With the support of litigation funder Bentham IMF, the lawsuits were filed against Westpac, St.George, Citibank, Bank of South Australia (BankSA) and Australia and New Zealand Banking Group (ANZ).
The class action is likely to be worth millions of dollars and builds on the success of a previous case against ANZ in the Federal Court of Australia in February.
Maurice Blackburn class action practice head Andrew Watson said the affected consumers will have a right to access some compensation for those unfair charges, if the class actions prevail.
"Our case is based on the earlier Federal Court ruling against ANZ. Whilst that judgment is under appeal we think we have a very strong case and that this course of action provides the best safeguard for the rights of all those consumers affected by late fees.
"What we’re doing today opens the gates of justice to millions more Australians and means that previous estimates of the numbers of people affected and the compensation amounts owed will be dwarfed by the new state of play."
Bentham IMF investment manager and Client Group head James Middleweek said the filing of the open class will include a common fund application.
"It is clearly evident from this case that the class action regime in Australia – backed by litigation funding – is the only genuinely effective vehicle to offer commercial redress to people that are subjected to corporate wrongdoing in this way."
Maurice Blackburn plans to file similar lawsuits against American Express, the Commonwealth Bank, the National Australia Bank (NAB) and BankWest.
The law firm estimates the banks charged Australian households, exclusing businesses, A$652m ($604m) in exception fees between June 2009 to July 2010.
Image: Westpac is one of the five Australian banks charged by Maurice Blackburn over late bank fees charges. Photo: courtesy of Merbabu.
