How Debit Card Processing Works
You’re familiar with the basics—you walk up to an automated teller machine, insert your card, punch in your PIN, ask for cash and (provided you have some in your account) you get your money. On the other hand, perhaps you don’t have any cash in your wallet and you want to make a purchase. So long as you’ve got the cash in your account, you’re good to go. You swipe your card at the terminal just like a credit card, maybe enter your PIN, and the purchase is made. It all seems very easy, but what is the debit card payment process? How does the transaction go from point of sale to your bank and back?
There are two forms of debit card payment process. These are the offline, signature-based process, and the online, PIN-based process.
Offline cards have to be branded as VISA or MasterCard, and are processed in a similar manner to credit cards. That is, the vendor’s equipment connects to a payment network, sends the request from the card, and waits while the network performs a series of tests to ensure that the card is not authorized for use, frozen, over the limit (or overdrawn, in the case of the debit card). This whole process generally only takes a few seconds. If the request is approved, you will sign the receipt, at which point the vendor puts the request into a payment batch and goes through a settlement process at the close of the business day to get the money. This can take 48 to 72 hours.
For the online debit card payment process, you will swipe your card and be asked to enter your PIN, which substitutes for your signature. In many cases, you will in this type of transaction have the option to get cash back. Since you have used your PIN, by the time the sales information gets to your financial institution, the transaction itself is already authorized by you, so no authorization check is performed. Similar to the offline method, the connection and communication with the network takes mere seconds to perform. As long as there is enough money to cover the sale in your account, the transaction will be approved. Unlike the offline method, your checking account will immediately be debited—there is no waiting period for processing, and funds are transferred instantly from your account to the vendor’s.