RBS has admitted as many as 600,000 payments were affected by the technical glitch (Source: Getty)
RBS has failed to put through around 600,000 payments for customers across the group as a result of a technical issue - and the money could be missing for several more days.
RBS has since said it has identified and fixed the issue, and that accounts were being updated as a “priority” but it could take until Saturday for payments to go through.
Tax credits and disability living allowance are among the payments that have failed to be credited to accounts, leaving customers complaining that will be unable to pay bills or access their own money.
"We are aware of an issue with our overnight process which has resulted in some of our customers not having credits or direct debits being applied to their accounts," a spokesman for RBS
"We are working to get this resolved as quickly as possible and apologise to customers for the inconvenience caused.
"To any customers concerned about the implications of this issue, we advise them to get in touch with our call centres or come into a branch where our staff will be ready to help. We will ensure no customers are left out of pocket as a result of this issue."
Customers were furious, however, with many complaining that they had been left on the premium phone line for as long as an hour.
Others said they were concerned about not being able to access their cash.
This is not the first technical hitch to affect RBS. In 2012, an IT meltdown
locked 17m customers out of their accounts for days, resulting in an estimated £175m in costs and compensation and an investigation by the FCA.
And ahead of Christmas in 2013, consumers were left unable to make purchases on Cyber Monday - the busiest shopping day of the year.
RBS' share price was down 0.4 per cent at pixel time.