A system and method for enabling a user to purchase an instant mobile telephony services plan makes use of an application on a mobile telephony device. The user can purchase an instant mobile plan via a third party merchant. Once purchased, the user can also make use of the application on the user's mobile telephony device to obtain the purchased telephony services. The communications services provider that provides services to the user under an instant mobile plan may be different from the communications services provider that is tied to the user's mobile telephony device.