This brief examines the impacts of the Affordable Care Act on health insurance coverage and the uninsured. The brief concludes that states will benefit from the establishment of marketplaces and income-related subsidies. Employer coverage is not expected to change significantly. States that are expanding Medicaid will have larger gains in insurance coverage than those states that do not and will see very large reductions in the number of uninsured. Those states that have not expanded Medicaid will see less impact on the uninsured. These states have more uninsured to begin with, thus current disparities in coverage will increase, at least in the early years.