Single use plastics pose environmental and socioeconomic problems in our life and ecosystems. After a 14 year attempt, Kenya successfully adopted a plastic bag ban for secondary packaging in August 2017. Globally, the impact of plastic bag policies are limited or not documented. Using a questionnaire survey, this study explored consumer consciousness towards the ban, reusable bag usage behavior, and estimated plastic bag consumption before the ban. Results indicate that the ban has favorable support of about 67% from consumers. The perceptions towards cleanliness and waste management were different between urban and rural respondents. This highlighted differences in awareness creation and enforcement of the ban. Behaviorally, ownership of reusable bags tripled to 12 bags per household. Plastic reusable bags were the most owned and most discarded bags within 6 months. Moreover, a report estimates that 300 million bags (8.3–6.7 bags person−1 y−1) were consumed annually in 2005 and 2017 before the ban, the current study estimates the ban potential eliminates about 6.2 billion bags (138 bags capita−1 y−1) from the waste stream. It is thus important to incorporate usage frequency, reusable bags standards, waste and health factors in policy formulation. Proper usage of reusable bags prevents waste and lowers their environmental burden.