Introduction Following its exit from the European Union, a key aspect of the United Kingdom's trade policy has been to conclude free trade agreements (FTAs) with other countries and trading blocs (for further details please see "Back to basics: free trade agreements"). To that end, the United Kingdom has been negotiating 'roll over' FTAs to replace the European Union ones. (1) This includes the most significant of the United Kingdom's FTAs, the Trade and Cooperation Agreement (TCA), which was concluded with the European Union on 24 December 2020. A clear benefit of an FTA is the ability for businesses to make use of 'preferential tariff treatment' (ie, reduced or zero tariffs and quotas) when shipping their products between parties to the FTA.