The lack of health insurance is traditionally considered a problem faced by individuals and their families. However, because of the geographically bounded organization and funding of healthcare in the United States, levels of uninsurance in a community may affect everyone living there. Health economists have examined how the effects of uninsurance spillover from the uninsured to the insured, negatively affecting healthcare access and quality for the insured. We extend research on uninsurance into the domain of sociologists by theorizing how uninsurance might exacerbate social inequalities and undermine social cohesion within communities. Using data from the Los Angeles Family and Neighborhood Survey, we show that individuals living in communities with higher levels of uninsurance report lower social cohesion net of other individual and neighborhood factors and discuss implications for implementation of the Affordable Care Act.