U.S. IMMIGRATION INSPECTION BEFORE THE FLIGHT
At designated Canadian airports, U.S. Customs and Border Protection conducts immigration and customs inspection before the traveler boards the U.S.-bound flight. A traveler found inadmissible can therefore be stopped while still in Canada.
CBP Preclearance places U.S. officers at designated foreign locations so that U.S. immigration, customs and related inspection occurs before the traveler boards transportation to the United States.
CBP currently operates Preclearance at multiple Canadian airports, including major airports such as Toronto, Vancouver, Montreal, Calgary and others.
A Preclearance interview is a real U.S. admissibility inspection. The fact that the traveler is still physically in Canada does not mean the questioning is merely airline screening.
CBP states that travelers who would otherwise be found inadmissible on arrival in the United States can be stopped at the foreign Preclearance location before boarding.
The exact immigration disposition should be determined from the records generated during the inspection rather than inferred solely from the fact that the traveler did not board.
The same types of immigration questions that arise at a U.S. airport can arise during Preclearance, including questions about prior travel, employment, school attendance, criminal history and the purpose of the proposed trip.
A valid visa allows a traveler to seek admission in the relevant classification. CBP still decides whether the traveler is admissible and qualifies for the admission requested.
Current CBP guidance states that CBP no longer processes inadmissibility-waiver applications at Preclearance locations in Canada. Applicable nonimmigrant waiver cases may instead proceed through the Admissibility Review Office or consular process according to the governing procedure.
This does not mean that an already approved waiver becomes irrelevant at inspection.
No. CBP Preclearance includes U.S. immigration and customs inspection before travel.
Yes. A visa does not guarantee admission, and Preclearance is designed to resolve admissibility before the traveler reaches the United States.
Yes. The exact disposition should be identified because it can affect later visa applications and future U.S. travel.
These government materials provide the principal inspection and admission framework discussed on this page.
The legal consequences depend on whether the incident involved a simple refusal to continue travel, a documented inadmissibility finding, visa action or another immigration disposition.