Visit the Cathay Pacific website or Cathay Pacific app. You can easily and quickly check in for your flight, select the seat you like and manage your travel arrangements via both these platforms. For most international flights, you're able to check in from 2 days to 1 hour and 30 minutes before wheels up. However, based on your flight and destination, you may need to check in at the airline counter if further passport information or other documentation is required. If you're traveling on a domestic airfare, you can check in for most flights online from 1 day to 1 hour and 30 minutes before takeoff.