U.S. Section 338 Tariffs: 50% Duties on Canadian Auto Imports Start Aug. 19

The White House issued a Section 338 proclamation on July 20, 2026 that sets a new 50% additional ad valorem duty on certain products of Canada as set forth in Annex II, scheduled to begin at 12:01 a.m. ET on Aug. 19, 2026.

What changed on July 20

Under the Tariff Act of 1930, the proclamation imposes an additional 50% duty on the covered Canadian products listed in Annex II. The administration says the action is meant to offset what it describes as Canada’s discriminatory tariff treatment of U.S. motor-vehicle commerce.

Why the administration is using “Section 338”

The proclamation cites Section 338, which is used when the United States determines a country is imposing unequal or discriminatory charges on U.S. commerce. A parallel USTR statement echoes that rationale for the Section 338 tariff approach.

Key dates—and what the effective time means

The proclamation was issued July 20, 2026. The new duty takes effect for goods entered for consumption, or withdrawn from warehouse for consumption, on or after 12:01 a.m. ET on Aug. 19, 2026.

That effective-time framing matters because costs tied to shipments already in the pipeline may not show up immediately in retail pricing—depending on when goods are formally entered for consumption or withdrawn from warehouse.

What goods are covered (and what’s not)

Readers don’t have to guess broad categories based on the headline. Coverage is determined by the proclamation’s Annex II list and how covered products are classified at import.

Why this matters for auto shoppers (timing over instant sticker shock)

The proclamation directs U.S. Customs and Border Protection to implement the duties, and the added duty applies to covered imports under the effective-time rules starting Aug. 19. The practical question for drivers and shoppers is how quickly importers’ higher landed costs flow into dealer inventory and showroom pricing.

What to watch next before Aug. 19

• CBP implementation steps (rules/guidance) that clarify how entries are handled for covered products.
• Any official updates that signal changes to annex coverage, classifications, or timing before the effective moment.
• Dealer inventory refresh patterns after Aug. 19, which can affect when any higher costs become visible on retail vehicles.

If you’re shopping for a vehicle in late August, the most actionable takeaway is to treat Aug. 19 as the point where covered import entries begin carrying the added duty—not necessarily the moment when prices jump everywhere the same day.

Sources

• White House — Section 338 motor-vehicles proclamation (July 20, 2026)
• USTR — Ambassador Greer statement on Section 338 tariffs (Canada; July 2026)
• AP News — Reporting on the new 50% tariffs and the autos-related Canada dispute