The geographic territory upon which a sovereign nation imposes its import and export regulations and duties. Certain territorial possessions and special economic zones (such as foreign trade zones) are often considered outside the customs territory of a nation.
(U.S. Customs) The customs territory of the United States consists of the 50 states, the District of Columbia, and Puerto Rico. Foreign trade zones are not considered customs territory of the United States. See United States Customs Service; foreign trade zone.