FWIW, CO flies to a bunch of destinations in Canada as well...
Moncton, Halifax, St. John's, Quebec City, Montreal, Ottawa, Toronto, Calgary & Vancouver.
Partner service (I'm pretty sure NW-operated, though some may be AS) goes to Victoria, Kamloops, Kelowna, Edmonton, Saskatoon, Regina, Winnipeg, Thunder Bay and London.
None of it stays in Canada.