TC PipeLines, LP Increases First Quarter Cash Distribution and Schedules Earnings Teleconference and Webcast

CALGARY, ALBERTA, Apr 17 (MARKET WIRE) --
TC PipeLines, LP (NASDAQ: TCLP) (the Partnership) today announced the
board of directors of TC PipeLines GP, Inc., its general partner, has
declared the Partnership's first quarter 2008 cash distribution in the
amount of US$0.70 per unit. This cash distribution represents a 5.3 per
cent increase from the fourth quarter 2007 distribution of $0.665 per
unit, and a 7.7 per cent increase from the first quarter 2007
distribution.

Since January 1, 2007 the Partnership's annualized cash distribution has
increased from $2.40 per unit to $2.80 per unit with this announcement.

The cash distribution is the 36th consecutive quarterly distribution paid
by the Partnership and represents the fourth increase in the past year.
This distribution is payable on May 15, 2008 to unitholders of record as
of April 30, 2008.

"We're pleased with the strong performance of our Northern Border and
Great Lakes pipelines, and with the completion of the Tuscarora expansion
project on April 1," said Russ Girling, chairman and chief executive
officer of TC PipeLines GP, Inc. "Our business strategy is working and we
want to share that success with our unitholders. Since the beginning of
2007 we have increased the cash distribution to our unitholders by 17 per
cent."

The Partnership will release its first quarter 2008 financial results on
Thursday, April 24, 2008. Analysts, members of the public, the media and
other interested parties are invited to participate in a teleconference
and audio webcast on Thursday, April 24, 2008 at 10:00 a.m. (Mountain)
and 12:00 p.m. (Eastern). Mark Zimmerman, president of the general
partner, will discuss the first quarter 2008 financial results and
general developments and issues concerning the Partnership. To
participate, please call (866) 225-0198. A replay of the conference call
will also be available two hours after the conclusion of the call and
until midnight, Thursday, May 1, 2008, by dialing (800) 408-3053, then
entering pass code 3258631.

A live webcast of the conference call will also be available through the
Partnership's website at www.tcpipelineslp.com. An audio replay of the
call will be maintained on the website.

TC PipeLines, LP is a publicly traded limited partnership. TC PipeLines,
LP has interests in more than 3,600 miles of federally regulated U.S.
interstate natural gas pipelines, including Great Lakes Gas Transmission
Limited Partnership (46.45 per cent ownership), Northern Border Pipeline
Company (50 per cent ownership) and Tuscarora Gas Transmission Company
(100 per cent ownership). Great Lakes is a 2,115-mile pipeline serving
markets in Minnesota, Wisconsin, Michigan and eastern Canada. The
1,249-mile Northern Border Pipeline transports natural gas from the
Montana-Saskatchewan border to markets in the midwestern United States.
Tuscarora owns a 240-mile pipeline system that transports natural gas
from Oregon where it interconnects to TransCanada's Gas Transmission
Northwest System. TC PipeLines, LP is managed by its general partner, TC
PipeLines GP, Inc., an indirect wholly owned subsidiary of TransCanada
Corporation. TC PipeLines GP, Inc., also holds common units of TC
PipeLines, LP. Common units of TC PipeLines, LP are quoted on the NASDAQ
Stock Market and trade under the symbol "TCLP." For more information
about TC PipeLines, LP, visit the Partnership's website at
www.tcpipelineslp.com.

Contacts:
TC PipeLines, LP
Media Inquiries
Shela Shapiro / Cecily Dobson
(403) 920-7859 or Toll Free: 1-800-608-7859

TC PipeLines, LP
Unitholder and Analyst Inquiries
Myles Dougan
1-877-290-2772
Email: investor_relations@tcpipelineslp.com
Website: www.tcpipelineslp.com

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