A transaction that has been voided is when a credit card purchase that a seller cancels after it has been authorized but before it has been settled. A void transaction does not appear on the customer's credit card statement, though it might appear in a list of pending transactions when the customer checks their account online.
Refunds are always associated with a transaction that has settled, meaning the funds have already transferred from the customer to the merchant. ... A refunded transaction goes through the typical settlement process; as soon as the refund settles, the funds are sent back to the customer's bank account.