Royal Bank of Scotland (RBS), Ulster Bank and Natwest's online banking services were down for around three hours this morning, leaving millions of users without digital access to their accounts.
Natwest’s mobile app couldn't establish a connection, and referred users to an online status page, which failed to open, a problem shared by Ulster and the two consumer banks' parent bank, RBS.
RBS boss Ross McEwan told LBC this morning that he didn't know what caused the outage.
"We're still working through what the issue is. We make a lot of changes to our technology on an ongoing basis, it may be related to that, but we just don't know at this point," he admitted.
Customers were left to vent their anger on Twitter.
@NatWest_Help can you please sort your app and Web out need to transfer money before work— beth (@mick1743) September 21, 2018
@NatWest_Help is the banking app having difficulties? I can't get on. Says it's my internet connection but tried 3 different internet places and same result. Internet my end is consistent.— Corinne (@corinnecherry) September 21, 2018
The problems at Natwest appear to have started at around 7am, but they were fixed around 10am, with RBS confirming all three banks' services are back online.
“We would like to apologise to customers who experienced issues logging into their online and mobile banking accounts this morning, this issue has now being resolved," a spokesperson said.
It comes after City A.M. yesterday reported that Barclays faces a Treasury Select Committee investigation into a failure that saw customers unable to use its online banking services for six hours earlier this week.
The committee also investigated TSB’s ongoing problems affecting millions of users for weeks on end after a botched IT migration forced it to call in IBM to help put things right.
Chief executive Paul Pester ended up stepping down following the crisis, with the bank insisting it has a plan to improve services as an investigation into the problems is fast-tracked.