Danske Bank customers have been affected by technical issues with a number of their computerised services.
The bank's ATMs, website, online and mobile banking and other payment systems have been temporarily disrupted.
Customers were first notified of IT problems at around half past four on Wednesday afternoon.
In a statement, the company apologised to customers for any inconvenience and said they were "working hard to get everything back up and running as quickly as possible".
They also said customers can continue to use their cards at non-Danske Bank ATMs "and for some point-of-sale transactions".