A computer system and method for operating a computer system for a secure mobile bill presentment and payment system that enables bill payments to be made by a user of a mobile device, such as a cellular phone, smart phone, PDA, notebook, tablet or other network connected mobile device, a biller to send product or service messages or related information to enrolled customers in the mobile bill payment computer system, and for a biller to create a marketing broadcast for a product or service that an enrolled customer can purchase via the computer system.