A comprehensive overview of the new rules for wine trading can be found on the UK government’s official website wine import and export summary page.
Overview
eAD
To ensure your consignments are not held up or detained you need to understand the documentation needed:
A commercial invoice is still needed to import wine from the EU but there is a change to the eAD (electronic administrative document) which will still be issued but not for the whole of the journey from mainland Europe into the UK. It will only apply to the transport from the production site to the European port of exit. Details can be found here on how to complete the eAD https://www.gov.uk/government/publications/excise-movement-control-system-how-to-complete-an-electronic-administrative-document/excise-movement-control-system-how-to-complete-an-electronic-administrative-document
EX-1
Imported wine from the EU will also require a standard export document (EX-1) it is a conventional form which confirms the goods are for export from the EU.
The EX-1 must accompany the goods to the customs office of exit at the EU external border. The customs office of exit will then confirm the exit of the goods from the customs territory of the Community. With this confirmation, the export procedure is completed.
It is important to note that both the EX-1 and eAD documents are closed upon arrival at the EU port of exit and so do not cover the transport on to the UK.
C88 Single Administrative Document (SAD)
To enable this next leg of the journey into the UK an import clearance document (C88) is needed to enable the wines to enter the country. With this document, the wine can be sent to a fully bonded tax warehouse, or be the duty paid against a deferment approval number. It is worth noting that if the UK warehouse is not a fully bonded one, then it is approved for suspended excise-only and two customs declarations are needed. In these cases, a C88 duty paid form must be issued that covers the UK global tariff (the replacement to the EU’s Common External Tariff commonly known as CCT) as well as a UK eAD with a movement guarantee to cover the full excise tax.