May 2025: the 25% auto-parts tariff lands, and CUSMA becomes the dividing line

Dated entry. This covers 31 May 2025 and has not been updated since. Tariff rules change constantly and some of this will have been superseded — check the official sources before acting on it.

On 3 May 2025 the United States brought its 25% tariff on automobile parts into force.

The detail that mattered for anyone tendering freight was the carve-out: CUSMA-compliant auto parts were exempt — but not automobile knock-down kits or parts compilations, which paid the full rate regardless of origin.

What it meant for freight: duty stopped depending on what a shipment was and started depending on whether its origin could be proven. Certificates of origin, produced on demand, became the difference between a load clearing and a load sitting.