UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): JULY 10, 2003 TC PIPELINES, LP (Exact name of registrant as specified in its charter) DELAWARE 000-26091 52-2135448 (State or other jurisdiction (Commission (I.R.S. Employer of incorporation) File Number) Identification No.) 110 TURNPIKE ROAD, SUITE 203 01581 WESTBOROUGH, MASSACHUSETTS (Zip Code) (Address of principal executive offices) (508) 871-7046 (Registrant's telephone number, including area code)

ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS. (c) Exhibits. 99.1 Press Release issued by Northern Border Pipeline Company on July 10, 2003. ITEM 9. REGULATION FD DISCLOSURE On July 10, 2003, Northern Border Pipeline Company issued a press release announcing that it has received commitments from several entities for transportation capacity at the maximum rate available under its tariff, the majority of which are for terms of one to two years, leaving approximately 11% of the total system capacity expiring prior to November 1, 2003. TC PipeLines, LP (the "Partnership") owns a 30% general partner interest in Northern Border Pipeline Company. A copy of the press release of Northern Border Pipeline Company is furnished as Exhibit 99.1. The information in Item 9 of this report is being furnished, not filed, pursuant to Regulation FD. Accordingly, the information in Item 9 of this report will not be incorporated by reference into any registration statement filed by the Partnership under the Securities Act of 1933, as amended, unless specifically identified therein as being incorporated therein by reference. The furnishing of the information in this report is not intended to, and does not, constitute a determination or admission by the Partnership, that the information in this report is material or complete, or that investors should consider this information before making an investment decision with respect to any security of the Partnership or any of its affiliates. - 2 -

SIGNATURES Pursuant to the requirements 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. TC PipeLines, LP By: TC PipeLines GP, Inc., its general partner Dated: July 10, 2003 By: /s/ THERESA JANG --------------------------------- Theresa Jang Controller - 3 -

EXHIBIT INDEX NUMBER EXHIBIT 99.1. Press Release issued by Northern Border Pipeline Company on July 10, 2003. - 4 -

[COMPANY LOGO OMITTED] NEWS 13710 FNB Parkway NORTHERN BORDER RELEASE Omaha, NE 68154-5200 PIPELINE COMPANY Northern Plains Natural Gas Company, Operator For Further Information Contact: Media Contact: Martha Sumner-Kenney (402) 492-3401 Investor Contact: Ellen Konsdorf (402) 492-7500 NORTHERN BORDER PIPELINE COMPANY ANNOUNCES SIGNIFICANT CAPACITY COMMITMENTS FOR IMMEDIATE RELEASE: THURSDAY, JULY 10, 2003 OMAHA - (NYSE: NBP; NASDAQ: TCLP) - Northern Border Pipeline Company announced today that it has received commitments from several entities for transportation capacity, leaving approximately 11% of the total system capacity expiring prior to November 1, 2003. These commitments are at the maximum rate available under Northern Border's tariff, the majority of which are for terms of one to two years, with a small amount of capacity extending up to ten years. "The success of the recontracting effort to date reinforces Northern Border's ongoing stability of revenue and cash flow," said Bill Cordes, chairman of the Northern Border Pipeline Management Committee. "We have been and remain confident in our ability to recontract our available capacity based on the favorable competitive position of the Northern Border system. Once again, the shippers have confirmed the value of holding pipeline capacity between Canadian supply areas and midwestern U.S. markets." Northern Border Pipeline Company is a general partnership that owns and operates a 1,249-mile interstate pipeline that transported approximately 20 percent of all Canadian gas imported into the United States in 2002. Northern Border Partners, L.P. (NYSE:NBP) owns a 70 percent general partner interest in Northern Border Pipeline Company. The remaining 30 percent general partner interest is owned by TC PipeLines, LP (Nasdaq: TCLP). THIS PRESS RELEASE INCLUDES FORWARD-LOOKING STATEMENTS WITHIN THE MEANING OF SECTION 27A OF THE SECURITIES ACT OF 1933 AND SECTION 21E OF THE SECURITIES EXCHANGE ACT OF 1934. ALTHOUGH THE COMPANY BELIEVES THAT ITS EXPECTATIONS ARE BASED ON REASONABLE ASSUMPTIONS, IT CAN GIVE NO ASSURANCE THAT SUCH EXPECTATIONS WILL BE ACHIEVED. IMPORTANT FACTORS THAT COULD CAUSE ACTUAL RESULTS TO DIFFER MATERIALLY FROM THOSE IN THE FORWARD-LOOKING STATEMENTS INCLUDE NATURAL GAS DEVELOPMENT IN THE WESTERN CANADIAN SEDIMENTARY BASIN; COMPETITIVE CONDITIONS IN THE OVERALL NATURAL GAS MARKETS; PERFORMANCE OF CONTRACTUAL OBLIGATIONS BY THE SHIPPERS; OUR ABILITY TO MARKET PIPELINE CAPACITY ON FAVORABLE TERMS; AND THE PRICE OF NATURAL GAS.