# Canada’s tariff changes: two dates to watch

https://geopax.app/blog/canada-tariff-changes-september-2026

By Andrew Liu

Published: 2026-09-21
Category: Research

September’s US tariff changes alter which Canadian products face additional duties. A separate set of import restrictions follows on September 29.

The September changes to US treatment of Canadian imports require two separate reviews: which products face an additional duty, and which products will face an import restriction. Those questions have different effective dates.

USITC published HTS Revision 19 on September 15, incorporating changes to the scope of Canadian products subject to additional duties. Here is what import teams should check as of September 21.

## The product list changed

The September 8 motor-vehicle-related proclamation adds the Canadian products in Part A of its Annex I to a 50% additional duty under Section 338. It removes the products in Part B from that additional duty. These changes took effect on September 15.

This is a change to a defined product list, not a 50% rate for every Canadian import. Match the product to the annex and the updated HTS provisions before changing its duty treatment. The White House describes the broader changes as removing products such as rock salt and cement and adding products such as ATVs and additional dairy products.

Revision 19 also incorporates a separate proclamation concerning Canadian alcoholic beverages. The relevant proclamation and its annex determine the scope for each product.

[USITC: HTS Revision 19](https://www.usitc.gov/2026_hts_revision_19)

[White House: September 8 scope changes](https://www.whitehouse.gov/presidential-actions/2026/09/modifying-the-scope-of-products-of-canada-subject-to-the-additional-duties-imposed-to-offset-canadian-discrimination-against-the-united-states-with-respect-to-motor-vehicles/)

## Two dates, different triggers

The September 15 duty-scope changes apply to covered goods entered for consumption, or withdrawn from warehouse for consumption, on or after 12:01 a.m. eastern time that day. A purchase order or departure date does not establish that entry date.

A separate September 8 proclamation excludes certain listed Canadian products from importation beginning at 12:01 a.m. eastern time on September 29. Its trigger is importation. This is an import restriction, not an exclusion that reduces a tariff bill.

Under that proclamation, covered products imported before September 29 but not yet entered for consumption or withdrawn from warehouse remain subject to the specified 50% additional duty. Teams need the actual import and entry dates to distinguish these cases.

[White House: September 29 import restrictions](https://www.whitehouse.gov/presidential-actions/2026/09/excluding-certain-canadian-products-from-importation-into-the-united-states-in-response-to-continued-discrimination-against-the-commerce-of-the-united-states-with-respect-to-motor-vehicles/)

## Check the other duties too

USMCA qualification does not, by itself, remove these Section 338 duties. The White House states that the tariffs apply to covered goods regardless of USMCA origin status and in addition to Section 232 tariffs.

For the same reason, removing a product from this Section 338 list does not establish that its total duty is zero. Our reading is that the review must still account for the base tariff and any other applicable measures. Treat each change as an update to the product’s full duty calculation.

[White House: Canada measures fact sheet](https://www.whitehouse.gov/fact-sheets/2026/09/fact-sheet-president-donald-j-trump-responds-to-canadas-retaliation/)

## Start with the affected products

We recommend a product-level review with two outputs: the duty treatment for affected entries and the admissibility position for upcoming imports. Keep those reviews separate so a cost estimate cannot be mistaken for permission to import.

Bring the product’s classification and origin together with its specifications, supplier records, and broker entry documents. Then add shipment timing and warehouse status. Assign an owner to each unresolved fact and retain the source behind each conclusion.

The hard part is often finding those records across an ERP, supplier emails, and broker files. Linking them gives the team a repeatable way to identify affected products and review the next change without rebuilding the same spreadsheet. Confirm the product-specific treatment with your customs broker before acting on it.