The banks and building societies, which included Nationwide, Royal Bank of Scotland and Tesco Bank, were hit by the outage due to a problem with US payments company TSYS.
This is the latest in a string of failures in the sector in recent years, and financial services firms are now under pressure from the Treasury select committee and the Financial Conduct Authority to improve their IT resilience.
Nationwide stated most customers had been unaffected by the problem and that the issue had been resolved by Monday lunchtime (August 19).
A spokesperson for TSYS said: “A hardware-related issue which impacted the service we provide some of our European clients has been resolved.
“We are continuing to monitor our systems and are working closely with our clients to ensure everything is functioning properly.”
According to FTAdviser’s sister paper the Financial Times customers from RBS began reporting problems at the start of this week and the problems continued into Tuesday.
A spokesperson from RBS apologised for any inconvenience and said the bank would ensure no customers were left out of pocket as a result.
They added: “Our third party service provider has advised that this issue, which impacted a number of credit card suppliers, was resolved last night.
“Customer credit card information is now available in our mobile app & online banking.”
A spokesperson from Nationwide said TSYS provided credit card services to the lender and that the issue was a problem “their end”.
A Tesco Bank spokesperson said: “On Monday and Tuesday, a technical issue at a third party supplier intermittently impacted credit card servicing through our mobile app, online banking and telephony channels. This issue has now been fixed.
“We are sorry for any inconvenience this caused and thank customers for their patience.”
In April, the FCA said resilience from technology failures would be one of its main focuses in its supervision of the financial services sector after Megan Butler, executive director of supervision for the regulator, said the watchdog was "deeply concerned" at the increasing number of technology outages.
At the FCA’s annual public meeting last month (July 17), Ms Butler said the number of incidents of ‘operation resilience breaks’ reported in terms of IT failings had increased 300 per cent year-on-year, adding that she expected this to be an increasing trend.
The issues surrounding banks’ financial resilience hit the headlines last year when TSB began moving its customer data from a system controlled by its former owner, Lloyds Banking Group, to a system built by its new owner, the Spanish banking group Banco Sabadell.
The new system proved unable to cope with the number of people attempting to use it and some TSB customers faced problems for months after the migration.
imogen.tew@ft.com
