Click to Pay Customer Authentication {#uc-authentication}
=========================================================

When you enable customer authentication through Click to Pay, you give `Visa Acceptance Solutions` permission to send Visa the required authentication information for each transaction. When the customer completes a transaction using a Visa card that is already stored in Click to Pay, authentication is managed within Click to Pay.  
Click to Pay authentication is only available for Visa branded cards that are tokenized with Click to Pay. If Click to Pay does not authenticate the transaction, but you are using the complete mandate with the consumerAuthentication field set to `true`, authentication is attempted as part of this request. When you do not use the complete mandate, you must check the result of the cardholderAuthenticationStatus field in the transient token and request `Payer Authentication` directly when it is required.

> IMPORTANT
> American Express and Mastercard card brands cannot be authenticated through Click to Pay customer authentication.

Authentication Flow
-------------------

![](/content/dam/documentation/cybs/en-us/topics/payments-processing/card-processing/unified-checkout/images/uc-ctp-auth-flow-740x680.svg/jcr:content/renditions/original)