By 4pm, the services were still not working.
“Apologies to our customers who can’t access Internet Banking & the Mobile App at the moment – we’re working to fix this ASAP. You can still access ATMs, EFTPOS facilities and branch services as usual,” the NAB account posted on Twitter just before 3pm.
The bank says they are investigating the source of the outage and are unsure when the services will be back up and running.
On social media, NAB customers complained of the outage, with some saying they had planned to carry out large transactions or were about to pay wages to their employees on Friday but were unable to.
“It’s been hours,” one Twitter user, Jackie Bolsonaro wrote.
“We gave up and will try again later. I needed to make a simple transfer and it turned out to be a big deal.”
A NAB spokeswoman said the bank was working to fix the issue as soon as possible.
“NAB internet banking and mobile banking are currently unavailable. Our teams are working to restore services as quickly as possible and we are sorry for the inconvenience. Customers can access ATMs, EFTPOS facilities and branch services as usual,” she said.