State-Level Estimates of Gains in Insurance Coverage Among Young Adults

Background on ASPE Issue Brief

New results from the National Health Interview Survey (NHIS) indicate that 3.1 million additional young adults have insurance coverage as of December 2011, due to the provision in the Affordable Care Act that allows 19 through 25 year olds to remain on their parents’ insurance plans.

Methods

The NHIS survey is not large enough to allow estimates of how many young adults gained coverage within each State.  So to estimate these numbers, analysts from the Department of Health and Human Services used the most recent state-level, Census Bureau data from before the Affordable Care Act provision went into effect.  They calculated the number of 19 through 25 year olds who did not have health insurance in each state as of 2009 using the Census Bureau’s largest source of state-level data, the American Community Survey.  They then divided up the estimated 3.1 million young adults who have gained insurance proportionately across all 50 states and the District of Columbia, based on their baseline number of uninsured adults in this age group. 

This approach is only a rough approximation.  It assumes that the effect of the Affordable Care Act’s provision for young adults was similar across all states.  This may not be true for several reasons, including differences in population demographics, parental availability of health insurance, and pre-existing laws in some states that already enabled a portion of young adults to enroll in their parents’ plans.  

However, it is notable that the pre-existing State laws in this realm did not apply to private self-insured plans, which are covered under the Affordable Care Act’s dependent coverage provision.  The majority of U.S. workers with insurance (60%) are in self-insured plans not subject to these state laws.^[1]   

Additionally, many states had age limits, requirements for student status, or exclusions for married young adults that further limited the impact of these laws. Due to these issues, the vast majority of young adults in the U.S. were not eligible for coverage under pre-existing state laws, which minimized their impact.  This conclusion is supported by research published in peer review journals.  One study showed that pre-existing state laws produced only a small gain in coverage of roughly three percent,^[2] while two others showed no overall gain in coverage.^[3],^[4] There is no evidence that any state experienced anything close to the 10 percentage-point gain in coverage due to the Affordable Care Act’s dependent coverage provision.   

Results

Table 1: Estimated Number of Young Adults (19-25) by State Gaining Health Insurance Due to the Affordable Care Act, through December 2011