So I always thought this wasn't allowed. Even on award tickets, in the rules it always says "25k miles - Wholly within USA and Canada", but when you try to book a ticket between 2 Cdn. cities on DL or AA for example which I have tried in the past, it just says "this routing pair not allowed".

Today while looking for a UA award ticket YUL-YVR, assuming it would be an AC Star award, I was given the routing YUL-IAD-ORD-YVR and YVR-DEN-ORD-YUL on the return. Anyone else see that before? Must be interesting when going through customs....

-mike