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United's commitment:
Customers who purchase a ticket or use Mileage PlusŪ miles to book an award ticket for travel on United may cancel their reservations without penalty within 24 hours of purchase.
What this means for you:
In order to allow our customers time to investigate travel options and prices through other channels, we allow you to cancel reservations without penalty within 24 hours of your purchase.
If you booked and purchased your travel on united.com, by calling United Reservations or visiting a United ticket counter, you may be able to cancel or change your ticket online at united.com. You can also call 1-800-UNITED-1 (800-864-8331)
If you booked and purchased your ticket through a travel agent, please contact your agent for any travel changes
You may cancel and receive a refund on your original itinerary without penalty within 24 hours of ticket issuance. If you wish to change your itinerary, fees may apply. Remember, however, that fares and seats are subject to availability and may change at any time prior to purchase.