Some Montreal taxi drivers are charging clients a $1 fee for using debit cards — a practise that's clearly illegal.

According to the Office de la protection du consommateur Québec, any merchants operating in Quebec are prohibited from charging additional fees. “Fees cannot be added to the price of a product or a service at the time of purchase,” reads the office’s website.

But hundreds of cab drivers are charging clients the fee.

Edgar El-Kalaani of the Montreal Taxi Owners Group told CBC Daybreak host Mike Finnerty on Wednesday that many cab drivers weren’t aware of the fee.

“Not even taxi drivers know this $1 [fee] exists,” he said.

He said the charge is legal in other provinces, and so debit card-processing machines for taxis produced in Ontario, for example, come pre-loaded with the fee attached.

El-Kalaani said cab drivers have no control over the installation or functioning of the rented machines.

But Aref Salem, the person responsible for transportation on the City of Montreal’s executive committee, said cab companies should know it’s illegal because a note was sent out in December saying so.

“It’s against Quebec law, and it’s against the regulations in Montreal,” Salem said. “All the dispatchers know already that it’s illegal.”

Cab drivers in Montreal caught charging additional fees for using debit cards face $125 fines.

Salem said taxi passengers in Montreal who have been charged additional fees for using cards as payment should report it to the City of Montreal's taxi bureau.