Malaria is a major cause of morbidity and mortality in Liberia. At the same time, insecticide-treated net (ITN) ownership and use remain low. Access is a key determinant of ITN use but it is not the only one; prior studies have identified factors that affect the use of ITNs in households with at least one ITN. These factors operate at the individual, household, and community levels. However, studies have generally not assessed the psychosocial or ideational determinants of ITN use. Using 2014 household survey data, this manuscript examines the socio-demographic, ideational, household, and community factors associated with household member use of ITNs in Liberia. Multilevel modeling was used to assess fixed effects at the individual, household, and community levels, and random effects at the household and cluster levels. The data showed significant residual clustering at the household level, indicating that there were unmeasured factors operating at this level that are associated with ITN use. The association of age with ITN use was moderated by sex such that men, older children, and teenagers were less likely to sleep under an ITN compared to women and children under five years old. Female caregivers’ perceived severity of malaria, perceived self-efficacy to detect a complicated case of malaria, and exposure to the “Take Cover” communication campaign were positively associated with ITN use by members of her household. The association with household size was negative, while the relationship with the number of ITNs was positive. Programs should seek to achieve universal coverage (that is, one ITN for every two household members) and promote the notion that everyone needs to sleep under an ITN every night. Programs should also seek to strengthen perceived severity of malaria and educate intended audience groups on the signs of malaria complications. Given the significance of residual clustering at the household level, interventions that engage men as heads of household and key decision-makers are relevant.