KLM’s 24-hour rule allows passengers to cancel or make changes to their flight booking within 24 hours of purchasing the ticket without incurring any cancellation fees, provided the flight is booked at least seven days before departure. This rule applies to all types of tickets, including non-refundable ones, and is in line with the U.S. Department of Transportation regulations, offering customers a window to reconsider their travel plans. If the booking is canceled within this period, KLM will issue a full refund, though this policy does not apply if the departure is within a week or if the booking is made through third-party agencies. It’s advisable to confirm all details with KLM directly, as policies may vary based on specific circumstances.