TRANSCANADA

TRANSCANADA

March 17, 2005 18:10 ET

TransCanada Prices TC PipeLines, LP Secondary Unit Offering


NEWS RELEASE TRANSMITTED BY CCNMatthews

FOR: TRANSCANADA

NYSE, TSX SYMBOL: TRP

MARCH 17, 2005 - 18:10 ET

TransCanada Prices TC PipeLines, LP Secondary Unit
Offering

CALGARY, ALBERTA--(CCNMatthews - March 17, 2005) - TransCanada
Corporation (TSX:TRP) (NYSE:TRP) (TransCanada) today announced it has
priced the previously announced secondary offering of 3,500,000 common
units of TC PipeLines, LP (the Partnership) owned by TransCanada
subsidiaries. The 3,500,000 common units have been priced at $37.04 US
per unit based on the closing price of the units on the Nasdaq National
Market on March 17, 2005. The Partnership will not receive any proceeds
from the sale of the common units offered. The underwriters have the
option to purchase up to 525,000 additional units on the same terms and
conditions to the extent more than 3,500,000 common units are sold in
the offering.

Assuming a sale of 3,500,000 common units, the net proceeds of this
offering of approximately $124 million US (approximately $149 million
CDN) will accrue to TransCanada and TransCanada expects to realize a net
gain of approximately $40 million US (approximately $48 million CDN)
after tax on the sale, which will be recorded in the first quarter of
this year. TransCanada intends to use the net proceeds from the sale to
assist in funding its 2005 capital requirements as well as for other
corporate purposes. The Partnership will not receive any of the proceeds
from the common units sold by TransCanada.

After the offering, subsidiaries of TransCanada will continue to own the
Partnership's general partner interest as well as approximately 12 per
cent of the Partnership's limited partner interest, assuming the
underwriters' option to purchase additional units is not exercised.

The offering is being led by Citigroup Global Markets Inc. and Lehman
Brothers Inc. and is expected to close March 23, 2005. In addition, UBS
Securities LLC, Goldman, Sachs & Co. and A.G. Edwards Inc. are
co-managing underwriters.

A copy of the final prospectus supplement and related base prospectus
for this offering can be obtained from Lehman Brothers Inc., c/o ADP
Financial Services, Integrated Distribution Services, 1155 Long Island
Avenue, Edgewood, NY 11717, email: monica_castillo@adp.com, or from
Citigroup Global Markets Inc., 140 58th Street, Brooklyn, NY 11220. Any
direct requests to Citigroup should be made to the Prospectus Dept by
telephone 718-765-6732 or by fax at 718-765-6734.

This news release does not constitute an offer to sell or a solicitation
of an offer to buy the limited partnership interests described herein,
nor shall there be any sale of these limited partnership interests in
any state or jurisdiction in which such an offer, solicitation or sale
would be unlawful prior to registration or qualification under the
securities laws of any such jurisdiction. The offering may be made only
by means of a prospectus and related prospectus supplement.

TransCanada is a leading North American energy company. TransCanada is
focused on natural gas transmission and power services with employees
who are expert in these businesses. TransCanada's network of
approximately 41,000 kilometres (25,600 miles) of pipeline transports
the majority of Western Canada's natural gas production to the fastest
growing markets in Canada and the United States. TransCanada owns,
controls or is constructing more than 5,100 megawatts of power
generation - enough to meet the electricity needs of about 5.1 million
average households. The Company's common shares trade under the symbol
TRP on the Toronto and New York stock exchanges. Visit TransCanada on
the Internet at www.transcanada.com for more information.

FORWARD-LOOKING INFORMATION

Certain information in this news release is forward-looking and is
subject to important risks and uncertainties. The results or events
predicted in this information may differ from actual results or events.
Factors which could cause actual results or events to differ materially
from current expectations include, among other things, the ability of
TransCanada to successfully implement its strategic initiatives and
whether such strategic initiatives will yield the expected benefits, the
availability and price of energy commodities, regulatory decisions,
competitive factors in the pipeline and power industry sectors, and the
current economic conditions in North America. For additional information
on these and other factors, see the reports filed by TransCanada with
Canadian securities regulators and with the United States Securities and
Exchange Commission. TransCanada disclaims any intention or obligation
to update or revise any forward-looking statements, whether as a result
of new information, future events or otherwise.

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Contact Information

  • FOR FURTHER INFORMATION PLEASE CONTACT:
    TransCanada
    Media Inquiries
    Kurt Kadatz/Hejdi Feick
    (403) 920-7859 or (800) 608-7859
    or
    Investor & Analyst Inquiries
    David Moneta
    (403) 920-7911
    Website: www.transcanada.com