Attached files

file filename
EX-32.2 - EX-32.2 - TC PIPELINES LPa2234576zex-32_2.htm
EX-32.1 - EX-32.1 - TC PIPELINES LPa2234576zex-32_1.htm
EX-31.2 - EX-31.2 - TC PIPELINES LPa2234576zex-31_2.htm
EX-31.1 - EX-31.1 - TC PIPELINES LPa2234576zex-31_1.htm
EX-23.3 - EX-23.3 - TC PIPELINES LPa2234576zex-23_3.htm
EX-23.2 - EX-23.2 - TC PIPELINES LPa2234576zex-23_2.htm
EX-23.1 - EX-23.1 - TC PIPELINES LPa2234576zex-23_1.htm
EX-12.1 - EX-12.1 - TC PIPELINES LPa2234576zex-12_1.htm
10-K - 10-K - TC PIPELINES LPa2234576z10-k.htm

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Exhibit 21.1


SUBSIDIARIES OF THE REGISTRANT

1.
The Registrant holds a 98.9899 percent limited partner interest in TC GL Intermediate Limited Partnership, a Delaware limited partnership.

2.
Through its interest in TC GL Intermediate Limited Partnership, the Registrant holds a 46.45 percent general partner interest in Great Lakes Gas Transmission Limited Partnership, a Delaware limited partnership.

3.
The Registrant holds a 98.9899 percent limited partner interest in TC PipeLines Intermediate Limited Partnership, a Delaware limited partnership.

4.
Through its interest in TC PipeLines Intermediate Limited Partnership, the Registrant holds a 50 percent general partner interest in Northern Border Pipeline Company, a Texas general partnership.

5.
Through its interest in TC PipeLines Intermediate Limited Partnership, the Registrant wholly-owns Gas Transmission Northwest LLC, a Delaware limited liability company.

6.
Through its interest in TC PipeLines Intermediate Limited Partnership, the Registrant wholly-owns Bison Pipeline LLC, a Delaware limited liability company.

7.
Through its interest in TC PipeLines Intermediate Limited Partnership, the Registrant wholly-owns North Baja Pipeline, LLC, a Delaware limited liability company.

8.
The Registrant holds a 98.9899 percent limited partner interest in TC Tuscarora Intermediate Limited Partnership, a Delaware limited partnership.

9.
Through its interest in TC Tuscarora Intermediate Limited Partnership, the Registrant wholly-owns TC Pipelines Tuscarora LLC, a Delaware limited liability company.

10.
Through its interest in TC Tuscarora Intermediate Limited Partnership and TC Pipelines Tuscarora LLC, the Registrant wholly-owns Tuscarora Gas Transmission Company, a Nevada general partnership.

11.
Through its interest in TC PipeLines Intermediate Limited Partnership, the Registrant holds a 49.9 percent general partner interest in Portland Natural Gas Transmission System, a Maine general partnership.



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SUBSIDIARIES OF THE REGISTRANT