$19.8 billion in annual Canadian exports to the U.S. could be hit when Trump's 50% tariffs take effect on Aug. 19, economists say, threatening to trim Canada's growth by 0.2 to 0.3 percentage point in 2026 and 2027.
The duties cover goods from dairy and liquor to wood products and hockey sticks, while exempting energy, potash, fish and critical minerals after Washington let the 2020 USMCA lapse and reopened trade talks.
Experts said the threat may still be a negotiating tactic, but warned it could suppress investment and hiring and trigger layoffs at small and midsize exporters that depend on U.S. buyers.
Canadian premiers and industry groups said the plan would raise costs and disrupt production on both sides of the border, even as Carney and Trump agreed to intensify negotiations.