Passengers heading to the UK with a supposedly valid ETA might be turned away at the airport if they forget this crucial piece of travel preparation.
News emerged on Friday that four French rugby players were denied entry into the U.K. because of an issue with their electronic travel authorisation, known as an ETA.
According to the reporting from AFP, "four Bordeaux-Bègles players, including France winger Louis Bielle-Biarrey, were stranded at Bristol Airport after being denied entry into the UK because of an administrative issue on the eve of their Champions Cup opener against Gloucester."
The four players, it emerged, along with a coach travelling with them, did not have "valid Electronic Travel Authorisation (ETA) permits, which are required for entry into the UK."
A source told AFP that their ETAs were linked to expired passports, revealing a little-known travel rule that passengers arriving in the UK should be aware of.
If not, passengers could be turned away at the border like the French rugby players.
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Why travellers need to remember ETA when renewing passports
The UK's ETA visa waiver is a requirement for all nationalities apart from British and Irish so that includes nationals from EU and EFTA countries (Switzerland, Iceland, Norway, Liechtenstein) as well as Americans, Canadians, Australians etc who are living in Europe.
It's also required for family members of British nationals - if they don't have a UK/Irish passport.
That means anyone travelling to the UK will need to arrange this travel authorisation online - with the exception of those who are travelling on a British or Irish passport, or anyone who has residency in the UK.
Like the EU's version postponed ETIAS, it is modelled on the USA's ESTA visa waiver, and is required for all types of travel including tourism, short stays and family holidays.
As the Bordeaux players' ordeal at Bristol Airport demonstrates, travellers to the UK from Europe must remember that their ETA is linked to their passport - so if a passport is renewed you also need to get a new ETA or you could be denied entry to the UK.
According to the Gov UK site: "An ETA lasts for 2 years and is linked to your passport. If your passport has expired or changed, you’ll need to apply for a new ETA."