Not everyone is cheering. Sweden's embrace of electronic payments has alarmed consumer organisations and critics who warn of a rising threat to privacy and increased vulnerability to sophisticated Internet crimes. Electronic fraud cases surge Last year, the number of electronic fraud cases surged to 140,000, more than double the amount a decade ago, according to Sweden's Ministry of Justice. Older adults and refugees in Sweden who use cash may be marginalised, critics say. And young people who use apps to pay for everything or take out loans via their mobile phones risk falling into debt. "It might be trendy," said Bjorn Eriksson, a former director of the Swedish police force and former president of Interpol. "But there are all sorts of risks when a society starts to go cashless."

But advocates like Ulvaeus cite personal safety as a reason that countries should go cash-free. He switched to using only card and electronic payments after his son's Stockholm apartment was burglarised twice several years ago. "There was such a feeling of insecurity," said Ulvaeus, who carries no cash at all. "It made me think: What would happen if this was a cashless society, and the robbers couldn't sell what they stole?" Bills and coins now represent just 2 per cent of Sweden's economy, compared with 7.7 per cent in the United States and 10 per cent in the euro area. This year, only a fifth of all consumer payments in Sweden have been made in cash, compared with an average of 75 per cent in the rest of the world, according to Euromonitor International. Cards are still king in Sweden with nearly 2.4 billion credit and debit transactions in 2013, compared with 213 million 15 years earlier. But even plastic is facing competition, as a rising number of Swedes use apps for everyday commerce. Cash not accepted

At more than half of the branches of the country's biggest banks, including SEB, Swedbank, Nordea Bank and others, no cash is kept on hand, nor are cash deposits accepted. They say they are saving a significant amount on security by removing the incentive for bank robberies. Last year, Swedish bank vaults held around 3.6 billion krona in notes and coins, down from 8.7 billion in 2010, according to the Bank for International Settlements. Cash machines, which are controlled by a Swedish bank consortium, are being dismantled by the hundreds, especially in rural areas. Eriksson, who now heads the Association of Swedish Private Security Companies, a lobbying group for firms providing security for cash transfers, accuses banks and credit card companies of trying to "price cash out of the market" to make way for cards and electronic payments, which generate fee income. "I don't think that's something they should decide on their own," he said. "Should they really be able to use their market force to turn Sweden into a cashless society?" The government has not sought to stem the cashless tide. If anything, it has benefited from more efficient tax collection, because electronic transactions leave a trail; in countries like Greece and Italy, where cash is still heavily used, tax evasion remains a big problem.

Leif Trogen, an official at the Swedish Bankers' Association, acknowledged that banks were earning substantial fee income from the cashless revolution. But because it costs money for banks and businesses to conduct commerce in cash, reducing its use makes financial sense, Trogen said. Cash is certainly not dead. The Swedish central bank, the Riksbank, predicts it will decline fast but still be circulating in 20 years. Stefan Wikberg, 65, was homeless for four years after losing his job as an IT technician. He sells magazines for Situation Stockholm, a charitable organisation, and began using a mobile card reader to take payments, after noticing that almost no one carried cash. "Now people can't get away," said Wikberg.

"When they say, 'I don't have change,' I tell them they can pay with card or even by SMS," he said. His sales have grown by 30 percent since he adopted the card reader two years ago. At the Filadelfia Stockholm church, so few of the 1,000 parishioners now carry cash that the church had to adapt, said Soren Eskilsson, the executive pastor. During a recent Sunday service, the church's bank account number was projected onto a large screen. Worshippers pulled out cell phones and tithed through an app called Swish, a payment system set up by Sweden's biggest banks that is fast becoming a rival to cards. Last year, out of 20 million krona in tithes collected, more than 85 percent came in by card or digital payment. "People give more money to the church now because it's electronic and easy," said Eskilsson, adding that the church saved on security costs by handling less cash.

Despite the convenience, even some who stand to gain from a cashless society see drawbacks. "Big Brother can watch exactly what you're doing if you purchase things only electronically," said Jacob de Geer, a founder of iZette, which makes a mobile-powered card reader. But for Ulvaeus, the music magnate, such concerns are overblown. "Everything speaks in favor of a cashless society," he said as he strolled past the Abba Museum to retrieve his car. "It's a utopian thought, but we're very close to it." He paused at a hot-dog stand for a snack. But when he was ready to pay, the card reader was broken.

"Sorry," the vendor said. "You'll have to use cash." - NEW YORK TIMES