United’s Cancellation Policy: Flights Paid With Cash or Points
All customers have 24 hours from the time of their original booking to cancel their reservation without being charged a cancellation fee, regardless of the fare selected, as long as the ticket was purchased a week or more before departure.
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Non-Refundable Ticket
If it has been more than 24 hours since you booked your ticket, you can still cancel your ticket and get a full refund, but it will come in the form of a flight credit toward future travel with United