ANZ has been forced to refund 25,000 customers approximately $5 million after it failed to properly apply some fee reductions and fee waivers.

Customers who held an ANZ Access Basic account, an ANZ consumer credit card or ANZ Everyday Visa Debit Card since 2007 will be refunded after the regulator revealed the breakdown in internal communications this week.

The failure arose as a result of breakdowns in the interaction between automated and manual processes, and in particular, the lack of reliability of some manual processes and controls.

ANZ says it has implemented a permanent automated solution with a system-based automated waiver, eliminating the need for manual intervention.

An Access Basic account is available to customers that meet certain criteria which include holding a Seniors Concession card, Pensioner Concession card, Centrelink Health Care card or a Repatriation Health card.

“ANZ's Access Basic account is specifically designed for low income consumers who are unable to pay high fees. This matter highlights the importance of appropriately managing manual processes to apply fee waivers and discounts, and designing and maintaining robust systems to support such features,” ASIC Deputy Chairman Peter Kell said.

ANZ is contacting affected customers to explain the error and the reimbursement and intends to complete the remediation process by the end of April 2016.