The objective of this study is to determine the effect of permethrin insecticide-treated bed net (PITN) use on the incidence of febrile episodes and on household malaria expenses in Benin. Over the course of one year, 208 randomly selected PITN user and non-user households were visited weekly to determine expenditures on febrile morbidity and its treatment, and to monitor spending on malaria prevention. Multivariate analyses were performed to distinguish the effects of PITN use from other important determinants of morbidity, such as malaria-related beliefs and practices, income, and other socio-economic variables. Results from the logistic regression analysis show that the use of PITNs decreases the risk of febrile episodes by 34% in children living in the rural zone. Multiple regression analysis reveals that PITN use does not reduce prevention and treatment expenses. These expenses are significantly associated with women's income. This report also discusses other factors associated with febrile morbidity and malaria-related expenditures.