An email payment gateway may be configured to send emails to customers, including a plurality of mailto hyperlinks. Each mailto hyperlink may be in the form of a graphical user interface button associated with one or more products. Each button generates a return email message when the button is selected. The generated email message may include one or more parameters related to the one or more products associated with the button, such as an identifier of the product, vendor or particular campaign with which the product is associated. The generated email message may then be transmitted to the email payment gateway. The email payment gateway may receive the message and, based on the parameters in the received message, process payment to complete the customer's purchase of the selected product.