Join Date: Aug 2002
Location: WAS, FLL
Programs: AA, B6, CO, DL, FL, UA, US Gold (only took 10k miles), WN, Amtrak
Posts: 1,299
As everyone else has said you will go through US entrance formalities in YVR. Once you hand your bag over to the NW agent in YVR you will not touch it again until you arrive at your destination airport.