A repeat payment computer system includes a merchant server and mobile billing operator server that are programmed for user acquisition through carrier billing and subsequent conversion to credit card billing. An advantage of the process is that the user does not have to enter credit card information for the default billing cycles to occur. The user only enters a phone number and password. Fewer barriers are provided for the user to become a regular repeat customer of the merchant server. The fees associated with mobile billing according to the default billing cycles have to be paid by the merchant server and may be too high in the long run. The merchant server can avoid the high fees associated with carrier billing by switching the user to billing according to the credit card information provided. The user is typically switched after the user has already become a regular customer.