It's also important when you cancel your flight: if it's within 24 hours of booking, the fees will be lower. If, on the other hand, you decide you don't want your ticket shortly before departure or don't show up at the airport, then according to qantas airways cancellation policy, you'll have to pay a higher price. You will receive a refund, but the refund amount will be the original price you paid minus any fees deducted.