Background: 

The US implemented Section 122 of the US Trade Act of 1974 (19 U.S.C. § 2132), providing for a 10% duty on UK-supplied goods (with some exemptions) for a limited period of 150 days.   

This period ended on 24^th July, 2026.  Implementation of Section 301 Tariff measures was updated and came into force on the 14^th August. 

Although these tariff measures were broadly aimed at Chinese-origin goods, they are in addition to the Most Favoured Nation duty rates applicable to imports into the US, meaning that UK goods would be captured in the additional import duties as well as the MFN rate. 

Example: MFN duty rate of 5% against the US tariff code, plus an additional Section 301 duty of 10%.

The use of Section 232 of the Trade Expansion Act of 1962, intended to protect the US from imports that could impact national security, has already increased tariffs on specific UK goods imported into the US, primarily steel, aluminium, and copper. 

These duty rates remain in place and will be in addition to Section 301 duties applicable from August 14^th.

Following the introduction of new Section 301 tariffs by the United States, HMRC has updated the GOV.uk guidance on UK trade negotiations with the US.UK guidance on UK trade negotiations with the US.UK guidance.

The UK's trade negotiations with the US - GOV.UK

It has been updated to reflect the status of UK-origin products being imported into the US.

This follows the removal of the Section 122 tariffs, which the United States implemented for UK-origin products at a duty rate of 10%. The Section 122 tariffs were only valid for 150 days. The 150 days ended on 24 July 2026, when these tariffs were removed, and Section 301 was subsequently introduced.

The Section 301 tariffs are an additional 10% duty, which has also been applied to UK-origin products alongside any MFN (Most Favoured Nation) Rate that already applies. For example, a product with an MFN rate of 5% and 10% Section 301 duties would have a total payable duty rate of 15%. (5% + 10%)

What are Section 301 tariffs?

Section 301 tariffs follow the USTR investigation into the United Kingdom, which found that the UK failed to impose and enforce a forced labour prohibition. Because of this failure, the USTR determined that there was an unreasonable burden and restriction on United States commerce.

The investigation covered 60 countries. For the United Kingdom, this would be an additional 10% duty.

Federal Register: Actions by the United States in the Investigations Under Section 301 of the Trade Act of 1974 of the Acts, Policies, and Practices of 60 Economies Related to the Failure of Each Economy To Impose and Effectively Enforce a Prohibition on the Importation of Goods Produced With Forced Labor

The introduction of the section 301 tariffs does not remove any current section 232 tariffs. Further Adjusting the Tariff Regimes for Imports of Aluminum, Steel, and Copper into the United States – The White House

Section 232 duties cover products such as aluminium and steel, as well as derivative products which are captured under the

Section 232 duty regime but are not solely aluminium or steel.

For those products, you will still need to know the product content and country of smelting so the correct duties are allocated at the point of import into the US.

Further exemptions to Section 301 tariffs include civil aircraft and parts, as shown in U.S. Note 2(aa)(iv) to Subchapter III of Chapter 99 of the HTSUS.

Other exemptions include information material such as newspapers and carrying media, agricultural products, pharmaceuticals, some minerals, as well as copper, which can be found within Annex II - https://www.federalregister.gov/d/2026-15181

Further exempted products from Section 301 from certain countries can also be found within Annex I - https://www.federalregister.gov/d/2026-15181

Does the introduction of Section 301 tariffs affect you?

Overall, for UK exporters of UK-origin goods, potentially not, although we have seen the removal of the temporary 150-day Section 122 10% tariff and the introduction of Section 301 tariffs at 10%. Therefore, the duty rate has likely not changed.

What we really need to consider is staying vigilant and aware of potential changes; on 22 August 2026, the US introduced Section 338 against certain goods of Canadian origin at a duty rate of 50%.

How would that, for example, affect our supply chains? Would that impact us as a UK exporter? The US tariff regime has been very fluid since the introduction of the first reciprocal duties on 5 April 2025.

Where can I find out the duty rate for my product?

You can use the Check how to export pages to determine what the current rate of duty is for your product into the United States.

This requires the commodity code used at the point of import into the USA.

Check how to export goods - GOV.UK