While Malawi’s Farm Input Subsidy Program (FISP) has been the focus of numerous studies on the impacts of subsidies on farm-household income, yields, fertilizer use and adoption, there still has not been much empirical work quantifying the program’s effects on maize supply and demand. In this study, we use the econometric framework proposed by Roberts and Schlenker (2013) to identify the effect of FISP on maize production as well as supply and demand price elasticities in Malawi. We use national aggregate data and find that the program has increased aggregate maize supply. Our results show that FISP has had an aggregate effect across years of about 3,746,870 metric tons from 2006-2013. We also find that the program has increased farmers’ responsiveness to changes in fertilizer prices. However, our estimates suggest that higher prices lead to higher quantities of fertilizer demanded, a relationship that is not consistent with economic theory.