Contactless Payment: How Does Tap & Pay Work, and How Is Money Deducted When You Hold Your Card Near a Payment Machine?

Contactless Payment System: Have you ever wondered how, while shopping, money is deducted in a second—without even inserting a PIN—just by bringing your card close to the payment machine? Learn about the technology that makes this possible.

Contactless Payment System: As technology advances, the way people go about their daily tasks continues to evolve. Payment methods have transitioned from cash to debit and credit cards, and subsequently to UPI—making the process of paying increasingly convenient. While many have adopted UPI, some still prefer using cards. Previously, using a debit or credit card required swiping it through a machine and then entering a PIN.

Now, however, new technology allows for payments to be processed in a second simply by bringing the card near the machine. This feature is known as 'Tap & Pay,' or a contactless payment system. Many people often wonder how money can be deducted from their accounts without the card physically touching the machine or requiring a PIN. Let’s explore how this entire system works and whether your money remains secure.

How do contactless card payments work?

The technology behind the 'Tap & Pay' system is called NFC, or Near Field Communication. It functions similarly to Bluetooth or Wi-Fi, but with a much shorter range. If you look closely at your card, you might notice a small symbol that resembles a Wi-Fi icon. This indicates that the card contains an ultra-thin antenna and a tiny microchip. When a merchant enters the payment amount into the POS (Point of Sale) terminal and activates it,

the machine emits a low-power radio frequency signal in its immediate vicinity. As soon as you bring your card or an NFC-enabled phone within 2 to 4 centimeters of the machine, the antenna inside the card receives power from the machine's waves, instantly activating the chip. The card then transmits its data wirelessly to the machine, establishing a connection between the two.

How does a transaction occur without entering a PIN?

This process incorporates robust security measures to ensure that your card number cannot be stolen. The card does not transmit your 16-digit card number to the machine; instead, for every payment, it generates and sends a unique secret code—a one-time token. The machine immediately forwards this secret code to your bank's server. Within a fraction of a second, the bank's computer verifies the validity of the code and confirms whether there is a sufficient balance in your account.

If everything is in order, the bank grants approval, the machine emits a beep, and the funds are deducted. According to Reserve Bank of India (RBI) regulations, to save time, a PIN is not required for payments of up to ₹5,000. However, for transactions exceeding ₹5,000, while you may still tap your card, the payment will only be processed once you enter your PIN into the machine.

Is it possible for someone to steal money from a card kept in your pocket?

Videos often circulate on social media showing a thief carrying a payment terminal and attempting to steal money by bringing the device close to people's pockets. In reality, however, this is virtually impossible. Firstly, NFC technology only functions when the distance between the card and the machine is less than 4 centimeters and the card is positioned at the precise angle. Secondly, the presence of other cards or coins inside a wallet would effectively block the signal. Furthermore, a payment terminal is linked to a registered bank account; therefore, a thief cannot use such a device while keeping their identity hidden. Nevertheless, for your own peace of mind and complete security, you can adjust the 'Tap & Pay' limit via your bank's mobile app, or even disable the feature entirely when it is not in use.