Originally Posted by
SFO777
That has traditionally been the drill, although CBP at some airports (YYZ and YUL that I know of) has introduced a new system that does not require you to schlep your bags to US customs. They are checked thru to your arrival city. Not sure if it has been introduced in Calgary. OP, you might ask in the AC forum.
Calgary (YYC) does not have this system yet, buy YEG and YVR do!