This paper examines the impact of limited access to formal savings services on business growth in poor countries, using a randomized field experiment in rural Kenya. The study focuses on two types of self-employed individuals: market vendors (mostly women) and bicycle-taxi drivers (all men). Despite high withdrawal fees, a significant portion of market women used the accounts, increased their savings, and invested more in their businesses, leading to higher private expenditures. In contrast, bicycle-taxi drivers showed no significant impact. The findings suggest that market women face significant barriers to savings and investment, and further research is needed to understand these barriers and test the generalizability of the results to other types of businesses or individuals. The study also highlights the potential role of informal savings mechanisms and the need for more comprehensive financial services to alleviate poverty.This paper examines the impact of limited access to formal savings services on business growth in poor countries, using a randomized field experiment in rural Kenya. The study focuses on two types of self-employed individuals: market vendors (mostly women) and bicycle-taxi drivers (all men). Despite high withdrawal fees, a significant portion of market women used the accounts, increased their savings, and invested more in their businesses, leading to higher private expenditures. In contrast, bicycle-taxi drivers showed no significant impact. The findings suggest that market women face significant barriers to savings and investment, and further research is needed to understand these barriers and test the generalizability of the results to other types of businesses or individuals. The study also highlights the potential role of informal savings mechanisms and the need for more comprehensive financial services to alleviate poverty.