Thousands of holidaymakers have rushed back to the UK in a bid to avoid quarantine measures imposed on France, which came into force on Saturday.
The 14-day isolation requirement from 04:00 BST also applied to people arriving from the Netherlands, Monaco, Malta, Turks and Caicos, and Aruba.
Eurotunnel trains sold out on Friday and air travellers faced steep prices, but some ferries increased capacity.
France warned it would take “reciprocal measures”.
The Netherlands warned against all but essential travel to the UK once the restrictions came into force on Saturday, but it said it will not introduce reciprocal measures.
The countries were targeted for quarantine restrictions because their infections rates exceeded 20 cases per 100,000 people over seven days, Transport Secretary Grant Shapps said.
