This paper examines household ownership and use of insecticide-treated mosquito nets (ITNs), based on data from six Demographic and Health Surveys (DHS) and one Malaria Indicator Survey (MIS) conducted in sub-Saharan Africa from 2004-06. The paper has a particular focus on children under age five and pregnant women in households that own at least one ITN. Overall, there is considerable variation in the ownership and use of ITNs among these groups, while there are several striking common findings across groups. There is no country in the study where more than half of households own an ITN, but even in households that own an ITN, members of the household do not necessarily use them. In five of the seven countries, in households that own an ITN the majority of children under age five (50-69 percent) and pregnant women (56-81 percent) use an ITN. In all countries, two variables—the number of ITNs in a household and the size of the household population—predict the use of ITNs. ITN use increases with the number of ITNs in the household, but decreases as the size of the household increases, as measured by the percentage of the household population using an ITN. The effects of several other variables are inconsistent; place of residence predicts ITN use consistently only in Tanzania and Uganda where rural residents are less likely than urban residents to use an ITN. In Senegal, household wealth is negatively associated with ITN use among the total household population and among children under age five; wealth is positively associated with use among the household population in Mali and Tanzania and among pregnant women in Mali. In Tanzania, children in the poorest households are least likely to use an ITN. Finally, children who are breastfeeding are not more likely to use an ITN than non-breastfeeding children, with the exception of Mali. Mother’s level of education does not significantly predict ITN use for the child, although the mother’s use of an ITN herself is highly correlated with use by the child. Overall, the study results underscore the need for malaria control programs to take into consideration the number of members in a household when distributing nets and to pay close attention to country-specific conditions when designing and implementing ITN distribution and promotion programs.