Trump’s Trade Move Could Increase Costs for Many Online Goods

President Trump’s decision to impose hefty tariffs on Canada, Mexico and China included a little-noticed but significant change to how online purchases will be taxed when they enter the United States.

One provision of Mr. Trump’s executive order will increase costs for more than 80 percent of U.S. e-commerce imports. The decision could shift the landscape for online sales from Chinese vendors like Shein and Temu that have swiftly expanded their market share by sending cheap goods into the United States.

The president’s order erased a workaround that many companies have taken advantage of in recent years, particularly since Mr. Trump imposed tariffs on Chinese products in his first term. The provision, known as the de minimis exception, allowed certain products that were sent directly to consumers from online platforms to come into the United States without facing tariffs, a huge tax advantage.

This obscure provision of trade law underpins major business models. Shein, Temu and many sellers on Amazon have used the de minimis exemption to bypass tariffs. The exemption allows packages to be shipped from other countries without paying tariffs, as long as the shipments do not exceed $800 per recipient per day.

But critics say the de minimis measure has also helped fuel an American drug crisis. Importers who use de minimis do not have to provide as much information to U.S. Customs and Border Protection as they do with other packages, for ease of processing. That means drugs and the precursors used to make them could be more easily shipped into the United States without the government catching them.

De minimis stems from a century-old trade law that was originally intended for shipments that would be too trivial to merit the