Uninsured near-elderly people may be particularly at risk for adverse health outcomes. We compared mortality of a nationally representative cohort of insured and uninsured near-elderly people with stratification by race; income; and the presence of diabetes, hypertension, or heart disease, using propensity-score methods to adjust for numerous characteristics. Lacking health insurance was associated with substantially higher adjusted mortality among adults who were white; had low incomes; or had diabetes, hypertension, or heart disease. Expanding coverage to the near-elderly uninsured may greatly improve health outcomes for these groups.