# Block Mastercard debit and Visa debit cards using Radar

You can block transactions from Mastercard debit and/or Visa debit cards by creating a custom block rule in [Stripe Radar](https://stripe.com/docs/radar).
From the [Rules](https://dashboard.stripe.com/radar/rules) section of your [Radar dashboard](https://dashboard.stripe.com/radar):
1. Scroll down to the **When should a payment be blocked?** section.
1. Click **+ Add rule**.
1. Add the following block rule depending on the card type you want to block:
   * **Mastercard debit cards:**
     `Block if :card_funding: = 'debit' and:card_brand: = 'mc' and :card_country: = 'CA'`
   * **Visa debit cards:**
     `Block if :card_funding: = 'debit' and :card_brand: = 'visa' and :card_country: = 'CA'`
1. Click **Test rule** to ensure the block rule is functional.
1. Click **Add and enable** once the block rule test completes successfully.
The above rules block cards based on their `card_brand` as well as the `card_country` attributes, which is represented as the [two-letter ISO country code](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) for this country. In this case, CA is for Canada.