Williams,  advances or capital  contributions
from Williams and  borrowings  under the Credit  Agreement or  short-term  money
market  facilities,  will provide Transco with sufficient  liquidity to meet its
capital requirements.  Transco also expects to access public and private markets
on reasonable terms to finance its capital requirements.



<PAGE>



                           PART II - OTHER INFORMATION


ITEM 1.  LEGAL PROCEEDINGS.

         See  discussion  in Note 3 of the Notes to  Condensed  Consolidated
         Financial Statements included herein.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K.

         (a) Exhibits.

             None

         (b) Reports on Form 8-K.

             None





<PAGE>





                                    SIGNATURE


Pursuant to the  requirements of Section 13 or 15(d) of the Securities  Exchange
Act of 1934,  the  Registrant  has duly  caused  this report to be signed on its
behalf by the undersigned, thereunto duly authorized.




                                              TRANSCONTINENTAL GAS PIPE LINE
                                              CORPORATION (Registrant)




Dated:  November 12, 1999                     By /s/ James C. Bourne
                                              -------------------------------

                                              James C. Bourne
                                              Controller
                                              (Principal Accounting Officer)