De-escalation on one front: effective September 1, 2026, Canada removed its own retaliatory tariffs on US goods that qualify under CUSMA (announced by PM Carney on August 22). Canada is keeping retaliatory duties on US steel, aluminum, and non-CUSMA vehicles in place — and its separate, larger $27.6B counter-tariff list responding to this Section 338 tariff is unaffected and still takes effect September 8, 2026. What's still tariffed vs. what Canada just removed →
Canada is now the latest target of a new and unusual tariff tool. On July 20, 2026, President Trump signed three separate proclamations invoking Section 338 of the Tariff Act of 1930 — a rarely used, decades-old provision that lets the President impose duties of up to 50% on goods from a country found to discriminate against US commerce, and one no president had used this way before. The administration cited Canadian trade practices around automobiles, alcohol (provincial liquor-board restrictions on US products), and dairy (Canada's supply-management tariff-rate quota system) as the discriminatory conduct. The tariff was originally due to take effect 12:01 a.m. ET August 19, 2026, then got a three-day reprieve while the two countries worked toward a broader deal. That deal did not materialize: talks broke down, Prime Minister Mark Carney suspended negotiations and recalled Canada's negotiating team, and the 50% tariff took effect as scheduled at 12:01 a.m. ET Saturday, August 22, 2026. Carney said Canada would match the US tariffs dollar for dollar. This guide covers what's covered, what changed today, and the one detail that matters most for anyone importing from Canada: USMCA doesn't help here.
What Changed and When
President Trump signed three Section 338 proclamations on July 20, 2026, each imposing a 50% tariff on a different set of Canadian goods tied to disputes over motor vehicles, alcohol, and dairy. Section 338 of the Tariff Act of 1930 allows the President to impose additional duties of up to 50% on goods from any country found to discriminate against US commerce — it had never been invoked this way before, which is why trade press called it the administration's 'nuclear option.' The tariffs were set to take effect 30 days after signing, 12:01 a.m. ET on August 19, 2026, but hours before that deadline the administration paused it for three days, through the end of the day Friday, August 21, citing progress toward a broader trade deal. That deal did not come together: a further round of talks in Washington broke down, Prime Minister Mark Carney suspended negotiations and recalled Canada's negotiating team, and the 50% tariff took effect as originally scheduled once the pause expired — 12:01 a.m. ET Saturday, August 22, 2026. Carney announced Canada would retaliate with matching dollar-for-dollar tariffs on US goods, and on August 25, 2026 Canada's Department of Finance published the full retaliation list — see the section below for what's covered.
What's Covered
Reporting on the proclamations describes coverage spanning motor vehicles, wine and other alcohol, dairy products (including milk and cream), cement, furniture, fishing rods, seeds, clothing, wigs, and hockey sticks and other hockey equipment — three distinct proclamations covering different product groups rather than one blanket list. As with any new proclamation, the binding text is the specific HTS subheadings named in each Federal Register notice; check your product's HTS code against the official notices or with a licensed customs broker before assuming coverage either way.
Advertisement
What's Excluded
The Section 338 tariffs do not apply to energy products, potash, goods already subject to Section 232 tariffs (steel, aluminum, copper, autos already at the Section 232 rate), fish, or critical minerals. Canada's major resource exports to the US — oil, gas, potash, and critical minerals — are carved out of this particular action.
The USMCA Catch
This is the detail that is catching a lot of importers off guard now that the tariff is live: the Section 338 tariffs apply to covered goods regardless of whether they qualify for USMCA preferential treatment. Under the Section 122 and Section 232 regimes, USMCA-qualifying Canadian goods have generally been shielded or treated favorably. Section 338 works differently — it targets specific goods as a retaliatory response to specific Canadian policies, and a valid USMCA certificate of origin does not exempt a covered product from it. If you import Canadian autos, alcohol, dairy, or the other named categories, existing USMCA compliance does not protect you from this tariff.
The August 19-21 Pause, and Why It Failed
Hours before the tariff was originally due to take effect, President Trump announced a three-day pause, saying the US and Canada had reached the outline of a broader deal covering market access, economic security commitments, and digital trade, with final documents still being worked out. Prime Minister Mark Carney confirmed the postponement ran through the end of the day Friday, August 21. Trade officials held further rounds of talks in Washington through that Wednesday and Thursday, and reporting described the two sides as close on a package that would have cut Canada's existing Section 232 steel/aluminum and auto tariffs. But by the pause deadline, Carney said last-minute changes to the US proposed terms were 'unfair, uneconomic, and called into question the reliability of any deal,' suspended negotiations, and recalled Canada's negotiating team to Ottawa. No proclamation was withdrawn or amended during the pause, so once it lapsed the original 50% duty took effect automatically at 12:01 a.m. ET August 22, 2026.
Canada's Response: Dollar-for-Dollar Retaliation
Carney said Canada would match the new US tariffs 'dollar for dollar' on US goods to protect Canadian workers, farmers, and businesses. On August 25, 2026, Canada's Department of Finance published the complete list. Finance Minister François-Philippe Champagne confirmed counter-tariffs of 15%, 25%, or 50% — each product rate matched to the corresponding US Section 338 or Section 232 rate — covering roughly 700 US product lines worth $27.6 billion (up from the roughly $20 billion originally floated). US steel and aluminum products previously at 25% move to 50%; appliances, dairy (including cheese), and certain steel/aluminum derivatives sit at 25%; a smaller category — electric equipment and tools — gets 15%. Goods already in transit to Canada on the effective date are exempt. Champagne also announced a multi-billion-dollar support package for Canadian workers and businesses affected by the trade fight. The counter-tariffs take effect 12:01 a.m. September 8, 2026 — the Tuesday after Labor Day. Provincial leaders, including Ontario Premier Doug Ford, backed Carney's response. See Canada's official product list at canada.ca for the full HTS-line detail. Separately, and on a different track: on August 22, 2026 Carney also announced Canada would remove its own retaliatory tariffs on US goods that qualify under CUSMA, effective September 1, 2026 — Canada is easing older CUSMA-related duties even as it prepares this new, larger non-CUSMA counter-tariff list. Canada is keeping retaliatory tariffs on US steel, aluminum, and non-CUSMA-compliant vehicles in place.
What to Do Now That the Tariff Is Live
- Check whether your specific HTS code falls under one of the three proclamations — don't rely on a product-category summary, confirm against the official Federal Register notices or with a licensed customs broker.
- Don't assume USMCA protects you. A valid certificate of origin does not exempt covered goods from this tariff.
- Re-run landed cost now. The 50% duty is live as of 12:01 a.m. ET August 22, 2026 — update quotes and budgets accordingly rather than treating it as still paused.
- If you also export to Canada, check the published retaliation list. Countermeasures start September 8, 2026 — Canada's Department of Finance published the full ~700-line product list on August 25, 2026, with rates of 15%, 25%, or 50% depending on the product.
Key Takeaway
Section 338 is a new and unfamiliar tool in the 2026 tariff landscape, and its USMCA-blind design is the part importers are most likely to miss now that it's live. Trade talks collapsed, Canada suspended negotiations and pledged dollar-for-dollar retaliation, and the 50% tariff took effect at 12:01 a.m. ET August 22, 2026. If you import Canadian autos, alcohol, dairy, furniture, or the other named categories, confirm your HTS exposure and re-run your landed cost now — this is no longer a pending risk.
Calculate Your Import Duty
Get an instant estimate for your specific product, country, and shipment value.
Open the US Import Duty CalculatorAdvertisement
