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Since the UK left the EU, travellers heading to all countries within the zone – and including Iceland, Norway, Lichtenstein and Switzerland, but not Ireland – must have a passport which was issued less than 10 years before their departure date.
It must also be valid for three months after their planned return date.
However, if a UK passport was issued before September 2018, it could in fact be valid for up to 10 years and nine months.From: Holidaymakers going to EU caught out by 10-year-passport rule – BBC News.
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