Hainan Airlines allows passengers to check in online starting 24 hours before the scheduled departure time for both domestic and international flights. Online check-in closes 60 minutes before departure. Passengers can use the Hainan Airlines website or mobile app to check in by entering their booking reference or ticket number along with their name. During online check-in, travelers can select their seats, confirm flight details, and receive a digital boarding pass that can be printed or saved to a mobile device. If the passenger has checked baggage, they should still go to the airport in time to drop off luggage at the designated bag drop area before the check-in deadline. Online check-in is not available for passengers who require special assistance, such as those traveling with infants, unaccompanied minors, or passengers needing wheelchair support. For airport check-in, Hainan Airlines recommends arriving at the airport at least two hours before departure for domestic flights and at least three hours before departure for international flights. Airport check-in counters usually open two to three hours before the flight and close 40 to 60 minutes before departure, depending on the airport and route. At the airport, passengers can check in at the service counter or use a self-service kiosk where available. It is important to carry a valid government-issued ID for domestic travel and a passport and visa for international travel. Travelers should also have any other documents required by their destination country. After checking in, passengers should proceed through security and reach the boarding gate on time. Boarding usually begins 30 to 40 minutes before departure and the gate closes 15 to 20 minutes before the scheduled departure time. Passengers who arrive late may be denied boarding. To avoid delays and ensure a smooth journey, it is best to complete check-in as early as possible within the available time window. Checking in early also gives travelers a better chance of selecting preferred seats. In summary, passengers flying with Hainan Airlines can check in online starting 24 hours before departure and must complete check-in at least 60 minutes before the flight. For airport check-in, travelers should arrive two to three hours before their flight depending on whether it is domestic or international. Being prepared with the correct documents and arriving early helps ensure a smooth and stress-free travel experience.