You can’t find much information on the internet but there was a settlement in a class action suit for the benefit of Canadian Merchants. As most merchants know Visa and MasterCard do not allow merchants to charge a fee for accepting credit cards, they can however give a discount for cash or debit transactions. According to the terms of the settlement Visa and MasterCard will now allow merchants to charge a fee for accepting credit cards. Merchants will be allowed to charge a surcharge but there will be limits and merchants must disclose the charge to customers.
Merchants are currently allowed to apply a surcharge to debit transactions but few take advantage, generally they have charged in small retail outlets with small average sales. The fees for credit cards vary by card type and how they are accepted. The links below show the Interchange rates for various credit cards that the banks pay to the card issuing banks. Merchant fees are subject to a markup by the processors.
Links to the Visa and MasterCard statements on the settlement can be found below.
Note this doesn’t mean merchants can start charging surcharge fees on credit cards. The settlement still has to be ratified by the provinces and rules put into place.