How long does a hold on a debit/credit card last?

How long does a hold on a debit/credit card last?

Generally holds last for up to four days but they will close if the merchant processes the debit transaction against your card earlier than the four days.
If the merchant does not process the debit within the four days, the hold will close automatically and the available balance in your account will be increased by the amount of the closed hold.

Even if the hold closes after four days, and your account has not been debited, the merchant can still legally take the funds for up to 180 days. Once a transaction has been granted an authorisation, or pre-authorisation, the merchant has the right to process the debit at any time within the 180 days. If the funds have been ‘re-used’ (ie. you did not continue to allow for the debit, if the ‘hold’ had closed before the debit was processed) the account may become overdrawn.