Originally Posted by
josephstern
Yes - any merchant that does "Pre-authorization and capture" as two separate transactions can easily void the pre-authorization any time they want. It may take a few days for your bank to process that, but from the merchant's standpoint, it's immediate.
Now, the operator may not have had access to that level for financial transactions . . .
Visa's systems allows a merchant to go back and process an authorization reversal (for any amount up to the full amount of the transaction), which should instantly give back the amount released into the cardholder's available credit.
MasterCard, American Express, Discover, and Diner's Club (if any still exist that are not rebranded to MasterCard) do not have that capability, and voiding an authorization will involve the merchant calling or faxing the cardholder's bank to manually request the authorization be voided.
I typed up a rather long explanation of how this all works on another forum. That post (plus the four posts following that which further explain the process, including reversals) can be viewed
here.