Passengers travelling to the country will have to quarantine for the two week period unless they can show proof of having had two doses of a Covid-19 vaccine at least two weeks prior to arriving.
The new rules come into effect today (Monday June 28) and last until at least July 11 – they do not impact under 12-year-olds.
The law does not apply in Madeira, which has been moved back to the UK’s green list.
From 17 May, Portugal was on the UK’s ‘green list' and was a quarantine-free destination for holidaymakers.
But it was removed on 3 June over concern for a “Nepal mutation of the so-called Indian variant”, and British travellers had to travel back within four days of the announcement before the country moved to ‘amber’ with many who were planning to go there having to cancel their trips.