You have the option of changing your travel plans or canceling your flight. If you cancel within 24 hours of your booking, you will receive a full refund. Reservations must be made at least one week before your scheduled departure date to qualify for Jetstar's 24-hour cancellation window. Jetstar 24 hour cancellation policy is intended to give you flexibility and assurance, with no fees if you need to change your plans quickly after booking. Please keep in mind that if you cancel your flight after 24 hours or less than a week before departure, different restrictions and conditions will apply.
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Jetstar Cancellation Policy

Jetstar Cancellation Policy Overview| +61 (1800) 407 707