A judge has ordered ten financial institutions to pay more than $200 million to credit-card holders who were overcharged on currency-conversion fees.

The customers had used their cards outside Canada, mainly in the United States, from 1993 to 2003.

Quebec Superior Court Justice Clement Gascon ruled on three separate class-action lawsuits at the Montreal courthouse on Thursday.

The banks, credit-card companies and Caisse Desjardins have 30 days to appeal and it's not clear when customers will get their money back.

However, the Option Consommateurs consumers' group said the ruling still speaks volumes.

"It is a very important decision," said the group's lawyer, Stephanie Poulin.

"It confirms that the Consumer Protection Act applies to the banks and various financial institutions. They cannot use the argument that they are (under) federal jurisdiction to avoid respecting the law."

The institutions that lost in court also include the Royal Bank, the National Bank, Toronto Dominion and American Express.