Those behind the class action against ANZ Bank over penalty fees say thousands of aggrieved bank customers rushed to sign up following Tuesday's announcement that court documents will be filed early next week.
Fair Play on Fees lawyer Andrew Hooker said more than 3000 ANZ customers had registered for the class action in the past 24 hours. The deadline is 25 June.
Mr Hooker said this surge in interest takes registrations to more than 28,000 since the campaign launched in March, and the number of ANZ customers involved to about 14,000.
They are seeking to recoup money unfairly charged by the bank as default fees.
Mr Hooker said people are sick of these fees because they know that they're unfair.
The Fair Play on Fees legal team has called on ANZ to provide evidence its bank fees reflect the cost of the transactions after the bank claimed it had done extensive analysis on its fee structure.
ANZ has said it will vigourously defend the claims.