US Supreme Court Ruling and New Global Tariff: What UK Importers and Exporters Need to Know

24 February 2026

 

Recent developments in US trade policy have introduced both relief and renewed uncertainty for UK businesses trading with the United States.

The US Supreme Court has ruled that the President does not have authority under the International Emergency Economic Powers Act (IEEPA) to impose broad global tariffs during peacetime. As a result, a number of tariffs previously implemented under that authority have been invalidated. For UK exporters, this could potentially reduce duty exposure on affected product lines and may open the door to refund claims where IEEPA-based tariffs were paid.

However, the relief may be short-lived. In response to the ruling, the US administration has invoked Section 122 of the Trade Act of 1974, introducing a temporary global import surcharge.

Unlike IEEPA, Section 122 explicitly allows the President to impose a short-term tariff of up to 15% for a period of 150 days to address balance-of-payments concerns. The official proclamation has set the current surcharge at 10% ad valorem, effective for the permitted temporary period. While 15% is the legal maximum under Section 122, any increase above 10% would require a further formal proclamation and publication in the Federal Register.

For UK exporters, this means:

  • UK-origin goods entering the US may now be subject to a temporary 10% global surcharge, unless specifically exempted.
  • Pricing models, landed cost calculations and US distribution contracts may need immediate review.
  • Supply chains relying on predictable tariff treatment could face short-term disruption.

For UK importers sourcing via the US, there may be knock-on cost increases where US-based suppliers pass on higher import costs linked to the surcharge.

Importantly, other US tariff regimes — including Section 232 (national security) and Section 301 (unfair trade practices) — remain fully in force and are unaffected by the Supreme Court ruling.

What UK Businesses Should Do Now

  • Review product classifications and confirm whether goods are impacted by the Section 122 surcharge.
  • Reassess US pricing strategies and margin exposure.
  • Monitor official US publications for clarification on exemptions, extensions or any increase toward the 15% ceiling.
  • Seek specialist customs advice if IEEPA-related refund opportunities may apply.

While the Supreme Court ruling removes one layer of tariff authority, the introduction of a temporary 10% global surcharge means UK businesses must remain vigilant. The US trade environment continues to evolve rapidly, and proactive tariff monitoring remains essential.

 

By Carla Assunção - Chamber International.

 

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