Cardholder Resources
Everything you need to make the most of your card. Reference your card agreement, activate your card if you're using it for the first time, or find the phone numbers you need to connect with us when you need to speak with a BMO Harris Bank representative.
Access your online account
Manage your card 24/7 from the comfort of your home, office, or anywhere else you have internet access.
Activate your card or add an authorized user
Once you've received your card, call us to activate it. Or if you would like to add an authorized user to an existing card or simply have a question, call us anytime – we're here to help.
Consumer Credit Cards
- BMO Harris Bank Platinum Mastercard®
- BMO Harris Bank Platinum Rewards Mastercard®
- BMO Harris Bank Cash Back Mastercard®
- 1-855-825-9237
- BMO Harris Bank Premium Mastercard®
- BMO Harris Premier Services Premium Rewards Mastercard®
- 1-855-825-9238
Report your card lost or stolen
If your card has been lost or stolen, please call the appropriate number below immediately, to ensure your account is protected against fraudulent use.
Consumer Cards
- BMO Harris Bank Platinum Mastercard®
- BMO Harris Bank Platinum Rewards Mastercard®
- BMO Harris Bank Cash Back Mastercard®
- 1-855-825-9237
- 1-262-780-8658
(outside U.S.)
- BMO Harris Bank Premium Rewards Mastercard®
- BMO Harris Premier Services Premium Rewards Mastercard®
- 1-855-825-9238
- 1-262-780-8658
(outside U.S.)
Business Platinum Mastercard® Credit Cards
- 1-855-825-9231
- 1-262-780-8660
(outside U.S.)
Diners Club U.S. Cards
Terms & Agreements
Take a look at the benefit guides, terms, conditions and agreements for the consumer card you've chosen. If your card is not listed, or you have a BMO Harris Business Mastercard or BMO Wealth Management Mastercard, please visit bmoharris.com/legal.
Mastercard® is a registered trademark of Mastercard International Incorporated.