US Preclearance is a system that allows some passengers travelling to the United States to complete US immigration, customs and agriculture checks before they leave the country they are flying from.
Instead of reaching America and then joining the usual international arrivals process, passengers who have successfully completed Preclearance are generally treated as domestic arrivals when they land in the United States.
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For autistic travellers, disabled travellers and families, this can change the order of the airport journey quite significantly. You may have an extra border-control stage before boarding, but a simpler arrival after a long flight. Knowing what happens in advance can make the process easier to prepare for.
What Is US Preclearance?
US Preclearance is operated by U.S. Customs and Border Protection (CBP) at selected locations outside of the United States. CBP officers and agriculture specialists are stationed at designated foreign airports and other approved locations so they can inspect eligible US-bound passengers before departure.
The inspection is broadly the same type of process that would normally happen when you arrive at a US port of entry. The important difference is that it takes place before you board your US-bound journey.
What Checks Are Completed During Preclearance?
At an airport offering full US Preclearance, passengers can complete the main border checks that would otherwise take place on arrival in the United States. These can include:
- US immigration inspection.
- Customs checks.
- Agriculture inspection.
- Inspection of personal belongings and baggage where required.
- Questions relating to your eligibility to enter the United States.
CBP may ask about your trip, where you are staying, what you are bringing into the country or other matters relevant to admission into the United States.
What Happens After You Complete US Preclearance?
Once you have successfully completed Preclearance, you continue to your departure gate and board your flight. When you arrive in the United States, you normally bypass the standard CBP and immigration process for international arrivals. You can generally proceed in the same way as a domestic arriving passenger, following the airport’s instructions for baggage collection, onward connections or leaving the terminal.
This can be particularly useful when connecting to another flight within the United States because it removes a major arrival-stage process from the connection.
Where Is US Preclearance Available?
US Preclearance is only available at selected locations outside the United States. CBP currently operates Preclearance in Canada, Ireland, Aruba, The Bahamas, Bermuda and the United Arab Emirates.
Locations include airports such as Dublin and Shannon in Ireland, Abu Dhabi in the United Arab Emirates, Nassau in The Bahamas and a number of major Canadian airports.
Participating locations and the type of Preclearance offered can change, so always check the current U.S. Customs and Border Protection Preclearance information before relying on it for a particular journey.
Does Every Flight From a Preclearance Airport Use It?
No. Flying from an airport that has a Preclearance facility does not automatically mean that every US-bound service will use it.
The availability of Preclearance can depend on the airport, terminal, airline, route and operating arrangements. If you are unsure, check with your airline and the departure airport before travelling.
US Preclearance in Ireland
Ireland has US Preclearance facilities at both Dublin Airport and Shannon Airport.
At Dublin Airport, most direct US flights departing from Terminal 2 use Preclearance, although Dublin Airport advises passengers to confirm whether it applies to their specific flight.
Dublin Airport describes the process as completing US immigration, customs and agriculture inspections before departure. Passengers who have been precleared generally do not repeat those checks when they land in the United States.
If you plan to fly to the US from Dublin we have some guides which can help you navigate Dublin and the airport before your flight:
- Ireland with autistic children country guide
- Dublin with autistic children travel planning guide
- Disabled facilities available at Dublin Airport
- Special assistance at Dublin Airport
Do You Need an ESTA If You Use Preclearance?
Preclearance does not replace the normal entry requirements for the United States. If you are travelling under the Visa Waiver Program, you still need an approved ESTA where required. If you need a US visa for your nationality or circumstances, you still need the correct visa.
Preclearance is the place where your admissibility is checked before departure. It is not itself permission to travel to or enter the United States.
Do You Still Need Your Passport?
Yes. You still need the physical passport and any other travel documents required for your journey.
Keep passports, boarding passes and relevant supporting documents easy to reach before entering the Preclearance area. Families may find it useful to keep everyone’s documents together in one organised travel wallet.
Learn more about passport validity and how long you must have left on your passport when travelling to the US.
What Happens to Checked Baggage?
Baggage arrangements vary by airport and itinerary, but at full airport Preclearance locations the process is designed so that passengers do not normally need to repeat the standard international customs process when they arrive in the United States.
Always confirm your baggage arrangements with your airline, especially if you have an onward connection, separate tickets or an unusual itinerary.
Food, Medication and Items You Are Bringing Into the US
Because customs and agriculture checks can take place during Preclearance, the rules covering items entering the United States still apply before you board. This matters for families carrying familiar foods, specialist foods, allergy-safe products or snacks for sensory reasons. Certain food and agricultural products can be restricted or prohibited.
If you are unsure whether a food item needs to be declared, declare it and let CBP decide whether it can enter the United States. Do not assume an item is permitted simply because it was bought at your departure airport.
Prescription medication should remain accessible in your hand luggage where appropriate, together with any supporting documentation you may need. Check the current US rules for the specific medication before travel. Our guide breaks down what to include on a doctors letter for travelling with medication so you can get it right the first time.
What Is the Difference Between Preclearance and Normal US Immigration?
The main difference is where the border inspection happens.
Without Preclearance, you usually fly to the United States and complete CBP immigration, customs and agriculture procedures at your first US port of entry.
With Preclearance, those checks happen at the participating airport or approved location before you depart. This means your US arrival is normally much closer to a domestic arrival.
Does Preclearance Mean You Are Guaranteed Entry to the US?
No. Preclearance does not guarantee that you will be admitted to the United States.
CBP officers carry out the admission inspection before departure. If there is an issue with your eligibility to enter the United States, it can therefore be dealt with before you board rather than after you arrive in America.
What Is the Difference Between Preclearance and Mobile Passport Control?
US Preclearance and Mobile Passport Control (MPC) are not the same thing.
Preclearance is the physical US border inspection that takes place outside the United States. MPC is an optional CBP app that allows eligible travellers to submit some travel document, photograph and customs information electronically.
At some Preclearance locations, including Dublin Airport, eligible travellers can use MPC as part of the process. You still need to complete the actual CBP inspection.
Is Preclearance the Same as Global Entry?
No. Global Entry is a separate Trusted Traveller programme for pre-approved eligible travellers.
Some Preclearance facilities support Global Entry processing, but having Global Entry and travelling through a Preclearance airport are two separate things.
Is Preclearance the Same as Airport Security?
No. Airport security screening and US Preclearance are separate processes.
Security screening checks passengers and baggage for aviation-security purposes. Preclearance deals with entry into the United States, including immigration, customs and agriculture requirements.
Depending on the airport, you may therefore complete normal airport security and then continue to a separate US Preclearance area.
US Preclearance for Autistic Travellers
For an autistic traveller, Preclearance changes the usual sequence of an international airport journey. Instead of completing border control after landing, there is an additional formal process before boarding.
It may help to prepare a simple sequence in advance, for example:
check in → airport security → US Preclearance → wait at the gate → board the flight → land in the US → collect baggage or connect
Border officers may ask questions, and there may be queues or waiting periods. Keeping documents organised, explaining the order of events beforehand and allowing enough time can make the process more predictable.
If you are planning a wider trip, our United States with autistic children guide covers practical family travel planning.
US Preclearance for Disabled Travellers
Preclearance does not replace airport special assistance. If you need mobility support, help navigating the airport, assistance with queues or another adjustment, arrange the relevant assistance through your airline and departure airport where required. You can learn more about airport assistance in our guide to getting help at the airport if you have a disability.
If verbal communication is difficult, a travelling companion may be able to help explain support needs, although CBP officers may still need to ask the traveller questions directly where appropriate.
How Much Extra Time Should You Allow?
There is no single Preclearance arrival time that applies to every airport. Follow the advice from your airline and departure airport. Remember that Preclearance adds another stage before boarding, so do not plan your airport arrival as though you were taking a normal domestic or short-haul flight. For example, Dublin Airport currently recommends arriving three hours before a long-haul flight and allowing additional time when checking baggage or travelling in a group.
Advantages of US Preclearance
- You complete the US border process before flying.
- You normally avoid the standard international immigration queue when you land.
- Domestic connections in the United States can be easier.
- Potential entry issues can be identified before you board the flight.
- For some travellers, completing formalities before a long flight may make the arrival experience less demanding.
Things to Consider Before Using US Preclearance
- Allow enough time for the extra airport stage.
- Check whether your specific flight uses Preclearance.
- Keep passports and entry documents easy to reach.
- Check rules for food, medication and agricultural products.
- Arrange airport disability assistance separately if required.
- Prepare autistic travellers for questions, queues and the change in airport sequence.
- Check whether facilities such as shops, lounges and restaurants are limited after the Preclearance area.
Frequently Asked Questions About US Preclearance
Do you go through US immigration before flying?
If your departure airport and flight use US Preclearance, yes. You complete the US admission process before boarding your US-bound flight.
Do you go through customs again when you land in the US?
Passengers who have successfully completed full airport Preclearance normally do not repeat the standard CBP customs and immigration process when they arrive in the United States.
Can you be refused entry during Preclearance?
CBP decides whether a traveller is admissible to the United States. Completing Preclearance does not guarantee admission, so an entry problem can arise during the inspection before departure.
Is Preclearance compulsory?
If your flight is processed through a US Preclearance facility, completing the required border inspection is part of the departure process. However, not every US-bound flight from an airport with a Preclearance facility necessarily uses it.
Does Preclearance make US connections easier?
It can. Because you normally arrive as a domestic passenger, you do not first have to join the standard international CBP queue before continuing your journey.
Can disabled passengers use special assistance through Preclearance?
Airport assistance arrangements vary by location. If you need support, request it through your airline and departure airport and ask how assistance continues through the Preclearance part of the journey.
Check the Latest US Preclearance Information
US immigration procedures, participating locations and individual airport arrangements can change. Before travelling, check the current CBP Preclearance guidance, your departure airport and your airline.
Continue Planning Your Trip to North America
We already have a growing collection of North America guides ready for you to read and will continue to add more as we visit more places.
- Start with my North America with autistic children guide to help plan your overall trip
- Planning a trip to the USA? Read my United States with autistic children family travel guide
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- Start planning your visit to Guadeloupe with autistic children
- Learn more about visiting Martinique with autistic children
- Use my Sint Maarten with autistic children guide to plan your time on the island
- Find out what to expect when visiting St Kitts and Nevis with autistic children
Continue Planning Your Trip With Autistic Children
- Find out about the help available if you are travelling through an airport
- Discover whether a cruise with an autistic child would work for your family
- Find out how to make travelling with ADHD manageable
- Learn more about the Hidden Disabilities Sunflower Lanyard
- Check out guides to all of the different destinations we have travelled to with autistic children
- Learn step-by-step how to set up the accessibility feature on Google maps
- Learn more about our favourite sensory toys for travelling
- Discover an app that helps you locate a playground anywhere in the world
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Continue Planning Your Accessible Trip With Our Guides
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