Abstract: A system and associated methods are disclosed for enabling users to use third party account login information to make payments to merchants. A payment service receives a user's identifier in response to a user authentication request sent over a network to an authentication service of an information or credit service. The user authentication request includes login credentials of the user for the information service or credit and is associated with a payment page of a merchant that has an account with the payment service. The payment service receives the user identifier when the information or credit service validates the login credentials. Based at least in part on the user identifier, the payment service receives payment information from the information or credit service. The payment service provides the user with an option to use the retrieved payment information to make a payment to the merchant.