The UK’s traffic light system for travel has been scrapped and replaced with just two categories – countries on the red list and everywhere else.
The number of countries on the red list – currently 54 – is expected to be cut to as few as nine, with places such as South Africa, and Mexico expected to become available to quarantine-free travel.
People arriving in the UK fully vaccinated against COVID-19 – and everyone under 18 – will also see changes.
Those coming from countries not on the red list can enter the UK without a pre-departure test.
They do not have to take a PCR test eight days after their arrival or isolate at home.
Just a single test is needed on the second day after arrival in the UK.
It is unclear when this will change to a cheaper lateral flow test rather than a PCR version for vaccinated arrivals.
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The Department for Transport said the government “aims to have it in place for when people return from half-term breaks”.
Travellers, however, may still need to arrange tests depending on the requirements of airlines and their destination country.
There will be no change for those arriving from red list countries and they will still need to pay £2,285 for 11 nights in a government-approved quarantine hotel.
Transport Secretary Grant Shapps said: “We are accelerating towards a future where travel continues to reopen safely and remains open for good, and today’s rule changes are good news for families, businesses and the travel sector.
“Our priority remains to protect public health but, with more than eight in 10 people now fully vaccinated, we are able to take these steps to lower the cost of testing and help the sector to continue in its recovery.”
It comes after months of frustration for the travel sector, among the hardest-hit by the COVID-19 pandemic.
Tim Alderslade, chief executive of trade body Airlines UK, said: “Things are moving in the right direction and the removal of these restrictions will make it easier and cheaper for people to travel.
“We’ve seen a good response to the announcement in terms of bookings and given current trends we would hope to see more countries come off the red list and further mutual recognition of vaccine status.
“There is still much to do though. This is not job done, and ministers need to keep in mind that we remain an outlier on arrivals testing for vaccinated passengers.
“In the short-term the removal of PCR testing by the October half-term week is critical, and we look forward to clarity on the start date for this as soon as possible.”