As of September 11, 2026, an American travelling on a United States passport does not need a UK Electronic Travel Authorisation for a layover if the entire connection remains airside and the passenger does not pass through UK border control. If the connection requires border control, the traveller normally needs an Electronic Travel Authorisation, commonly called an ETA, unless another exemption or valid UK immigration permission applies. The airside exemption is temporary, is being kept under review and could change, so passengers should check the rule and their connection arrangements again before travelling.
The deciding factor is not simply the length of the layover or whether both flights appear on the same itinerary. What matters is whether the airport and operating airlines can transfer the passenger to the onward flight without requiring entry into the UK. An ETA is permission to travel, not a visa or a guarantee of admission at the border.
How to tell whether your connection is airside
An airside transit means that you stay within the airport’s international transfer area and do not pass through UK border control. A landside transit means that you pass through border control before returning through security for your next flight.
Use these questions to identify which type of connection you have:
- Must you collect checked baggage? If your bag is tagged only to the UK airport, you will normally have to pass through border control, collect it and check it in again. An American passport holder needs an ETA for that landside process.
- Are you changing airports? A transfer from Heathrow to Gatwick, for example, requires you to enter the UK and travel by road or rail. You need an ETA.
- Are you leaving the secure area? Going to a hotel outside the airside area, meeting someone in arrivals or visiting the city requires border control and therefore an ETA.
- Is the onward flight domestic? If you fly from the United States to Heathrow and then continue to Edinburgh, you enter the UK at Heathrow before taking the domestic flight. You need an ETA.
- Is the onward flight to Ireland or another part of the Common Travel Area? Passengers cannot transit airside to the Republic of Ireland, Jersey, Guernsey or the Isle of Man. You should expect to pass through UK border control.
- Has the operating airline confirmed an airside transfer route? If your baggage will be transferred and you can follow the airport’s flight-connections route without entering the UK, the temporary airside ETA exemption applies.
Do not confuse border control with airport security. Connecting passengers may have to undergo security screening again while remaining airside. A security check by itself does not mean that an ETA is required.
How tickets and baggage affect the answer
A single booking with baggage checked to the final destination is usually the arrangement most likely to support an airside connection. The airline may issue both boarding passes at the starting airport and transfer the checked baggage automatically. The passenger can then follow signs for connecting flights instead of entering the arrivals hall.
However, one booking does not guarantee an airside transit. The route may depend on the airports, terminals, airlines, destination and whether the passenger has the documents required for the next flight. Changing terminals does not necessarily require UK border control, but the airline should confirm the exact procedure.
Separate tickets create a much greater risk of a landside connection. Heathrow currently instructs self-connecting passengers who booked their arriving and departing flights separately to follow signs to arrivals, proceed through immigration, collect checked baggage, exit arrivals and check in again. That procedure requires an ETA for a United States passport holder.
Travelling with cabin baggage only does not automatically solve the problem. The second airline may require an in-person document check at a landside check-in desk, or the airport may not offer an airside route between the flights. Having a mobile boarding pass also does not prove that the transfer will remain airside.
Before leaving the United States, ask the operating airline whether your checked bag will be tagged to the final destination. Check the baggage receipt rather than relying solely on what appears in the booking confirmation. Flight disruptions can also change baggage and transfer arrangements, which is one reason some American travellers choose to obtain an ETA even when their planned connection should remain airside.
Special cases involving hotels and Ireland
Leaving the airport during a long layover requires an ETA. This includes sightseeing, meeting friends or family, changing airports and using a hotel that can be reached only after border control. The same rule applies even if the airline provides the hotel because of a delay or cancellation.
An overnight connection does not automatically require an ETA if the passenger can legally and practically remain airside. In reality, airport opening arrangements and accommodation options may make that difficult. At Heathrow, No1 Bedrooms in Terminal 3 is currently described as the airport’s only airside hotel. Its rooms are available from 6 a.m. until 10:30 p.m., rather than throughout the night. Heathrow directs passengers who need an overnight stay to nearby hotels, which generally requires entering the UK.
Do not assume that you can sleep in a terminal until the next flight. Ask the airport and airline whether passengers may remain airside overnight, whether the flight-connections area stays accessible and whether you will have access to your onward departure terminal. If you must leave the secure area, you need an ETA.
Connections to the Republic of Ireland need particular attention. Flights from UK airports to Ireland operate within the Common Travel Area, so an international passenger cannot make an airside transit directly to Ireland. An American flying from New York to Dublin through London should therefore plan to pass through UK border control and obtain a UK ETA. Ireland has separate entry requirements, and meeting the UK rules does not establish permission to enter Ireland.
These conclusions are specific to travellers using United States passports. The ETA is different from a transit visa. People travelling on passports from other countries may need a UK visa even for an airside connection, depending on their nationality and documents. They should use the official UK visa and ETA checker rather than assuming that the rules for Americans apply to them.
What to confirm and how to apply
If there is any uncertainty, contact the operating airline, not only the travel agency or website that sold the ticket. Provide the travel date, both flight numbers, ticket details and baggage arrangement. Ask the following:
- Will I follow an airside flight-connections route?
- Will I pass through UK border control or enter the arrivals hall?
- Will my checked baggage be transferred to my final destination?
- Will I receive my onward boarding pass before arriving in the UK?
- Does changing terminals or airlines require a landside check-in?
- Can I remain airside if the connection is overnight?
If the airline cannot confirm that an American passenger will remain airside, obtaining an ETA before departure is the safer practical choice. It can also provide flexibility if a disruption requires a hotel stay, baggage collection or a new landside itinerary. Remember, however, that an ETA does not guarantee entry; a UK Border Force officer may still assess the traveller on arrival.
Apply only through the official UK ETA app or the GOV.UK online service. The current fee is £20 for each applicant. You need the passport you will use for travel, an email address, a photograph of the applicant’s face and an accepted payment method. Every traveller needs a separate ETA, including babies and children.
Decisions usually arrive by email within one day, but processing can take up to three working days. Wait for the approval email before travelling. The ETA is digitally linked to the passport used in the application and normally remains valid for multiple journeys for two years or until that passport expires, whichever occurs first. A new or changed passport requires a new ETA.
Because the airside exemption is explicitly temporary, check the official rule shortly before departure. Also recheck it if an airline changes your airport, terminal, ticket or baggage instructions. For an American passport holder under the rule in force on September 11, 2026, the practical distinction remains clear: an entirely airside layover does not require an ETA, while a connection through UK border control normally does.
