Canada's dollar-for-dollar retaliation against US Section 338 duties entered force at 12:01 a.m. September 8, the effective date Finance Minister Francois-Philippe Champagne published on August 25.
The US 50 percent additional tariff on selected Canadian goods entered its eighteenth day on Tuesday, continuing the August 22 effective cycle.
Finance Canada's August 25 announcement and August 26 revised counter-tariff table apply to roughly C$27.6 billion of US-origin imports at rates of 15, 25, or 50 percent matching corresponding US Section 338 and Section 232 lines.
Steel and aluminum products remain at 50 percent, doubling prior 25 percent surtaxes. Dairy, appliances, pulp and paper, electronics, furniture, and clothing stay in scope.
Goods already in transit to Canada on the effective date are exempt, a screening detail importers worked through ahead of Tuesday morning.
Elemental sulfur, HS 2503, remains absent from both the US covered lists and Canada's published September 8 retaliation table.
Canada's customs tariff schedule continues to list sulfur of all kinds, other than sublimed, precipitated, or colloidal sulfur, at free under heading 2503.00.00.
Energy, potash, fish, and critical minerals also stay outside the exchange on open reporting, though fish and seafood were removed from Canada's retaliation side in the revised August 26 list.
Canada remains the dominant US import source for recovered sulfur per USGS import-source tables, so a tariff-free HS 2503 lane keeps the cross-border molten and solid corridor commercially open.
SMM's July Canadian export print showed 444,100 tonnes for the month with 172,200 tonnes to the United States, underscoring how much of the Alberta book still clears south as well as west through the Vancouver stem.
Pacific loadings have been the swing-supplier answer while Middle East seaborne stays impaired. Alberta forming plants and British Columbia terminals face no new duty layer on sulfur even as steel and appliances enter the retaliation cycle.
Open legal commentary from Blakes and Gowling WLG confirmed the September 8 measures do not stack on top of existing counter-tariffs in most sectors, though steel and aluminum surtaxes rose from 25 to 50 percent to match US rates.
Desk read: Ottawa's published retaliation lines are now live. HS 2503 remains off both schedules, keeping the Alberta-to-US molten corridor and the Vancouver stem commercially open on duty treatment.