U.S. border preclearance

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

Preclearance exists at most major Canadian airports. Arrangements also exist with some airports in Bermuda, The Bahamas, Aruba, Ireland, and the United Arab Emirates. Passengers traveling from a preclearance port arrive in the United States as domestic travelers, 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 United States. As U.S. and Canadian laws require those in transit to pass through customs (unlike many other countries, which permit airside transfers), preclearance also applies to transit passengers.

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

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