United States border preclearance

United States border preclearance is a method of prescreening border control operated by the United States Department of Homeland Security to screen individuals seeking entry to the United States in eligible facilities located outside of the United States pursuant to agreements between the United States and host countries. Individuals are subject to immigration and customs inspections by U.S Customs and Border Protection (CBP) officers before boarding their method of transportation onward to the United States. Preclearance applies to all individuals regardless of their nationality or purpose of travel. Upon arrival, precleared passengers arrive in the United States as domestic travelers, however may still be subject to re-inspection at the discretion of CBP. This process is intended to streamline border procedures, reduce congestion at American ports of entry, and facilitate travel into airports that otherwise lack immigration and customs processing facilities for commercial flights.

The practice of prescreening U.S.-bound passengers in foreign countries began in 1894 when American immigration inspectors were deployed to sea ports across Canada. Modern preclearance facilities were first introduced in 1952 at Toronto Pearson International Airport and Calgary International Airport under an informal arrangement with the Government of Canada and are now available at eight major Canadian International airports and one seaport, while several other seaports and one rail station in British Columbia have "pre-inspection" facilities for screening immigration admissibility only.

United States border preclearance facilities have expanded in airports in Aruba, The Bahamas, Bermuda, Ireland, and the United Arab Emirates.