The IT failure, which occurred in June 2012, affected 6.5 million customers of NatWest, Ulster Bank and Royal Bank of Scotland for “several weeks”.
The Financial Conduct Authority, which fined the RBS Group £42m, said it had taken the action against the banks for “failing to put in place resilient IT systems which could withstand, or minimise the risk of, IT failures”.
Tracey McDermott, director of enforcement and financial crime at the FCA said: “Modern banking depends on effective, reliable and resilient IT systems. The Banks' failures meant millions of customers were unable to carry out the banking transactions which keep businesses and people's everyday lives moving.”
Over the course of that period customers could not use online banking facilities to access their accounts or obtain accurate account balances from ATMs; customers were unable to make timely mortgage payments; customers were left without cash in foreign countries; the banks applied incorrect credit and debit interest to customers’ accounts and produced inaccurate bank statements; and some organisations were unable to meet their payroll commitments or finalise their audited accounts.
In addition, the Prudential Regulation Authority fined the banks £14m. It is the first time the two authorities have taken joint enforcement action.
Meanwhile, the US Justice Department raked in $24bn (£15bn) this year in bank fines, tripling its income from these charges this year.
The haul includes JPM Morgan and Citi which made $13bn and $7bn settlements respectively over mortgage sales before the financial crisis.
