Billing authentication with 3D Secure
3D Secure is a payment authentication method for online credit card transactions. As required by PSD2, most online transactions within the EU will require strong customer authentication. To be compliant, Shopify will process credit card transactions in the EU using 3D Secure.
Any time that you add a credit card as a method of payment for your store's Shopify subscription plan, you're prompted for authentication. After you enter your credit card details from the Billing settings page, you are redirected to the 3D Secure page where you can set up or enter your 3D Secure PIN.
Do I need to authenticate my payments made to Shopify?
Yes. If you're using a credit card as a method of payment, then you need to go through the authentication process to complete your payment.