National Bank of Canada assessed the potential impact of 10% U.S. energy tariffs on Enbridge (ENB.TO), TC Energy (TRP.TO), South Bow (SOBO.TO), Pembina Pipeline (PPL.TO) and Keyera (KEY.TO) in a note published over the weekend.

The bank said the Enbridge Mainline currently operates under a tolling settlement agreement through 2028, providing downside protection in the event of material supply/demand disruptions or unexpected operating cost pressure.

"We do not see significant curtailment risk under a 10% tariff, and as such would look to add to a position in ENB on any tariff-related stock price weakness <$60," the bank said.

The bank has a sector-perform rating on Enbridge shares and a $63.00 price target.

For TC Energy, National Bank said the company's main natural-gas export pipelines operate under a regulated framework or take-or-pay negotiated contracts with an average duration into early next decade.

As such, cash flows from these assets are not exposed to commodity price or volumetric risk, protecting financial performance over the medium term.

The bank maintained its outperform rating and $74 price target on TC Energy.

Meanwhile, the bank said tariffs may dampen South Bow's ability to maximize utilization and profitability of the Keystone pipeline, while noting that its estimates do not currently assume a material uptick in marketing contributions from the relatively muted contributions experienced in 2024/2025.

National Bank maintained its sector-perform rating and US$24.00 price target on the company's shares.

Pembina's Alliance Pipeline is currently undergoing regulatory review of its tolls to determine whether the current tolling methodology is justified, the bank said.

The bank expects a 5%-10% pinch in Alliance cash flows as a result of the tolling regulatory review but does not see the 10% tariff as a material risk to its longer-term contracted profile.

The bank kept its sector-perform rating and $58 target on Pembina's shares.

Although Keyera's G&P and Liquids Infrastructure segments are largely insulated from U.S. tariffs, the bank expects downward pressure on the company's Marketing contributions until tariffs are lifted.

Keyera's sector-perform rating and $41 price target was also reiterated.