Originally Posted by
HofstraJet
Unsure if there’s a separate US customs desk for connecting passengers, but assuming there isn’t, coming from a domestic Canada flight, you would have to go landside and enter the US transborder area.
Would be nice if you could connect airside to a transborder flight. Anyone know if that’s possible?
YUL has a dedicated connections line for transborder, similar to YYZ T1. Follow the purple signs from domestic airside. You'll have to go through CATSA again, but checked bags are automatically transferred. GE kiosks are also available.