According to the United Nations, the world has met the Millennium Development Goal target of halving the proportion of people without access to safe drinking water. However, global figures mask massive disparities between regions and countries, and within countries. For instance, only 64% of the people in sub-Saharan Africa have access to improved water sources. Over 40% of all people globally who lack access to drinking water live in sub-Saharan Africa. Rwanda is used as a case in point in this study. Despite the abundance of water resources in the country, access to improved water sources is limited. Using the Rwandan Demographic and Health Surveys (2000–2010), we examined regional disparities in access to improved water sources. Results from logistic regression models show that overall, access to improved water has declined between 2000 and 2010; except in the western region, where access to water marginally improved. Educated individuals, wealthier and urban dwellers were more likely to have access to improved water sources over time compared to their uneducated, poor and rural counterparts. The persistence of regional disparities in access to improved water over time suggests the need for policy to address insufficient investments in water infrastructure in Rwanda.