Housing is well understood to be an important social determinant of physical and mental health and well-being. In the context of ongoing national and state efforts to reform health care, it is important for policymakers to understand the various pathways through which housing affects health. Affordable housing alleviates crowding and makes more household resources available to pay for health care and healthy food, which leads to better health outcomes. High-quality housing limits exposure to environmental toxins that impact health. Stable and affordable housing also supports mental health by limiting stressors related to financial burden or frequent moves, or by offering an escape from an abusive home environment. Affordable homeownership can have mental health benefits by offering homeowners control over their environment. Affordable housing can also serve as a platform for providing supportive services to improve the health of vulnerable populations, including the elderly, people with disabilities, and homeless individuals and families. Safe, decent, and affordable housing in neighborhoods of opportunity can also offer health benefits to low-income households.