To facilitate an on-time departure, we recommend that you allow ample time for check-in, especially if you are checking baggage. For international departures, we recommend that you check in 2 hours before your flight. For additonal information about your airport, including security line waits, peak times and days of travel and other important information, see Airport check-in information.

When traveling around holidays or other peak travel times, we recommend you allow additional time.

Please note that reservations are subject to cancellation if you are not available for boarding at the boarding gate at least 20 minutes prior to departure for flights between U.S. points, to/from Canada, Mexico and the Caribbean; and 45 minutes to/from all other International points.

Countdown to departure:

• At 20 minutes before your flight:
  • We'll begin awarding upgrades and start accommodating customers who are waiting for seat assignments.
  • You'll have more time to board and store your carry-on baggage.
  • Occasionally, customers who check in less than 20 minutes before departure may lose their seat assignment/reservation when there are other customers waiting to be accommodated.
• At 5 minutes before your flight:
  • We'll close the door and prepare for departure.

There are certain circumstances that will contribute to delays (i.e. weather, air traffic, mechanical problems); however, United is committed to doing everything possible to ensure on-time departures on all flights.