Adherence to HIV antiretroviral therapy (ART) is a crucial factor in health outcomes for people living with HIV (PLWH). Interventions to support ART adherence are increasingly focused on the household as a source of social support. This review aims to examine the social and structural determinants of support for ART adherence within households and families in low- and middle-income countries (LMICs). The review methodology followed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Seven databases were searched for peer-reviewed literature. The terms searched thematically covered (1) ART adherence, (2) household and family and (3) support and care. Thirty-three studies conducted in 15 LMICs were selected and a mixed methods synthesis was undertaken. Social and structural determinants affected the type, quality and amount of support for PLWH of all ages, which affected PLWH’s ART adherence. Gender norms affected the type of support that household members give to PLWH. Education moderated household support for ART adherence through literacy and language skills. Cultural context, religious beliefs, and social norms reinforced or undermined household support for ART adherence. Stigma affected disclosure, generated secrecy around giving medication and impeded access to support from the community. Supporting PLWH exacerbated economic hardship for household members. Health system dysfunction negatively impacted trust and communication between household members and health professionals. Intersecting social and structural determinants particularly affected the care given by household members who were older, female, with little education and low socioeconomic status. Household members were able to overcome some of these barriers when they received support themselves. Household interventions to support PLWH’s ART adherence should take structural factors into account to have maximum impact.