Bank reported its own error to the Commerce Commission.
TSB Bank will refund its customers' overcharged fees after reporting itself to the Commerce Commission.
Three errors led to TSB wrongly calculating break fees for fixed-term loans between 2008 and February 2016.
The bank says it will contact customers who are entitled to a refund by the end of January. However, those charged a break fee of less than $400 between 1 October 2008 and 28 February 2013 will need to contact TSB and ask if they are entitled to a refund.
TSB reported its error as a potential breach of the Credit Contracts and Consumer Finance Act to the commission in April 2016.