Abstract: A system, method, and computer-readable medium for user authentication and mobile payment authorization are provided. A user operating a mobile terminal may submit a product for purchase at a point-of-sale and submit the user's phone number and personal identification number thereto. An authentication and authorization process is then performed to authenticate the user and authorize the purchase. Upon authentication and authorization, a one-time-password is transmitted to the point-of-sale and the user's mobile terminal. The user provides the one-time-password as input to the point-of-sale which compares the one-time-password provided by Mobile Payment System with the one-time-password provided by the user to determine whether to approve or deny the purchase. Multiple users each having different authorization levels and purchase limits may be associated with a common account, and each user may have a distinct identifier used to authenticate the particular user of the account.