The constraints on how early you can come vary depending on how early I can check in with Air Canada. The check-in and boarding processes may be impacted by the airport and the destination.  how early I can check in air canada trip also depends on the kind of flight.For flights run by partner airlines, different rules apply. Therefore, once the flight is booked, confirm the times. Start the process early to allow for immigration and security processes. It may take a while to print a pass or finish any other formalities.The mode of check-in determines how early you can arrive at Air Canada. The check-in and boarding procedures may be affected by the airport and the destination. How early you can check in for an Air Canada trip also depends on the kind of flight.Therefore, once the flight is booked, confirm the times. Start the process early to allow for immigration and security processes. It may take a while to print a pass or finish any other formalities.