EXHIBIT 32.1

                                  CERTIFICATION

     I, Ronald J. Turner, President and Chief Executive Officer of TC PipeLines
GP, Inc., the general partner of TC PipeLines, LP (the Partnership), in
compliance with 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of
the Sarbanes-Oxley Act of 2002 hereby certify in connection with the
Partnership's Quarterly Report on Form 10-Q for the period ended June 30, 2003
as filed with the Securities and Exchange Commission (the Report), that:

     o    the Report fully complies with the requirements of Section 13(a) or
          15(d) of the Securities Exchange Act of 1934; and

     o    the information contained in the Report fairly presents, in all
          material respects, the financial condition and results of operations
          of the Partnership.

Dated: August 14, 2003               /s/ Ronald J. Turner
                                    --------------------------------------------
                                    Ronald J. Turner
                                    President and Chief Executive Officer
                                    TC PipeLines GP, Inc., as general partner