March 7 2014
Although one of the primary objectives of the Affordable Care Act (ACA) is to achieve near-universal health insurance coverage, the Congressional Budget Office projects that 30 million residents, more than 10 percent of the nonelderly population, will remain uninsured after the major provisions of the ACA take full effect. The ACA extends health insurance through two direct avenues: expanding existing state Medicaid programs and providing tax credits to purchase private coverage on the health insurance exchanges, or “marketplaces.” Some uninsured individuals, despite having access to these public assistance programs, will choose not to enroll. However, a substantial percentage of the remaining uninsured will not have access to public assistance, and hence are “left behind” by the ACA.
We used the Survey of Income and Program Participation (SIPP), a nationally representative household survey conducted by the U.S. Census Bureau, and data from RAND's COMPARE microsimulation model to determine what fraction of people who were uninsured before the ACA took effect would be ineligible for Medicaid or marketplace tax credits. Figure 1 shows that, among the 52 million people who would be uninsured without the ACA, 64 percent, or about 33 million people, become newly eligible for public assistance programs due to the law. However, roughly 19 million people, or 36 percent of the previously uninsured population, are ineligible for either of the new public assistance programs offered by the ACA. Who are these individuals?