The cashless society could soon be reality in Sweden, where four in five purchases are now made electronically or with payment cards, and new technology and mobile applications are developing rapidly.

“Sweden and the other Nordic countries are world leaders when it comes to cash-free trade,” Bengt Nilervall of the Swedish Trade Federation told news agency TT.

Swedes use debit and credit cards more or less on a daily basis, with an average of 260 transactions per person per year.

More and more street vendors have started accepting card payments, too. In southern and western Sweden, homeless magazine vendors have even...