Payments NZ, which manages overnight payments between banks through its Swift network, says a computer glitch hit its system at 2am this morning.
The problem - caused by a single faulty jumper cable - affected all New Zealand banks, and meant payments - including thousands of wages and salaries - did not go through.
Payments NZ CEO Steve Nichols said that the fault was fixed, but it would take time to sort out all payments.
“Experts from all banks have been working throughout the night to clear the backlog of payments. Some payments have been processed already and we expect that everything will be back to normal soon.”
Most payments had been put through by around 1.30pm.
Although tens of thousands were affected, a recent move from single overnight payments to banks exchanging payments five times a day limited the scope of the problem.