A service utilizing apparatus includes an interface that transmits, to a service providing apparatus, user information together with request information that requests a user registration, and receives registration completion information indicating a completion of the user registration from the service providing apparatus. The service utilizing apparatus also includes a memory that stores the user information according to the received registration completion information. The service utilizing apparatus further includes a processor that detects a change in the service utilizing apparatus and deletes the user information stored in the memory when the processor detects the change in the service utilizing apparatus. Additionally, the interface transmits to the service providing apparatus delete request information that requests a deletion of the user information when the processor detects the change in the service utilizing apparatus.