When using a debit card for a purchase, the transaction works as follows:
1. Card swipe or entry: The cardholder presents the debit card to the merchant either by swiping it through the card reader or by providing the card details manually.
2. Merchant authorization: The merchant sends a request to the cardholder's bank or payment processor to verify if sufficient funds are available in the linked bank account to cover the purchase.
3. Bank approval: The cardholder's bank receives the authorization request and checks if there are enough funds in the linked checking account. If approved, the bank sets aside the necessary funds for the purchase.
4. Purchase completion: If the bank approves the transaction, the merchant is notified, and the sale is completed. The cardholder receives the goods or services, and the merchant can proceed with the transaction.
5. Payment settlement: The bank sends the payment records to the merchant's acquiring bank, and the amount spent is transferred from the cardholder's bank account to the merchant's account.
It's important to note that with a debit card, the funds are typically deducted immediately or within a few days from the cardholder's checking account, ensuring that the user spends only the available funds within their account. Unlike a credit card, which allows borrowing money from the card issuer, a debit card only allows spending the money that is already available in the cardholder's linked bank account.