Customs declaration

[1] Most countries require travellers to complete a customs declaration form when bringing notified goods (alcoholic drinks, tobacco products, animals, fresh food, plant material, seeds, soils, meats, and animal products) across international borders.

Posting items via international mail also requires the sending party to complete a customs declaration form.

Travellers have to declare everything they acquired abroad and possibly pay customs duty tax on goods.

Incoming passengers are required to declare for inspection all food, plant material and animal products on arrival in Australia.

Through agreements, the EU has customs unions with Andorra, San Marino, and Turkey respectively, with the exceptions of certain goods.

[35] Post Brexit, the Northern Ireland Protocol came into effect on 1 January 2021, which was subsequently revised under The Windsor Framework, a legal agreement between the European Union and the United Kingdom which adjusts the operation of the Northern Ireland Protocol.

HMRC explains that "CHIEF is a reliable and robust platform" but "its age means it can’t easily keep pace with new technology".