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                                                                      EXHIBIT 6

Pricing Supplement No. 1 dated November 18, 2003            CUSIP # 89353Z BM 9
(To a short form base shelf prospectus dated
November 20, 2002, and prospectus supplement
dated November 29, 2002)

                               [TRANSCANADA LOGO]

                           MEDIUM TERM NOTE DEBENTURES
                                   (UNSECURED)

                          TRANSCANADA PIPELINES LIMITED

Amount of Issue (Cdn. $):          $450,000,000
Date of Debentures:                November 21, 2003
Delivery Date:                     November 21, 2003
Issue Price (%):                   99.764%
Proceeds (Cdn. $):                 $448,938,000
Less Agent Commission (%, $):      0.40%, $1,800,000
Maturity Date:                     January 15, 2014

Redemption Provisions:             The Corporation may redeem the Medium Term
                                   Note Debentures referred to herein on the
                                   terms and conditions and in the manner
                                   described below under the heading
                                   "Redemption Provisions". The Government of
                                   Canada Yield Additional Percentage is 0.20%.

Agents:                            BMO Nesbitt Burns        Scotia Capital Inc.
                                          RBC Dominion Securities Inc.
                                          TD Securities Inc.
                                          CIBC World Markets Inc.
                                          HSBC Securities (Canada) Inc.
                                          National Bank Financial Inc.


Bearer Non-Interest Bearing
Notes:                                   Yes                    X   No
                                   -----                      -----

Registered Interest Bearing
Notes:                               X   Yes                        No
                                   -----                      -----

Interest Rate:                     5.65% per annum

Interest Payment Dates:            January 15 and July 15
                                   commencing January 15, 2004

DOCUMENTS INCORPORATED BY REFERENCE:

The following is a list of the documents which have been filed with the various
securities commissions in each of the provinces and territories of Canada and
which are specifically incorporated by reference in and form an integral part of
the short form base shelf prospectus dated November 20, 2002 as supplemented by
the prospectus supplement dated
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November 29, 2002 (collectively, the "MTN Prospectus") other than documents
already listed in the MTN Prospectus:

     (a)  Consolidated comparative audited financial statements of the
          Corporation as at and for the year ended December 31, 2002, the notes
          thereto, and the auditors' report thereon;

     (b)  Management's Discussion and Analysis of Financial Condition and
          Results of Operations of the Corporation as at and for the year ended
          December 31, 2002;

     (c)  Renewal Annual Information Form of the Corporation for the year ended
          December 31, 2002 dated February 25, 2003;

     (d)  Management Proxy Circular of the Corporation dated February 25, 2003
          relating to the annual and special meeting of shareholders held on
          April 25, 2003 (excluding the sections entitled "Composition of the
          Human Resources Committee", "Report on Executive Compensation",
          "Performance Graph" and "Corporate Governance");

     (e)  Consolidated comparative interim unaudited financial statements of the
          Corporation for the nine month period ended September 30, 2003;

     (f)  Management's Discussion and Analysis of Financial Condition and
          Results of Operations of the Corporation for the nine month period
          ended September 30, 2003; and

     (g)  Material change report of the Corporation dated May 23, 2003 relating
          to the plan of arrangement with TransCanada Corporation, establishing
          TransCanada Corporation as the parent company of the Corporation.

REDEMPTION PROVISIONS:

The Corporation shall be entitled to redeem the Medium Term Note Debentures
referred to herein (the "Debentures"), in whole at any time, or in part from
time to time, on not more than 60 and not less than 30 days' prior notice, at
the higher of the Canada Yield Price (as defined below) and par, together with
accrued and unpaid interest to the date fixed for redemption.

"Canada Yield Price" shall mean, in effect, a price equal to the price of the
Debentures calculated to provide a yield to maturity equal to the Government of
Canada Yield (as defined below) plus 0.20% on the business day preceding the
date of the resolution of the Corporation authorizing the redemption.
"Government of Canada Yield" on any date shall mean, in effect, the yield to
maturity on such date compounded semi-annually which a non-callable Government
of Canada Bond would carry if issued, in Canadian Dollars in Canada, at 100% of
its principal amount on such date with a term to maturity equal to the remaining
term to maturity of the Debentures. The Government of Canada Yield will be the
average of the yields determined by two major Canadian investment dealers
selected by the Corporation.