Tesco Bank customers are the latest to suffer as a result of IT problems.
At the time of going to press the bank’s customers had been unable to access their online accounts for about a day.
A spokesman for Tesco Bank said it became aware of the problems on the afternoon of Tuesday 3 February.
“Our focus at this point is trying to recover it as quickly as possible,” said the spokesman. “We are aware that some of our customers are currently unable to view their accounts in online banking. We are working hard to resolve this matter as soon as possible.
“Customers can continue to use their accounts as normal and can contact us by phone if they need any help with their account. We apologise for the inconvenience and thank customers for their patience.”
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Tesco is one of a group of companies trying to challenge the traditional banks. One of the perceived advantages for these new banks is IT.
Tesco set up its own core banking system in November 2009, when it selected an off-the-shelf system from Fiserv. Before that it shared systems with RBS.
Traditional banks have legacy systems, which date back to the 1970s in some cases. These systems were not designed to work in today’s banking environment, where technology has changed behaviour.
But last month Sainsbury's Bank, another challenger bank, experienced IT problems that left customers unable to use their credit cards for a day.
Customer cards were declined at checkouts and customers were advised to contact the bank.
A recent survey of 2,000 people by banking software supplier Fiserv, which supplies Tesco's core banking system, showed 80% of people would trust a bank if it had the right technology in place. More than half (56%) said a new bank would have an advantage over rivals if its IT was reliable.