EXHIBIT 7

                          TRANSCANADA PIPELINES LIMITED

                              450 - 1st Street S.W.
                            Calgary, Alberta, Canada
                                     T2P 5H1

                    CERTIFICATION OF CHIEF FINANCIAL OFFICER
                      REGARDING PERIODIC REPORT CONTAINING
                              FINANCIAL STATEMENTS

I, Russell K. Girling, the Chief Financial Officer of TransCanada PipeLines
Limited (the "Company"), 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 Company's Quarterly Report as filed on Form 6-K for the
period ended June 30, 2003 with the Securities and Exchange Commission (the
"Report"), that:

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

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


                                        /s/ Russell K. Girling
                                        ---------------------------------------
                                        Russell K. Girling
                                        Chief Financial Officer
                                        July 30, 2003