The Ga West Municipal Assembly was carved out of the erstwhile Ga municipal which was created in 1988 in pursuance of the government decentralization and local government reform policy. In 2004, the Ga Municipality was divided into two with Amasaman the former municipal capital remaining the capital for the newly created Ga West Municipal.

The Ga West Municipal is the second largest of the six Municipalities & Districts in Greater Accra Region. It lies within latitude 5048’ North 5029’ North and longitude 008’ west and 0 030’ West.  The Municipal shares common boundaries with Ga East Municipal and Accra Metropolitan Assembly to the East, Akwapem South, Suhum Kraboa Coalter and West Akim Municipal to the North, Awutu Efutu Senya to the West and the Gulf of Guinea to the South.  It occupies a land area of approximately 710.2 sq km with about 1028 communities.