Canada's retaliatory surtaxes on U.S. goods take effect on 8 September

Canada begins collecting new retaliatory surtaxes on U.S. goods on 8 September. The list covers more than 700 tariff lines and about C$27.6 billion ($19.9 billion) of annual imports, the same order of magnitude as the Canadian exports hit by President Donald Trump's latest 50 percent duties. Rates are 15, 25 or 50 percent and apply only to goods originating in the United States.

Prime Minister Mark Carney promised a dollar-for-dollar response after three days of talks failed in late August. Finance Minister François-Philippe Champagne published the lines a few days later. Steel and aluminum surtaxes rise to 50 percent on most items. Motor vehicles stay at 25 percent, with the existing system that lets firms building cars in Canada bring in a quota of U.S.-built cars free of that extra tax. A smaller set of lines, including some air-conditioning units and tool parts, take 15 percent.

The rest of the list is deliberately wide. It includes fish and cheese, smartphones, appliances, agricultural equipment, pulp and paper, cosmetics, wood products, outdoor gear, railway locomotives, steel bridges, aluminium foil, hockey sticks, ornamental fish, toilet paper and smoked lobster. Many lines mirror products Washington taxed in the August 22 package, which landed on about $20 billion of Canadian goods from honey to hockey equipment and did not spare CUSMA-originating items.

The United States had already been collecting a 25 percent tariff on automobiles, a central Canadian export, for about 18 months, and 50 percent sectoral duties on steel and aluminium. The August round was the step that ended the talks. Carney said Canada had been attacked and would protect workers, farmers, families and businesses. Champagne said Canadians remained "masters of our own home."

Importers who cleared goods before 8 September pay the old rate. Goods that enter from Monday morning pay the new one. Customs brokers will spend the week matching 10-digit codes to the finance department list. Errors will show up as unpaid surtax, not as a political argument.

CUSMA still covers most of the two-way flow. The fight is now about the slice that sits outside that shelter and about the extra taxes piled on top of the treaty. A 50 percent surtax on U.S. steel coming into Canada, stacked on a 50 percent U.S. tax on Canadian steel going south, is a closed loop that raises prices on both sides of the Detroit-Windsor crossing.

No new negotiating date was attached to the 8 September start. The surtaxes stay until Ottawa rescinds them. That is a cabinet instrument, not an automatic sunset. Anyone waiting for a quiet rollback on day one will not get one.