British dual nationals who don't have a British passport could be stopped from entering the UK under new rules coming into force later this month.
British dual nationals will no longer be able to enter the UK using only a foreign passport, as the government starts enforcing its Electronic Travel Authorisation (ETA) scheme from 25 February.
To board a flight, they must present a valid British passport or a Certificate of Entitlement - which costs £589 - or risk being denied boarding.
Travellers face being blocked from boarding their flight, ferry or train if they don't have one of these.
Although British and Irish citizens are exempt from applying for an ETA, airlines must now check passengers have the correct documentation before departure.
Non-visa nationals from 85 countries must also have an ETA before travelling, as part of the government's move towards a fully digital border system.
British and Irish citizens have the right to live in the UK, although they must prove this right when entering at the border.
Dual nationals used to be able to travel on a foreign passport without a certificate of entitlement, which links their right to reside in the UK to their foreign passport - although they risked being delayed by Border Force staff confirming their citizenship.
What should dual nationals do?
From 25 February, dual nationals will need to present either a British passport or certificate of entitlement to enter the UK.
At £94.50, applying for a British passport is much cheaper than a certificate of entitlement - which costs £589.
The Home Office says it has advised dual nationals to make sure they have the right documents to enter the UK since October 2024, and has been advertising about the ETA changes since 2023.
"Without [a British passport or certificate of entitlement], carriers cannot verify they are a British citizen, which may lead to delays or refused boarding," a spokesperson said.
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It's not possible to get an ETA or visa to enter the UK as a British citizen, so dual nationals will either need a passport or certificate of entitlement.
Those who already have a physical certificate of entitlement will automatically receive a new digital version.
But they will need to create a UK Visas and Immigration (UKVI) account to link it to their foreign passport.
Irish citizens can continue to use their Irish passport to enter the UK.
Why are the changes happening?
ETAs are part of what the government says will be a "more streamlined, digital immigration system" that it hopes will mean quicker entry into the UK, reducing queues at the border.
It also says the system will be more secure, and prevent people who shouldn't be entering the UK from doing so.
An ETA costs £16 and allows for multiple journeys and UK stays for up to six months, although it only last for two years.
The government plans to raise the cost to £20 at some point in the future.
It's similar to changes being made in the European Union, where non-EU citizens now need a European Travel Information and Authorisation System (ETIAS) authorisation to enter.
(c) Sky News 2026: Dual nationals who don't have British passport could be denied UK entry

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