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Debit Card security for online purchases

Simple, convenient and safe from fraud

We work hard to make your online purchases simple, convenient and safe from fraud. Your Citi Debit Card uses one of two options, Mastercard® SecureCode or Verified by Visa, as a quick and sophisticated way of identifying yourself to Citi Security when shopping online.


Mastercard® SecureCode

Mastercard SecureCode uses One Time Passwords as an enhanced way of authenticating certain transactions, helping to protect you from card fraud.

Holders of a Mastercard Citi Debit Card are automatically registered with Mastercard SecureCode.

To ensure you receive a One Time Password, it’s vital your current mobile number is registered with Citi.

How it works +

  • Mastercard monitors the security of your card 24 hours a day, 7 days a week. Each time you make an online purchase, the details are automatically checked against your usual spending patterns and the device(s) you use.
  • Regular, recognisable purchases may be authorised at once, to make using your card as convenient as possible. For some transactions Mastercard SecureCode may ask you to enter a One Time Password as an extra level of security.
  • Each One Time Password has six digits, and will be sent by text from ‘Citibank’ to the mobile phone you have registered with Citi.
  • To authenticate the purchase, enter the One Time Password in the on-screen box and press Submit. You will then be returned to the retailer’s site to complete your purchase.

Please make sure we have your current mobile number

The last four digits of the mobile number we hold for you are displayed at the top of the Mastercard SecureCode box.

If you haven’t registered your mobile number with us, or if you think the number we have for you is out of date, please contact CitiPhone on 0800 00 55 00 to update your mobile phone number, or +44 207 500 55 00 if calling from outside the UK.

How it works -


Verified by Visa

Verified by Visa uses a password and personal message as an extra layer of security to give you peace of mind when shopping online.

It’s free, quick and easy to register – all you need is your card. It’s that simple.

How it works +

  • Shop online at participating retailers and pay with your registered Visa Citi Debit Card.
  • A pop-up window will appear and you’ll automatically be prompted to enter your Verified by Visa password, like an ATM requesting your PIN. To verify that this is a genuine request from Visa, the window will display the personal message you chose at registration.
  • Enter your password to confirm your identity. This added layer of security is not shared with the retailer. Your transaction is authenticated and the purchase complete.

How it works -