The IT errors that affected some Nationwide and NatWest customers yesterday have been fixed.
NatWest customers, part of the Royal Bank of Scotland (RBS) banking group had problems with debit card transactions.
And more than 700,000 Nationwide customers saw debit payments and purchases taken twice causing some of them to go overdrawn.
Last night a spokesman for RBS said: "Online banking is now fully operational and debit card transactions are processing as normal. We continue to monitor the systems closely and will keep our customers fully informed. We apologise for any inconvenience caused."
Meanwhile, Nationwide says that just 50,000 of the total of 700,000 people were adversely affected through wrongly incurring charges or fees by the problem that was caused by a “human error.”
Jenny Groves, from Nationwide Building Society said: "Nationwide wishes to apologise to those customers affected by an issue which has affected some of our debit card customers.
"A small number of customers will have been adversely impacted. All charges will be refunded in full and any costs associated with this error will be reimbursed in full. None of our customers will suffer financial loss as a result of this one-off error.”
Nationwide has been a beneficiary of the banking crisis, seeing a 45 per cent increase in new customers looking to switch after the IT errors that affected millions of NatWest customers in June.
Yesterday’s glitch will damage the building society’s reputation to some extent as it tries to market itself as offering something different from the big banks, though the fact that the errors have been corrected quickly will help minimise the impact.
Richard Lloyd, executive director of consumer body Which?, said: "This again raises wider questions about how robust banks' systems and safeguards are as consumers bear the brunt of yet another banking glitch.
"The least Nationwide can do is keep their customers properly informed on the issue and we think they should compensate those people who have been seriously affected."
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