The GSM Billing System is an application that will help in providing support to the post paid meters which can be managed remotely through SMS on GSM. It provides the facility to the customers of paying the bill through the online mode with great ease. The user interface must be simple and easy to understand even by the common man. The database must be strong enough to hold all the information. The existing system involves manual work to generate the bill. It can also solve the standard problems existing in operation and maintenance of the utilities. This will be one of the interesting applications that one can work and implement in real time world.