Customers are furious with BNZ after hours of trying and failing to use their mobile and online banking service.
The problems started early on Saturday morning and continued into the early evening, leaving customers without online hours for more than five hours.
One Herald reporter was able to access their mobile but not online banking about 5pm.
Many customers said on the bank's social media pages they felt outages for the mobile and online banking systems were too common.
"BNZ Mobile App down — again," wrote Jason Belworthy on Facebook.