Most small and medium businesses don’t accept payment via credit or debit cards, something which is costing them £7.5 billion a year, according to Barclays.

A study by the bank shows that while nearly three-quarters of retail transactions take place using cards, only 42 per cent of shops accepts them.

A quarter of those answering the study admitted it had cost them opportunities with customers going elsewhere.

“For any business, the challenge is to first secure customers' interest and then to convert the interest into sales,” said Philip McHugh, chief executive of Barclaycard Business Solutions.

“However, our research has shown that many small businesses are falling at the final hurdle and losing customers and vital revenue by not accepting card payments.”

Perceived high costs and fears over complicated processes were the chief factors putting off retailers, according to the study.