If a ticket is canceled within 24 hours of purchase by United Airlines, full refunds will be issued, provided that the reservation was made at least 7 days in advance of the departure date. This holds for all reservation kinds, even tickets for Basic Economy.
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To make and manage reservations using the website or mobile application, consult United Airlines Reservations. If you cancel your ticket within the 24-hour window, as per United's cancellation policy, your refund will be issued back to the original payment method.