Lack of access to safe drinking water is a crisis of great proportion. An estimated 1.8 billion people rely on unsafe drinking water. This study focuses on the case of Tanzania, in which an estimated 29 million people, or 44% of the population, lack access to safe drinking water. Furthermore, the Tanzanian Ministry of Water estimates that approximately 38% of all water access points in the country are nonfunctional. As the Government of Tanzania and other actors work to improve water access, they employ innovations to facilitate water service delivery that is both high quality and sustainable over time. These innovations must be field-tested prior to large-scale implementation to ensure they are appropriate and effective in varying contexts. User perceptions of innovations are valuable for gauging the potential benefits and barriers to incorporating new innovations in the water sector. This study investigates the use of solar power and mobile prepayment to improve water services in Tanzania. There are currently no data on user perceptions of these innovations in Tanzania. Thus, this study fills this data gap through the analysis of focus group discussions (n=6) and key informant interviews (n=14) collected during summer 2016 in three urban and three rural communities in Tanzania. Urban sites are located in the city of Dar es Salaam, and rural sites are scattered throughout Tanzania. Using qualitative methods, this study identifies themes related to user perceptions of water services, solar power, and mobile prepayment. While perceptions varied between urban and rural study settings and within study sites, most people perceived major challenges with the current water system. These perceived challenges included the poor reputation of the water service provider, health problems related to water, and the general lack of consistent high-quality water provision. Research participants perceive that mobile prepayment is a modern solution to water service challenges, but perceive that cost, particularly for the poor, may be a barrier. Generally, people in the rural setting perceive that solar power will reduce costs and increase water service reliability, while those in Dar es Salaam were less familiar with the technology. While perceptions indicate that solar and mobile phone innovations have great potential in both urban and rural settings, they also indicate that there exist significant challenges to implementing the innovations. User perceptions ultimately manifest in real behaviors related to water services, and thus must be incorporated before these innovations are scaled-up across Tanzania.