If you find unauthorized transactions on your credit card account, follow the steps below to find out whether you can be reimbursed:
Step 1: Contact your credit card issuer immediately to report the unauthorized transactions.
Step 2: Check your credit card agreement. By law, your agreement must contain a section that explains your maximum liability (usually $50) in the case of lost or stolen credit cards, or the unauthorized use of your credit card account number.
Step 3: Find out if your credit card issuer offers "Zero-Liability" on unauthorized transactions. For example, Visa and MasterCard cardholders are protected beyond the maximum liability found in their credit card agreements. This is done through a public commitment Visa and MasterCard call the "Zero-Liability Policy". If your Visa or MasterCard is lost or stolen, or if someone uses your Visa or MasterCard account number to make transactions you did not authorize, you can usually be reimbursed.
This policy applies to transactions made on the Internet, by phone or at retailers, but may exclude personal identification number (PIN)-based transactions - for example, a cash advance made on your card at an automated banking machine (ABM) - and transactions made on corporate credit cards. Find out from your credit card issuer whether they have such a policy and how it can protect you. Note that these policies are not listed in credit card agreements, since they are public commitments and not legal requirements.
Source: Financial Consumer Agency of Canada http://www.fcac-acfc.gc.ca/