Note that the pre-auth comes with a sunset clause. Unless the hotel converts the pre-auth funds to a charge the pre-auth is cancelled within a specified period of time and funds are unblocked from the cardholder's account. The actual length of time a merchant can maintain a lock on funds in a pre-auth varies depending on their merchant classification code (MCC code) but five days is standard. After it expires a pre-auth can only be renewed with the consent of the cardholder.