The Commerce Commission said there had been multiple errors in Kiwibank's manual and electronic systems. Photo: RNZ / Marika Khabazi
Kiwibank says it is sorry for errors resulting in more than 36,000 customers being overcharged by $7 million.
Kiwibank confirmed it reported breaches of the Fair Trading Act to the Commerce Commission, which had resulted in 21 criminal charges.
The charges related to overcharged fees and interest rates on home loans, credit cards and overdrafts since 2019, but the commission said there had been problems since Kiwibank was established in 2002.
Commerce Commission deputy chairperson Anne Callinan said these were serious charges, stemming from multiple errors in Kiwibank's manual and electronic systems which resulted in the bank misrepresenting what customers owed.
"In the Commission's view these are longstanding, systemic breaches of the Fair Trading Act some of which date back to Kiwibank's inception in 2002," Callinan said, adding the charges related specifically to overcharges from 2019.
"Lenders must have processes in place to ensure consumers are getting a fair deal and are charged what was advertised to them," she said.
"The commission expects banks to make the necessary investment in the systems that support their compliance obligations so they get things right for consumers."
The bank reported the overcharges to the commission and had been contacting affected customers and progressively refunding overcharges.
The commission said it could not comment further with the case before the court.