In a dramatic escalation of US-Canada trade tensions, President Trump has signed three proclamations imposing 50% tariffs on Canadian goods under Section 338 of the Tariff Act of 1930. The President cited discriminatory treatment of U.S. goods by Canada as the basis for the action.
Legal Basis: Section 338
Section 338 of the Tariff Act of 1930 authorizes the President to impose additional duties of up to 50% on goods from countries that discriminate against U.S. commerce. Unlike Section 301 (which targets unfair trade practices) or Section 232 (which addresses national security), Section 338 specifically targets discriminatory tariff and trade treatment.
The use of Section 338 is historically rare and represents a significant escalation in the administration's trade policy toolkit. The three proclamations collectively cover a broad range of Canadian goods.
Impact on Importers
- Doubled tariff rates: Importers of Canadian goods face tariff rates up to 50%, effectively doubling the cost of many Canadian imports.
- HS code classification critical: Proper HS code classification is essential to determine which goods are covered by the proclamations and to calculate the correct duty obligations.
- Supply chain restructuring: Companies with heavy reliance on Canadian suppliers may need to evaluate alternative sourcing strategies.
- CUSMA/USMCA implications: The relationship between these new tariffs and existing CUSMA/USMCA commitments remains an area of legal uncertainty.
How Prime TMS Helps
Our HS Code Verification module helps identify affected product classifications, ensuring importers correctly classify their goods and calculate duty obligations. With over 18,000 HS code entries in our database, our TM Search Engine provides comprehensive coverage for classification verification.
Primary Source
White House Presidential Proclamations — Section 338 Tariff Actions on Canadian Goods, July 2026.