Stallholders at Covent Garden's arts and craft market in central London have been equipped with mobile point-of-sale card readers supplied by PayPal, enabling them to accept debit card payments over the busy Christmas shopping period.
The move breaks with an 800-year old tradition of cash-only payments at the popular indoor market, which is expecting more than eight million visitors over the Christmas shopping season.
PayPal says the initiative marks the end of the "cashpoint dash", as traders cash in on millions of pounds' worth of sales that would otherwise be lost when cashless customers promise to return - but never actually do.
Market trader Adam Regester says: "Most people these days just don't have ready cash with them and they expect you to have a card machine of some sort. People would come to my stall, they would look at items and ask if I took cards. When I suggested they go to the nearest cash machine, often they wouldn't do that or wouldn't come back."
He says his takings shot up by 30% on the first day of using the PayPal mobile card reader.
PayPal research has shown that most people typically carry no more than £20 ready cash with them and that small businesses may be missing out on up to £800 million worth of sales every year by not taking credit and debit card payments.