Online If you are eligible for online check-in, go to united.com/checkin. Enter your confirmation or eTicket number and last name, or log in using your MileagePlus® account information. Use a printed boarding pass or electronic boarding pass on your mobile device to board the flight. How to Do Online Check-In with United Airlines As of June 2025, United Airlines has updated its check-in policies, particularly for domestic flights. Understanding how and when to check in online is essential for ensuring a smooth travel experience and avoiding last-minute issues at the airport. Updated Check-In Deadlines Domestic Flights: All passengers must check in at least 45 minutes before departure (previously 30 minutes). International Flights: Check-in closes 60 minutes before departure. Missing the cut-off may result in denial of boarding, cancellation of your reservation, or inability to check baggage. Steps to Check In Online or Via the United App You can check in starting 24 hours before your scheduled departure time, up to the appropriate deadline. Step-by-Step Instructions: Go to united.com or open the United mobile app.[1_866 551 1186 Select "Check-In" from the homepage or main menu. Enter your confirmation number or e-ticket number and your last name. Select the passenger(s) and review your itinerary. Choose or confirm your seat assignments. Add any additional services, such as checked baggage or upgrades, if needed. Submit and receive your boarding pass, which can be: Downloaded as a PDF Emailed to yourself Saved to Apple Wallet or Google Pay Online and mobile boarding passes often update in real time if there are gate or departure changes. Eligibility for Online Check-In Not all passengers are eligible for online check-in. You may not be able to use this feature if: You are an unaccompanied minor or traveling with someone who needs special assistance You are traveling with a pet You have a Basic Economy ticket and have not indicated whether or not you are checking baggage Your itinerary includes more than four flight segments or more than nine passengers You are using a paper ticket Your flight includes a segment operated by a partner airline that does not support online check-in through United In these situations, you will need to check in at the airport using a kiosk, at the ticket counter, or directly at the gate (if time allows). Additional Airport Check-In Options Curbside Check-In Available at many U.S. airports Open from 4 hours to 30 minutes before departure Especially useful if you are being dropped off and need to check bags Self-Service Kiosks Available in most U.S. airports Open around 3 hours before departure Close at the same time as airport counter check-in deadlines (45 minutes for domestic, 60 for international) Can be used to print boarding passes, tag checked baggage, and modify seat selections Ticket Counter Check-In Opens approximately 3 hours before departure Closes: 45 minutes before departure for most domestic flights 60 minutes or more before departure for international flights Voice Check-In Call 1-888-UNITED-1 ([1_866 551 1186) for domestic or Canada-based flights Available if fewer than 10 passengers are on the reservation You can check in, add baggage, and request that boarding passes be sent via email or printed at the airport Auto Check-In for Return Flights If your return or connecting flight departs within 24 hours, you can opt into auto check-in. United will automatically check you in and send your boarding pass via email, app, or kiosk, depending on your settings. Timing and Arrival Recommendations To avoid missing your flight, United recommends arriving well before your departure time. Flight Type Online Check-In Opens Check-In Closes Recommended Airport Arrival Domestic Flights 24 hours before 45 minutes before 2 hours before departure International 24 hours before 60 minutes before 3 hours before departure Note that arrival time should include buffer time for security screening, baggage drop, and reaching the gate. Boarding Pass Tips Mobile boarding passes are accepted at most airports in the United States and many international destinations. These will update automatically if your gate changes. Paper boarding passes can still be printed at airport kiosks or counters. Some travelers prefer having a paper copy as a backup. What to Do if You Miss the Online Check-In Window If you miss the online or mobile check-in cut-off: Try checking in at a self-service kiosk (if time permits). If the kiosk does not allow check-in, go directly to the ticket counter or gate desk. Be aware that if you're past the 45-minute (domestic) or 60-minute (international) cutoff, you may be denied boarding.