Access to safe drinking water supply in Ethiopia is among the lowest in sub-Saharan Africa. While both governmental and non-governmental organizations have implemented water supply projects in recent years, many fail shortly after construction due to improper management. In this paper, we examine socio-economic, institutional and exogenous factors affecting household participation in the management of water supply systems for drinking purposes. A survey was carried out involving 16 water supply systems and 160 households within the Achefer area, in the Amhara region, Ethiopia. The results show that household contributions to water supply system management are positively and significantly affected by user participation during the project design and implementation, by advocacy provided by the project and by greater household income. Thus, for drinking water systems in rural areas to be sustainable, these factors should be included when planning water supply projects.