United States border preclearance

The United States operates border preclearance facilities at a number of ports and airports in foreign countries. They are staffed and operated by U.S. Customs and Border Protection officers. Travelers pass through Immigration and Customs, Public Health, and Department of Agriculture inspections before boarding their aircraft, ship or train. This process is intended to streamline border procedures, to reduce congestion at ports of entry, and to facilitate travel between the preclearance location and U.S. airports unequipped to handle international travellers.

Preclearance exists at most major Canadian airports. Arrangements also exist with some airports in Bermuda, The Bahamas, Aruba, two airports in Ireland, and one in the United Arab Emirates. When travelers from a preclearance port arrive in the U.S. they do so as domestic travellers but are still subject to reinspection at the discretion of Customs and Border Protection.

Preclearance applies to U.S. citizens as well as citizens of most other countries who travel to the U.S. As United States and Canadian laws require that those in transit must pass through the relevant customs (unlike many other countries, which permit airside transfers), preclearance also applies to transit passengers.

This process is intended to streamline border procedures, to reduce congestion at ports of entry, and to facilitate travel between the preclearance location and some U.S. airports that may not be equipped to handle international travellers. However, with the exceptions of LaGuardia and Ronald Reagan Washington National Airport, many more US airports now have customs facilities compared to when the preclearance program first started in 1952.

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