Customs territory. Customs territory is the territory of the U.S. in which the general tariff laws of the U.S. apply. Customs territory of the United States includes only the States, the District of Columbia, and Puerto Rico. (General Note 2, Harmonized Tariff Schedule of the United States (19 U.S.C. 1202)).
19 CFR § 146.1
The following words, defined in section 1 of the Foreign-Trade Zones Act of 1934, as amended (19 U.S.C. 81a), are given the same meaning when used in this part, unless otherwise stated: Board, Grantee, and Zones.