Section 338 Canada Tariffs: What Trump Just Changed

On 23 October 2026 President Trump signed a proclamation that changes which Canadian goods face the Section 338 tariffs. From 30 October, plywood sheets, some paper products, certain machinery and refrigeration equipment, and certain packing crates and boxes come off the list, while certain valves, carpets and waste products are added¹. The tariffs apply whether or not a good qualifies under USMCA, and they stack on top of Section 232 tariffs¹. The 50% rate dates from July. What changed this week is the list.

What Section 338 means for the Canada tariffs

Section 338 is part of the Tariff Act of 1930. It lets the President proclaim extra duties on a country's goods when that country discriminates against U.S. commerce. The extra duty may offset the disadvantage but cannot exceed 50 percent of the goods' value, and it takes effect 30 days after the proclamation³. If the discrimination continues, the same law lets the President bar the country's goods from entry altogether³. You can read the text at 19 U.S. Code 1338 (https://www.law.cornell.edu/uscode/text/19/1338).

Because it works through proclamations, the list can be edited the same way. The White House fact sheet (https://www.whitehouse.gov/fact-sheets/2026/10/fact-sheet-president-donald-j-trump-further-modifies-canadian-products-subject-to-tariffs-under-section-338/) for this week's change says Section 338 lets the President amend an earlier proclamation when the public interest requires it¹. That is why a tariff regime can be narrowed in one place and widened in another without a new law.

How the Canada tariffs began

Three proclamations signed on 20 July 2026 added a 50% tariff on many Canadian goods². The White House gave its reasons in July (https://www.whitehouse.gov/fact-sheets/2026/07/fact-sheet-president-donald-j-trump-imposes-additional-tariffs-on-canada/): Canadian car quotas and tariffs, provincial bans on U.S. alcohol and dairy tariff-rate quotas. Energy, potash, Section 232 products, fish and critical minerals were excluded². The October fact sheet says the scope was first announced on 20 July and modified on 8 September¹, so this week's edit is the latest of several.

Canada did not stand still. AP reports that Canada retaliated with tariffs of 15% to 50% on American products, matching the U.S. measures dollar for dollar⁴, and that in September Trump banned about $1 billion of Canadian imports, including alcoholic beverages, dairy and motorcycles⁴. The import-ban power sits in the same section of the 1930 law.

Why the list changed

The politics are in the open. AP reported that the move was seen as helping Senator Susan Collins of Maine, who is in a tight race. Collins said she asked trade negotiator Jamieson Greer and Commerce Secretary Howard Lutnick for relief, citing Maine blueberry growers who need Canadian harvesting boxes⁴. The White House gives a different frame: it says the action protects U.S. farmers, manufacturers and workers and restores reciprocity in trade¹.

The July fact sheet puts numbers on that case: U.S. motor vehicle exports to Canada fell about 22%, or $5.6 billion, and U.S. alcoholic beverage exports fell about 81%, or $582 million, in the periods it cites². These are the administration's own figures, and we have not been able to check the periods or how much of each fall is due to Canadian policy rather than other causes.

Who pays a tariff?

A tariff is a tax collected at the border. AP's report is plain on the legal point: U.S. importers, not foreign countries, pay the tariffs⁴. Who bears the cost in the end depends on the product. An importer can absorb it, raise prices, or push its supplier to cut theirs, and economists disagree about the mix. Households feel prices. In an AP-NORC poll of 2,140 U.S. adults taken 24 to 28 September, 65% said they blame Trump's policies more than outside factors for persistently high prices⁴.

What is still unknown

The fact sheet names product categories, not tariff codes. The annex to the proclamation decides which exact goods move, and importers will have to check it before 30 October. This piece uses the White House summary of the changes because the annex was not available when it was written. The fact sheet also does not state how much trade the changes cover.