When entering the U.S. from overseas, travelers must pass through immigration and customs at the airport. However, U.S. Customs and Border Patrol or CBP, has set up “preclearance” points at several international airports in cooperation with local authorities, which allow travelers to complete immigration formalities at the departure airport before their flight. Once they land in the U.S., they step off the plane like an arriving domestic traveler would, and do not need to undergo any arrival inspections or paperwork.

This program is popular with frequent travelers because it means you don’t spend additional time waiting when you land in the U.S. Here’s a rundown of the program and where you can take advantage of it.

How does U.S. preclearance work?

First: Standard airport security and departure formalities

U.S. preclearance facilities are a secondary step to the traditional departure processes for the country you are exiting. First, travelers undergo airport security as they would on any flight, then, they complete any immigration requirements to exit the country (immigration is before security in some airports). This leaves travelers within the airport terminal where shops, lounges, dining and other amenities are.

Second: U.S. preclearance formalities

U.S.-bound travelers at an airport with preclearance should then leave ample time to go through CBP immigration, which they must pass through to reach the departure gate.

Often, there is a second round of security to pass through (it depends on the airport), and since this is still a foreign country, expedited security programs like Clear and TSA Precheck are not available.

Like arriving in the U.S., travelers complete any necessary forms (whether paper or via kiosk), and then approach an officer for any potential questioning. All preclearance airports have separate lanes for travelers with Global Entry. Conversely, you’re unlikely to find any using Mobile Passport.

Checked bags from the ticket counter may need to be recollected to go through immigration and customs. This is the case in some, but not all, airports with CBP preclearance. Next, you would redeposit your luggage on the other side of immigration with bag tags to your final destination. These are screened like they would be upon arrival in the U.S., which may include an officer opening your bag and inquiring about items in it.

Once you've passed successfully through preclearance immigration, you can proceed to your gate for your U.S.-bound flight.

Pro tip: Don’t forget the rules

Many travelers may overlook the strict list of prohibited items at this point because they have not yet physically arrived in the U.S. Beware that if you're traveling with things like fruits, meat, cheese and other items that must be declared, you must do so during the preclearance process.

Even though you're not physically in the U.S. yet, you're completing the formalities at the departure airport. That means the apple or banana in your carry-on bag that you planned to eat on the flight must be discarded before going through preclearance, otherwise you might be fined.

Which airports offer U.S. border preclearance?

Preclearance facilities are available at 15 airports and one cruise port around the world. They are often a source of pride for an airport as they make better use of travelers’ time and speed up the process for after you land. In effect, it becomes a marketing tool they can use to attract travelers looking for the fastest journey.

Preclearance locations

Abu Dhabi.

Aruba.

Bahamas - Freeport.

Bahamas - Nassau.

Bermuda.

Calgary.

Dublin.

Edmonton.

Halifax.

Montreal.

Ottawa.

Shannon.

Toronto.

Vancouver.

Victoria, Canada (cruise port).

Winnipeg.

Preliminary discussions are in place to add preclearance to airports in Amsterdam, Bogota, Brussels and Stockholm, among others. Since they require significant infrastructure development at an airport to reconfigure the terminal layout for immigration facilities, it is something that can take time to implement.

Pros and cons of U.S. preclearance

Pros

✅ time saver upon arrival

The major benefit of preclearance is that when you finally reach the U.S., you land as a domestic passenger and can head straight for baggage claim or your connecting flight saving valuable time.

✅ safety

According to U.S. Customs and Border Control, preclearance also has the benefit of stopping potential security threats before arriving onto U.S. soil, as well.

✅ more airports can host international flights

These facilities also open up new service to U.S. airports that don’t have substantial customs and immigration facilities of their own. By completing these formalities at the departure airport, smaller airports like Hartford, Connecticut (which is serviced from Ireland) can more easily accept international flights.

Cons

❌ more time spent boarding your departing flight

Unfortunately, this means that at the departure airport for your U.S.-bound flight, there will be extra items on your to-do list. If there are multiple U.S.-bound departures leaving around the same time, lines can be long, meaning it is wise to arrive with plenty of time.

❌ potential for connection hiccups

Also, if you're making a connection at an airport with preclearance, you’ll need to allow ample time to do so. For example, if you’re flying from Madrid to Boston with a connection in Dublin, you’ll need to allow plenty of time to land from Madrid and pass through U.S. preclearance immigration in Dublin before heading for your Boston-bound gate.

Any delays landing in Dublin could cause you to miss your connection to Boston as you would be required to pre-clear U.S. immigration there.

The bottom line

Overall, just be sure you know if you’re heading through a preclearance airport on your journey so you can be prepared accordingly. If you like the idea of preclearance, you can prioritize those airports when planning international trips and booking your return flights.