Mastercard cards will keep working when the power is out or the network is down. The service will start in 2027 in several European countries, including Bulgaria, the company said.
Payments will go through with chip and PIN, even during an outage. A single offline purchase can be no more than €200.
"When there is a power or network outage, people still need to buy food, fuel and medicine," said Bryce van de Vale, executive vice president for core payments at Mastercard Europe.
The bank that issued the card sets in advance how much can be spent offline. The limit is stored securely in the chip. If the shop terminal loses its connection, it approves the payment on the spot. Once the connection is back, the payment goes through clearing, where banks settle it for good.
People will be able to pay offline in supermarkets, grocery shops, petrol stations, pharmacies and ticket machines.
All new Mastercard cards issued in Europe will have this feature from February next year. New and replacement POS terminals, which shops use to accept cards, must support it by May 2027.
The company has already introduced offline payments in Denmark, Sweden, Estonia and Latvia. "We saw that offline payments can make a real difference," van de Vale said.
The service will be introduced across Europe after talks with the company's partners, national governments, regulators and central banks.
The new rules follow steps Mastercard has taken over the past 12 months: money for local infrastructure and cybersecurity, so that European payment networks cope better with outages.