After Jan 2025 do airlines deny boarding to UK citizens flying to UK with only a US passport?

Question

UK citizens who have permanently relocated to USA have long been able to travel to the UK with only their US passport. Infrequent travelers could avoid the hassle and expense of renewing their UK passports.

Since January 8, 2025, US citizens need a UK ETA to enter, and UK citizens cannot get one.

An expired UK passport, or other UK document showing citizenship is acceptable for entry to the UK but not necessarily acceptable to airline check-in staff in the USA who must enforce the ETA rule.

Have airlines begun turning away passengers at US airports flying to the UK who have some proof of UK citizenship but not a valid UK passport or a UK ETA?

Answers to this question should be based either on personal experience since Jan 8 2025, or on clear knowledge of any airline's policy and training of US airport staff on this specific topic.

Answer 1

According to the UK Govt website page Apply for an electronic travel authorisation (ETA), dual citizens must possess a valid UK passport. So evidently an expired one, or other paperwork showing UK citizenship, will not do.

Dual citizens

If you are a dual citizen with British or Irish citizenship, you do not need an ETA. Prove your permission to travel using a:

• valid British passport
• valid Irish passport
• other valid passport containing a certificate of entitlement.

Answer 2

[ Writing a wiki answer here to incorporate comments above and my own better understanding of the documented rules. ]

ETA enforcement is designed to be by airlines. The airlines are given rules that are simpler than actual immigration law, and therefore more restrictive. As @Elwyn points out, the guidelines say "valid" UK passport. Immigration agents can navigate exceptions and nuances of law in ways that airline agents are not expected to do. My question about airline training is misplaced. They just have to follow the guidelines.

Comments from @Traveller and @Giacomo above correctly point out that airlines mostly will not ignore the guidelines in order to interpret UK immigration law in the way that UK immigration agents would do. You can arrive in the UK without an ETA or a valid UK passport ---- but not by plane. Relying on your check-in AND your gate agent to both go above and beyond FOR YOU will have very small odds.

Answer 3

If you have enough time, renewing the UK passport is easiest

It appears that the UK has significantly streamlined the passport application process for British people living abroad, as evidenced by this comment from jay613:

FWIW I just renewed mine online for the first time in decades, and it was 20% the effort and 33% the cost of doing it via the Washington Embassy last time I tried. Writing this question was more effort than applying.

So it looks like the simplest solution to avoid the conundrum is to... go ahead and renew your UK passport before you travel. There are two options, depending on how much time you have left:

• Apply for a regular passport, which should take 4 weeks to process.
• Apply for an 'emergency travel document', which can be ready in as little as 2 working days depending on your circumstances.

Alternatively, if you end up returning to the UK with an expired passport, you could also consider getting it renewed at a Passport Office during your trip. You can currently do this in as little as 2 working days by paying for urgent domestic service.

Next best alternative: apply for an ETA

The official ETA guidance uses the following language:

If you are a dual citizen with British or Irish citizenship, you do not need an ETA.

This tells us that while UK citizens don't need an ETA, there's nothing stopping them from applying for an ETA on their second passport. In other words, UK citizens are not banned from applying for an ETA. In fact, as of March 2025, it's not even possible to declare yourself as a British citizen when submitting an ETA application:

The What is your other nationality? section simply lacks the option to declare yourself a 'British citizen', which is the formal legal name for 'regular' UK citizens. The other 5 types of 'British' nationalities don't grant automatic right of abode in the UK, although British Nationals and Overseas Citizens are exempt from the ETA requirement.

Thus, if you don't have enough time to renew your UK passport, you should instead apply for an ETA using your US passport. If approved, you can use your US passport to travel to the UK, just like any other American. Show your US passport alone to the airline, then show your expired UK passport to UK immigration upon arrival. The vast majority of dual citizens should be able to obtain an ETA without any issues.

Alternatives if you can't get an ETA

If you're very unlucky and your ETA application is rejected, you still have three more options thanks to being a UK citizen. It's worth emphasizing that none of these options violate UK laws, as you are a UK citizen with the right to enter the UK.

1. Enter the UK via Eurostar

Book a ticket to Paris (or another city with Eurostar service), then take the Eurostar train to London. UK immigration checks ('juxtaposed controls') occur before boarding the Eurostar when traveling from continental Europe. Show your US passport to French immigration and then show the expired UK passport to UK immigration. Since immigration happens before departure, Eurostar doesn't care what documents you have and won't stop you as long as UK immigration lets you through. Bonus points if you book Seat 61.

2. Enter via (Northern) Ireland

Book a ticket to the Republic of Ireland. From there, you have two options depending on what documentation you have:

a. If you have valid photo ID issued in the UK, such as a UK driving license, student card, bus pass with a photo, etc., you can fly directly from Ireland to the UK without a valid UK passport. The list of accepted documents depends on the airline; see this related question for details.

b. If you don't, you could instead take a bus or drive to Northern Ireland and then take a domestic flight to your final destination in the UK. The Irish land border remains uncontrolled due to the Good Friday Agreement, and you're within your rights to cross it as a UK citizen regardless of what documents you happen to carry with you.

This complexity is only required for the inbound trip; for the outbound, you can leave on a direct flight to the US.

3. Book a connecting flight via the UK, but enter the country instead of transiting

This option is only for experienced travelers for reasons described in this answer. According to Timatic:

Exemptions for Electronic Authorization

Nationals of USA can transit airside through Manchester (MAN) or London Heathrow (LHR) without an Electronic Travel Authorisation (ETA) on the same calendar day.

Therefore as long as:

1. You have a connecting flight transiting Heathrow or Manchester airport.
2. The connection is on a single ticket and on the same calendar day.
3. You only have carry-on luggage (as you won't be able to retrieve any checked luggage).
4. Your final destination is in a country you can enter visa-free on your US passport.

... the airline will let you board the flight to the UK. Once you reach the UK, simply head towards immigration instead of going to your connecting flight. Show your expired UK passport and you should be good to go. This might be a violation of the airline's T&Cs but it's not against the law.