Nationwide has apologised to customers after planned upgrades to its systems meant customers were unable to access mobile and online banking for a short period of time yesterday.
The glitch was caused as system maintenance carried out between 1pm to 3pm overran, the bank said. This resulted in online banking and mobile apps being taken offline temporarily, with customers affected for approximately 45 minutes as staff worked to restore the service. All systems have now returned to normal.
The problems did not affect ATMs, though some customers also experienced delays to payments. However, this is believed to be a minority of cases.
"We did experience an issue, we identified it and resolved as quickly as we possibly could, and we apologise for any inconvenience caused to customers," a bank spokesperson said.
Nationwide, which serves 5.5 million UK current account customers, has undergone a major overhaul of its technology in recent years, including replacing its legacy Unisys mainframe with a new SAP core banking platform in September 2013. It has continued to modernise its systems, including completing a project to improve its mobile banking services earlier this year with an enhanced website.
The outage comes as the Bank of England experienced a systems outage earlier this week in an unrelated incident. It was forced to temporarily suspend its activity on the CHAPS (Clearing House Automated Payments System) network after problems on its Real Time Gross Settlement platform.