OBJECTIVES: Variations among states in household exposure to firearms, loaded firearms, and handguns were examined. METHODS: Data from the Behavioral Risk Factor Surveillance System in 22 states were used to estimate the prevalence of adults and children exposed to household firearms. RESULTS: The prevalence of adults living in households with firearms ranged from 12% to 57%; the corresponding ranges were 1% to 23% for loaded firearms and 5% to 36% for handguns. The prevalence of children less than 18 years of age living in households with loaded firearms ranged from 2% to 12%. CONCLUSIONS: Important variations among states exist in the prevalence of adults and children living in households with firearms, loaded firearms, and handguns.