Travelers can view their flight reservation numbers online by printing their boarding passes at www.united.com. You can also print your boarding pass at the airport. You can also print your boarding pass at any airport kiosk to verify your reservation number.

Email confirmation
United Airlines passengers who book online flights will be sent confirmation emails. You can do this by visiting their website or calling United Airlines' reservations team. The email address can be used to locate the flight confirmation number.
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