When departing a flight bound for the United States, you will need to go through security screening as well as customs screening by a U.S. Customs and Border Protection (CBP) officer before your departure.
YUL provides border preclearance for passengers bound for the United States. You will therefore not have to submit to any other formalities when arriving in the United States.
You must have all the required documentation to enter the United States with you, including a valid passport.
If you would like to find more about the U.S. Customs and Border Protection and their services, please visit their website,
You can also speed up U.S. entry processes by using the Mobile Passport Control (MPC) app.