Market Wire: Donald Trump hits Canada with additional 50% tariffs

The Canadian dollar is tumbling after Donald Trump imposed additional duties of 50% on a broad range of Canadian goods, a sharp escalation of the trade conflict with Ottawa that threatens to damage the Canadian economy and add to the strain on an already vulnerable currency.

The president signed three proclamations this evening under Section 338 of the Tariff Act of 1930, a Depression-era provision that allows the White House to penalise countries it deems to be discriminating against American commerce. The measures take effect at one minute past midnight on August 19, giving importers a 30-day window before the levies bite.

Although the proclamations are framed around three grievances — Canadian treatment of US vehicles, alcoholic beverages and dairy — their reach is far wider. The 50% duty will fall on products ranging from wine to hockey sticks to cement, and, crucially, will apply regardless of whether goods qualify for tariff-free treatment under the USMCA. That removes a protection Canadian exporters have relied on throughout the dispute.

Some important categories are carved out. Energy, potash, fish, critical minerals and goods already covered by the administration's Section 232 national-security tariffs are exempt. The exclusion of energy—Canada's single largest export category—limits the headline macroeconomic blow considerably.

The economic damage will be concentrated in Canada's industrial heartlands: autos and parts in Ontario, aluminium in Quebec, and an agricultural sector already suffering from elevated uncertainty. Because the new duties override USMCA origin rules, even integrated cross-border supply chains that had been shielded now face the full charge, raising costs on both sides of the border and complicating the just-in-time manufacturing model on which much of continental production depends.

Running alongside the Section 338 action is a Section 232 aluminium proclamation that, while not aimed explicitly at Canada, could hit it hard. The measure directs the Commerce Department to set up an incentive scheme rewarding companies that build or refurbish domestic smelters, allowing approved firms to import primary aluminium at half the prevailing Section 232 rate in return for onshoring commitments. Canada is by far the largest foreign supplier of primary aluminium to the United States, with output concentrated in Quebec. A policy explicitly designed to reshore that capacity adds a longer-term structural headwind to the immediate tariff shock.

The three grievances are not without substance. Canada has since April 2025 levied a 25% tariff on US-made vehicles falling outside USMCA rules of origin, a scheme Washington says is applied to American cars alone and has contributed to a roughly 22% decline in US vehicle exports to Canada, with shipments from Mexico, Japan, South Korea and Germany rising to fill the gap. Provincial curbs on American alcoholic beverages have been more dramatic still: all but two provinces have halted the purchase or sale of US drinks, contributing to an 81% collapse in exports. On dairy, the White House pointed to quotas on American cheese it argued were tighter than those Canada extends to the European Union.

For the Canadian dollar, the balance of risks tilts lower. Although the energy carve-out should soften the terms-of-trade shock, tariffs of this magnitude threaten to widen the growth gap between the two economies at a moment when Canada can least afford it, strengthening the case for easier monetary policy from the Bank of Canada.

Much now hinges on Ottawa's response. Retaliation risks a deeper tit-for-tat spiral and further currency weakness. A move to the negotiating table would follow the path taken by the 18 partners the White House says have already struck deals, but might expose Prime Minister Mark Carney to blowback from voters. Canadian negotiators could hold out hope for another wholesale repudiation of the president’s tariff regime in US courts, but the path there could be winding and long.

Either way, the risk discount demanded by investors in Canadian assets is likely to persist until the trading relationship becomes clearer.

Information on the various actions can be found here: https://www.whitehouse.gov/news/