Originally Posted by
sydneyracquelle
Yes by land but an airline might not let you board a flight to Canada without a passport. Most US gate agents don’t know what a Nexus is. You’ll probably have more luck with AC than US airlines.
I wouldn't count on having more luck with AC. In my experience Canadian airlines, including AC, require a passport before boarding a flight from the U.S. to Canada even if you booked the flight with a NEXUS. I use NEXUS when driving to the U.S but always bring the passport when flying or if driving an extended distance in America.