An authorization hold is when your bank "holds" the balance of a debit or credit card transaction until the merchant clears the transaction or the hold "falls off," making the balance available to you again.
Authorization holds on debit cards
With debit cards, authorization holds (also known as card authorization, pre-authorization, or pre-auth) can fall off the account anywhere from 1–10 days after the transaction date depending on your bank's policy.
Authorization holds on credit cards
With credit cards, authorization holds may last as long as 30 days, depending on the issuing bank's policy.