A computer-implemented method, to facilitate processing a payment for an online transaction, includes, responsive to receiving secure transaction data from a merchant server, using a payment processor to generate a transaction data identifier to identify the transaction data. The payment processor communicates the transaction data identifier to the merchant server. In response to receiving a request to process a payment, including the transaction data identifier, the payment processor requests user credentials from a user. Upon receiving user credentials from the user, the payment processor verifies the user credentials. The payment processor processes the payment and generates a payment identifier to identify payment data associated with the payment. The payment processor communicates the payment identifier to the merchant server. Upon receiving a request for payment data, including the payment identifier, over a secure communication channel from the merchant server, the payment processor communicates the payment data to the merchant server.