When can passengers check in online for United Airlines flights?

Passengers can check in online for United Airlines flights up to 24 hours before the scheduled departure time. This policy allows travelers ample time to review their flight information, make changes if necessary, and secure their boarding passes in advance. Online check-in enhances the travel experience by enabling passengers to select their seats, avoid long lines at the airport, and streamline the check-in process, facilitating a smoother journey.

The options reflecting shorter check-in periods do not align with United Airlines' policy, which specifies a 24-hour window for online check-in. Moreover, allowing check-in only the night before departure restricts flexibility for travelers who might need to finalize their travel arrangements earlier. Therefore, the 24-hour timeframe offers a balance between convenience and allowing sufficient time for any necessary preparations before a flight.