This study analyzed the effect of improved revenue-collection efficiency strategy on the performance of WSPs in Kenya; case of Nyahururu Water and Sanitation Company (NYAHUWASCO), Nyahururu. The study used descriptive survey research design and its target population was the 86-permanent staff of NYAHUWASCO, Nyahururu as at March 2017. A stratified random sampling was adopted in which respondents from different departments were targeted and which gave the sample size of 71 members. A pilot testing of the instruments was done to a selected sample of 6 permanent staff of Nakuru Water and Sanitation Company, to test their validity and reliability. Primary data was collected using questionnaires while secondary data was collected from existing relevant documents. Data was analyzed using descriptive and inferential statistics, with the help of Scientific Package for Social Sciences (SPSS) computer program, in order to determine effect of improved revenue-collection efficiency strategy on performance of NYAHUWASCO. The study revealed that practices that improved revenue collection efficiency such as introduction of mobile payment solutions, decreasing bill collection periods, disconnection policy and increase in the number of the billed customers enhanced performance at NYAHUWASCO. The study tested a null hypothesis that stated that, improved revenue-collection efficiency strategy does not have a statistically significant effect on performance of WSPs in Kenya. The inferential statistics found that improved revenue-collection strategy effect on performance of NYAHUWASCO is statistically significant (p<0.01). Therefore the hypothesis was rejected. An increase in improved revenue collection efficiency by one unit was found to increase performance by 0.359 units of NYAHUWASCO performance when all other variables were held constant. The study recommended that the government and management should enhance revenue collection efficiency such as introduction of mobile payment solutions, decreasing bill collection periods, disconnection policy and increase in the number of the billed customers.