WASHINGTON — Trade negotiations between the United States and Canada broke down Friday night, and at 12:01 a.m. Saturday the United States began collecting 50% tariffs on roughly $20 billion of Canadian goods, about 5% of Canada's exports. Reported categories include electronics, industrial machinery, dairy, steel, lumber, automobiles, alcohol, cement, and hockey equipment. Energy, potash, and critical minerals were carved out. The legal basis is unusual. The administration invoked Section 338 of the Tariff Act of 1930, a provision that, according to Axios, no president has used since it was enacted. That novelty makes a court challenge likely, and it comes after a February Supreme Court decision stripped the president of tariff authority under a different statute. Prime Minister Mark Carney said the United States introduced terms late in the process that were "uneconomic, unfair and undermined the net benefits for Canada," and accused Washington of trying to limit Canada's ability to negotiate independently with other countries. He called the tariffs a miscalculation and said Canada "will match those tariffs dollar for dollar to protect our workers and businesses." US Trade Representative Jamieson Greer countered that "Canada declined to finalise the trade deal under the terms agreed earlier this week." Trump had postponed the same tariffs on Tuesday, saying at the time that the two governments had a deal.
Background
US-Canada trade totaled $376 billion in the first half of 2026, roughly double US-China trade and second only to Mexico. The two economies are unusually integrated, particularly in automobiles, where components can cross the border several times before a finished vehicle is sold. A border tariff in that system is charged repeatedly along the same supply chain.
Why it matters: Tariffs are paid by the importer, not by the exporting country, so the first cost lands on American firms buying Canadian inputs. How much reaches consumers depends on how much of it those firms decide to absorb.
What to watch: September 8, when Canada's retaliatory tariffs on US steel, dairy, appliances, and agricultural machinery are scheduled to take effect, and any lawsuit testing Section 338.