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-21.1 - EX-21.1 - TC PIPELINES LPa2234576zex-21_1.htm
10-K - 10-K - TC PIPELINES LPa2234576z10-k.htm

QuickLinks -- Click here to rapidly navigate through this document


Exhibit 12.1


COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

December 31 (millions of dollars)   2017   2016(a)   2015(a)   2014(a)   2013(a)(b)    

Earnings                        
  Net income before adjustment for income from equity investees   139   166   160   153   154    
  Fixed charges   84   73   68   62   57    
  Distributed income (loss) of equity investees(c)   124   97   (102 ) 88   67    
  Non-controlling interests of subsidiaries that have not incurred fixed charges         (10 ) (14 )  

Total Earnings   347   336   126   293   264    

Fixed Charges

 

 

 

 

 

 

 

 

 

 

 

 
  Interest expensed and capitalized   83   69   64   56   50    
  Amortization of other assets   1   4   4   6   7    

Total Fixed Charges   84   73   68   62   57    

Ratio of Earnings/Fixed Charges

 

4.13X

 

4.60X

 

1.85x

 

4.73x

 

4.63x

 

 
(a)
Recast information to consolidate PNGTS for all periods presented as a result of an additional 11.81 percent in PNGTS that was acquired from a subsidiary of TransCanada on June 1, 2017. Prior to this transaction, the Partnership owned a 49.9 percent interest in PNGTS that was acquired from TransCanada on January 1, 2016. Please read Note 2 – Significant Accounting Policies – Basis of Presentation section of the Notes to the Consolidated Financial Statements included in Part IV,Item 15. "Exhibits and Financial Statement Schedules".

(b)
Recast information to consolidate GTN and Bison for all periods presented as a result of additional 45 percent membership interests in each of GTN and Bison that were acquired from subsidiaries of TransCanada in 2013 resulting in a 70 percent ownership in each. Please read Note 2, Significant Accounting Policies- Basis of Presentation section of the Notes to the Consolidated Financial Statements included in Part IV,Item 15. "Exhibits and Financial Statement Schedules".

(c)
Distributed income of equity investees for 2015 includes $199 million impairment charge on our Investment in Great Lakes. Please read Note 5-Equity Investments, Notes to the Consolidated Financial Statements included in Part IV, Item 15. "Exhibits and Financial Statement Schedules".



QuickLinks

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES