NAB is refunding $25 million to more than 62,000 of its wealth customers following a glitch on its Navigator Wrap platform.

The internal systems error, dating back to 2001, meant that money was withheld on the platform and clients were not paid all the money they were owed.

According to Fairfax, the bank is expected to pay each customer an average of $400, including interest, with 75% of customers receiving a payment of up to $350 plus interest.

The problem was discovered last year when the corporate watchdog, Australian Securities and Investments Commission (ASIC), ordered NAB to undertake an audit following previous errors where the bank was forced to pay back $1.9 million in compensation to 43,000 customers.

“Our teams have worked extensively, with oversight by PwC and ASIC, to ensure the right processes, systems and controls are now in place,” NAB Wealth and MLC group executive Andrew Haggar told The Australian.

“While this is a legacy issue, we took deliberate steps to make ­absolutely sure we could get the fairest outcome for our customers.”

The bank is now in the process of crediting the accounts saying at “no stage have these monies been held by, or accounted for, as part of the assets of any NAB Group company”.

Earlier this year, ANZ gave back $30 million after 8,500 customers failed to receive annual review documentation they had paid for.

Read more here.

Follow Business Insider Australia on Facebook, Twitter, and LinkedIn