British banks may be raking in the profits but their online customer service has sunk to an all time low, according to the latest research.

Transversal, an eService provider, said in its annual report that half of the major high street banks surveyed were unable to answer a single one of the most basic questions emailed to them by the company.

Overall the banks could only answer on average a quarter of what Transversal called the ten common questions the survey asked.

These questions were based on typical customer enquiries and asked for information on credit card offers, borrowing and mortgages.

To add insult to injury, although banks are pushing customers towards online banking because of branch closures, sixty per cent of bank websites didn't allow consumers to contact them via email.

This means customers are having to phone call contact centres, which are often pushed offshore, dramatically increasing frustration.

Of those that provided the ability to email, they took a laggardly average of 22 hours to respond. Even the shortest response took eight hours, which is the equivalent of a whole business day.

The slowest response was 69 hours - sufficient time to travel to an offshored contact centre and ask the question in person.

Transversal said its findings showed things are substantially worse than in 2005, when only two banks scored zero and the sector successfully answered three questions on average.

The results the company said demonstrate that banks are failing to take online service seriously, despite research by Alliance & Leicester showing 56 per cent of Britons now bank on the web

"The immediacy and speed of the online channel suits both consumers and banks, but must be backed up by fast, accurate customer service" commented Davin Yap, CEO, Transversal.

"While more and more Britons are banking online overall customer service has taken a dramatic step backward over the last year. Our research shows a growing chasm between the best and worst performers.

The Financial Ombudsman Service said it hadn't any reports that would indicate that banks' online customer services were necessarily that poor. But it said anyone who had a problem with a British bank could always contact it for advice and help .