People who were fully vaccinated in the EU or US will not need to isolate when coming to England, Scotland and Wales from an amber list country.
The change will come into force at 04:00 BST on Monday.
Currently, only people who received their jabs in the UK can avoid quarantine when arriving from amber list countries, except France.
The UK government said the rule change would help to reunite family and friends whose loved ones live abroad.
Transport Secretary Grant Shapps said it would apply to people who have been fully vaccinated with a jab approved by the EU or US, with the final dose at least 14 whole days before arrival.
Travellers will still need to take either a lateral flow or PCR test pre-departure and a PCR test on the second day after they arrive.
Under-18s will be exempt from isolation, and some will not have to test, depending on their age.
It come as a further 27,734 cases were reported in the UK, bringing to an end a seven-day run of falling case numbers. Wednesday’s case figure was, however, down significantly from a week ago, when 44,104 cases were reported.
Another 91 deaths within 28 days of a positive test were also reported.
Tougher rules will continue to be in place for France, which is on the amber list but still requires travellers to quarantine when they return, even if they are fully vaccinated.
Mr Shapps said this advice would be reviewed at “the end of next week” as part of the rolling assessment of travel rules.