Turkish Airlines' cancellation policy allows passengers to cancel their flights, but the conditions depend on the fare type and ticket rules. Refundable tickets typically offer full refunds, while non-refundable tickets may result in a partial refund or no refund at all. In case of a flight cancellation by the airline, passengers are entitled to a full refund or rebooking. Turkish Airlines also offers the option to change the date of the flight, often for a fee. It's advisable to check specific ticket conditions and contact customer service for more details regarding cancellations or changes.