What happens depends entirely on the "Cancellation Policy" of the specific property you booked. Booking.com is a marketplace, not the hotel itself. If you booked a "Free Cancellation" rate, you can cancel via the app or website up to the deadline (usually 24–48 hours before check-in) and receive a full refund. If you booked a "Non-Refundable" rate, you will lose the entire amount regardless of how early you cancel. In 2026, Booking.com has introduced "Booking.com Protected" in some regions, which allows for more flexible cancellations for a small fee. If you cancel a "Pay at Hotel" booking after the deadline, the hotel will charge the credit card you provided as a "No-Show" fee, typically the cost of the first night. Always take a screenshot of your cancellation confirmation, as technical glitches can occasionally lead to disputed charges.