Travel plans may change, and you need to cancel your existing reservation. Aer Lingus Cancellation Policy allows you to cancel your flights within 24 hours of the booking time to receive a full refund. If you exceed this window, you have to pay a cancellation fee. For refundable tickets, the amount will be refunded in the original form of payment. Whereas for non-refundable tickets, Aer Lingus will provide a refund as a travel voucher or credits.