With the Rewards API you can Allow your customers to securely integrate their Capital One miles, point or cash rewards data into your application. This API exposes the following capabilities:

Retrieve customer accounts — returns a list of the active rewards accounts associated with a customer; returns only those accounts for which the customer has granted access permission and those which have passed the internal Capital One entitlements check.

Retrieve rewards account details — retrieves detailed information about the referenced rewards account, including the currency in which rewards are accumulated (miles, points, or cash back), the rewards account balance, and whether or not the balance is eligible for redemption.