The Patient Protection and Affordable Care Act (ACA) will expand health insurance coverage by about 30 million people—reducing the number of uninsured by more than half. To determine who will remain uninsured, Matthew Buettgens, Ph.D., research associate, Urban Institute, and Mark Hall, J.D., Fred D. and Elizabeth L. Turnage Professor of Law, Wake Forest University, projected ACA’s effects as if it were fully implemented in 2011. They analyzed the likely composition, state-by-state, of the uninsured, finding:

• The ACA would reduce the number of nonelderly people without health insurance by 28 million—from 18.9 to 8.7 percent.
• Of the 23 million still uninsured, 40 percent would be eligible for, but not enrolled in, Medicaid or the Children’s Health Insurance Program (CHIP). A further 22 percent would be undocumented immigrants.
• The majority of those uninsured—19 of the 23 million—would be nonelderly adults:
  • Thirty-seven percent—mostly young singles without dependents—would be eligible for Medicaid, but not enrolled.
  • Twenty-five percent would be undocumented immigrants.
  • Sixteen percent would be exempt from the individual mandate because they would not have an affordable insurance option.
  • Eight percent would be eligible for affordable subsidized coverage in the health benefit exchanges.
  • The remaining 15 percent—most higher-income families with dependents—would likely be subject to the mandate, having an affordable private insurance option despite not qualifying for a subsidy.

The researchers, funded by the Robert Wood Johnson Foundation, found that composition would vary considerably among states, according to their economic and demographic characteristics, as well as other factors, such as their pre-reform Medicaid eligibility criteria. For example, the uninsured rate among the nonelderly would vary regionally from 4.6 percent in New England, to 11.4 percent in the West South Central region. Massachusetts would have the lowest rate (1.1 percent) and Texas the highest (12.8 percent).