Tanzania is among the African developing countries that has embraced egovernment in recent years. The continual rises of wireless mobile technology bring an attention to enhance e-government systems by extending some of the services to be accessed and delivered via a mobile phone. Due to lack of standard extension procedures each government institutions extends according to developer’s technical knowledge. The main objective of this paper is to develop extension procedures for enhancing web based e-government systems with a mobile service. In this study both exploratory and prototyping methods were used. Exploratory method was used during data collection. Prototyping was used during design and development of mgovernment service prototype. Web based e-Government systems in fourteen (14) Government departments, Ministries and Agencies were analyzed to identify a system for enhancement. Wananchi portal, under the Ministry of information, culture art and sports was selected. The selection criteria were the system that has direct interaction with citizens. During design and development of m-service prototype, several extension procedures and their interactions were observed and recorded; six (6) procedures were found relevant. Therefore, this paper proposes a six steps extension procedures from web based e-government to m-government. Clear understanding of the extension process will reduce development time and cost. Extending web based system with mobile services means extra services and hence more revenue to network and service providers. To the government, it means an added/alternative channel to service her citizens, and to the citizens, means readily accessible and responsive Government