Lloyds Banking Group customers were unable to access online accounts for an hour on Monday afternoon due to an IT failure.
Customers of Lloyds and Halifax reported problems with internet services yesterday, prompting an apology from the group which claims the systems are now fully functioning.
"For an hour yesterday afternoon, we experienced an issue that affected some of our online banking customers," a spokesperson told ComputerworldUK.
"All of our systems were back up and running by 5pm. We know our customers rely on us, and we apologise for the inconvenience we have caused them."
However, Lloyds declined to comment on the nature of the fault which led to customer experiencing problems.
Lloyds customers have been affected by a number of IT issues in recent months. A systems failure meant that customers were unable to access accounts hours ahead of New Year's Eve, leaving many unable to withdraw cash from ATMs or pay by debit card.
In January a routine update of customer data stopped the transfer of funds using the Faster Payments service, blocking Lloyds customers from accessing payments for a number of hours.
Twitter users reported problems with the site, with one highlighting initial claims by the bank that the outage followed updates being made to the site.
Telegraph finance editor Simon Read (@simonnread18h) said: "Lloyds online banking is down because of "essential changes on the site". Customers simply told "Please try again later."
There have been numerous cases of systems failures at high street banks, largely blamed on the legacy systems owned by many UK banks.
Newly formed regulator, the Financial Conduct Authority (FCA), announced this month that it would begin an investigation into the IT system failure which lasted over a month last year, affecting millions of Natwest and Ulster Bank customers