ANZ Bank experienced problems with its internet banking system this morning, leaving some customers unable to log on.

Customers began posting on the bank's Facebook page at about 9:40am, complaining about being unable to get access to the internet banking service.

"ANZ Internet banking is down again! Please can u sort it out," Caleb Hendry posted at 10:30am.

An ANZ spokesman said a small number of customers were unable to log on to internet banking for about 20 minutes this morning.


The issue had now been resolved but some customers may need to refresh their browsers, he said.

The country's largest bank has experienced a series of problems with its technology this year.

On August 11, it suffered intermittent outages to its Eftpos services, leaving many shoppers around the country unable to make purchases.

Some customers later found they had been charged multiple times for the same transaction and many turning to social media for answers.

In mid-April, a glitch caused overnight payments to be held up and denied ANZ customers of access to internet banking.

On January 31, a nationwide fault left many of the bank's customers unable to use their credit and direct debit cards over lunchtime.

ANZ says the problems have nothing to do with its technology merger with National Bank last October.