When you submit a reservation request on Airbnb (that isn't "Instant Book"), the host has exactly 24 hours to officially accept or decline. If they do not take action within this window, the request automatically expires. If it expires, you are not charged, and any temporary authorization hold on your payment method will be released. In 2026, Airbnb encourages hosts to respond quickly, but if a host remains unresponsive, your best move is to message other hosts or look for listings with the Instant Book lightning bolt icon to ensure an immediate confirmation. If you had a confirmed booking and the host stops responding to check-in messages, you should contact Airbnb Support to assist with a rebooking or refund.