U.S. regulations always require travelers to comply with customs and immigration procedures at their first point of entry into the U.S. Travelers will need to have all required documents with them upon arrival — even if the U.S. is not their final destination. If travelers have more than one U.S. stopover, they will not need to clear customs again. https://www.united.com/ual/en/ca/fly/travel/documentation-requirements/international.html
U.S. regulations always require travelers to comply with customs and immigration procedures at their first point of entry into the U.S. Travelers will need to have all required documents with them upon arrival — even if the U.S. is not their final destination. If travelers have more than one U.S. stopover, they will not need to clear customs again. https://www.united.com/ual/en/ca/fly/travel/documentation-requirements/international.html