Commission to investigate Kiwibank

The Commerce Commission has decided to investigate a complaint made by Wizard Home Loans against Kiwibank's mortgage guarantee.

State-owned Kiwibank last month launched an advertising campaign where it guaranteed that its mortgage deals would be better than those of the big five banks over the next six years.

If the customer proved that was possible then Kiwibank would refund the difference.

Wizard complained to the Commerce Commission alleging that the ad was misleading.

The commission has decided to investigate the complainant but won't say how long that process will take.