The Federal Court has handed a partial victory to ANZ customers joined in a class action to recoup $57 million in fees.

Law firm Maurice Blackburn had argued on behalf of more than 43,000 ANZ customers that fees charged by the bank over a six-year period were unfair and constituted a penalty.

This morning, the Federal Court ruled that late payment fees were illegal, but other fees were not.

The action, which began in September 2010, was the first of a series of bank-fee class actions against a total of eight banks.

The fees include honour and dishonour fees on bank accounts, over-limit fees, and late payment fees on credit cards.

Maurice Blackburn argued that charging the exception fees was unconscionable, unfair and unjust.

The lawyers claimed the bank charged exorbitant fees of $20-$45 for services that cost them only a few cents or a few dollars to administer.

The class actions are funded by publicly listed litigator Bentham IMF Australia.

In 2012, a High Court decision paved the way for the trial in the Federal Court.

ANZ did not comment during the case, other than to say it would vigorously defend itself.

Maurice Blackburn has also issued proceedings against Citibank, Commonwealth Bank, National Australia Bank, Westpac, St George, Bank SA and BankWest.

Last week, ANZ said it was refunding roughly $70 million to about 235,000 of its home loan customers after overcharging them for interest repayments.