What is a Debit Card?

What Is a Debit Card?

A debit card is a payment card linked directly to the cardholder's bank account. When you make a purchase with a debit card, the money is taken from your current account -- either immediately or within a day or two. Unlike a credit card, you are spending your own money rather than borrowing from the card issuer.

Debit cards are the most widely used payment method in the UK. According to UK Finance, debit cards accounted for the majority of card payments in 2024, overtaking cash and credit cards combined. They are issued by banks and building societies, and most are linked to the Visa or Mastercard networks.

How Debit Cards Work

The mechanics of a debit card transaction are similar to a credit card transaction from the merchant's perspective:

• The customer presents their card details (either by chip and PIN, contactless, online form, or over the phone)
• The merchant's payment gateway sends the transaction details to the card network
• The card network routes the request to the issuing bank
• The bank checks the account balance and approves or declines the transaction
• The approved amount is ringfenced in the customer's account (authorisation hold) and settled to the merchant within 1-3 business days

The key difference from a credit card is that the issuing bank checks the customer's actual account balance rather than their available credit limit. If the funds are not there, the transaction is declined.

Types of Debit Cards

Standard Debit Cards

Linked to a current account, these are the most common type. They work everywhere that accepts Visa or Mastercard, both in the UK and internationally. Most come with contactless capability for in-person payments under 100 GBP.

Prepaid Debit Cards

Prepaid cards function like debit cards but are not linked to a bank account. You load money onto them in advance and spend until the balance runs out. They are popular for budgeting, gifts, and situations where a traditional bank account is not available.

Business Debit Cards

Linked to a business bank account, these allow companies to make purchases and manage expenses without using a personal card or credit facility. They often come with reporting tools to help track business spending.

Debit Cards vs Credit Cards

While both can be used for the same types of purchases, there are important differences:

• Funding Debit cards draw from your bank balance; credit cards use a credit facility that you repay later
• Interest No interest on debit card purchases (you are spending your own money); credit cards charge interest on unpaid balances
• Consumer protection Credit cards offer Section 75 protection on purchases over 100 GBP, making the card issuer jointly liable with the merchant. Debit cards have chargeback rights but not Section 75
• Credit impact Debit card use does not affect your credit score; credit card usage and repayment does
• Spending limits Debit cards are limited by your account balance; credit cards by your credit limit

Debit Card Security

Debit cards use the same security features as credit cards:

• Chip and PIN EMV chip technology for in-person transactions
• Contactless NFC technology for quick low-value payments
• CVV/CVC: The three-digit security code for online and phone payments
• 3D Secure: Additional authentication for online payments
• Fraud monitoring Banks monitor transactions for suspicious patterns and may block unusual activity

One important security consideration is that debit card fraud takes money directly from your bank account, whereas credit card fraud draws on a credit facility. This means the financial impact of debit card fraud can be more immediately felt -- your actual cash is gone while the bank investigates, which can cause problems if you have bills to pay.

Debit Cards and Telephone Payments

Debit cards are commonly used for telephone payments, and from a processing perspective they work almost identically to credit cards. The customer provides their card number, expiry date, and CVV, and the transaction is processed as a card not present / MOTO transaction.

PCI DSS requirements apply equally to debit and credit card data. Whether a customer pays with a Visa debit card or a Mastercard credit card, the merchant must protect the card details to the same standard. This means that contact centres and businesses taking phone payments need the same security measures for debit card transactions as they do for credit card transactions.

Debit cards do have slightly different characteristics for telephone payments. Authorisation holds may appear differently in the customer's account (as a pending transaction that reduces their available balance), and some banks apply lower daily transaction limits for debit cards in card not present environments. Merchants should also be aware that debit card interchange fees are typically lower than credit card interchange fees, which can affect processing costs.

For businesses taking a high volume of telephone payments, debit cards often represent the majority of transactions. Ensuring that the payment process is smooth, secure, and compliant for debit card holders is essential to maintaining customer satisfaction and protecting revenue.