Trends in Medicaid and CHIP Eligibility Over Time

Over time eligibility for Medicaid and the Children’s Health Insurance Program (CHIP) has expanded to provide a base of coverage for the low-income population, which was most recently strengthened through the Affordable Care Act (ACA) Medicaid expansion as of 2014. While eligibility has increased over time, eligibility levels vary significantly across states and eligibility groups. This analysis examines trends in Medicaid and CHIP eligibility limits over time for children, pregnant women, parents, and other adults. It also explores how trends in eligibility for these groups vary by several variables, including geographic region, Medicaid expansion status, and state health ranking. (Eligibility levels for all 50 states and DC over time are available at Key findings include the following:

  • Eligibility for children and pregnant women has been consistently higher than for parents and other adults over time. The ACA Medicaid expansion narrowed the gap between medians for these groups, but median eligibility limits for parents and other adults still are lower than those for children and pregnant women.
  • Across eligibility groups, the Northeast generally has had the highest median eligibility limits. The South has the lowest median eligibility limits for all groups, except pregnant women, for whom the West has the lowest median eligibility limits. Over time, the gap between the region with the highest median eligibility limit and the region with the lowest median eligibility increased for children. This gap also widened for other adults when the Medicaid expansion took effect as of January 2014. In contrast, the gap between the highest and lowest regions has narrowed for parents and pregnant women over time.
  • States that implemented the Medicaid expansion have higher median eligibility limits compared to non-expansion states for all eligibility groups, and the gap between expansion and non-expansion states widened for all groups over time. As expected, the largest differences emerged for parents and other adults after implementation of the expansion in 2014. However, the difference between the median income limit for children in expansion states and non-expansion states also grew over time. The gap is smaller for pregnant women and has recently begun to narrow.
  • For children, parents, and other adults, states with the lowest health rankings have the lowest median eligibility limits over time, while states with the highest health rankings have the highest median eligibility limits. Gaps between median income eligibility limits for high and low health ranking states are largest for other adults and children. This gap also exists for parents, but it narrowed after implementation of the Medicaid expansion. For pregnant women, middle health ranking states have the highest median eligibility limits. While the high and low health ranking states have lower median eligibility limits compared to the middle health ranking states, the differences in median eligibility limits by health ranking are smaller for pregnant women compared to the other eligibility groups. These findings provide insight into how coverage levels vary by health needs; however, it is important to recognize that this is not a causal relationship given that health is impacted by a broad range of factors beyond health coverage and health care.

This analysis is based on 16 years of eligibility data collected by the Kaiser Commission on Medicaid and the Uninsured with the Center on Budget and Policy Priorities, 2000-2009; and with the Georgetown University Center for Children and Families, 2011-2015. The income eligibility limits are reported as a percentage of the federal poverty level (FPL), which is calculated each year by the Department of Health and Human Services. As of 2015, the FPL is $11,770 for an individual and $20,090 for a family of three.

The data show changes in eligibility levels by group over time as well as the impact of the ACA on eligibility. Prior to the ACA, states generally could not receive federal Medicaid matching funds to cover non-disabled adults without dependent children. As enacted, the ACA expanded Medicaid eligibility to adults with incomes at or below 138% FPL beginning in 2014, although this provision was effectively made a state option by the Supreme Court’s 2012 ruling on the ACA. Other eligibility changes established by the ACA went into effect across all states as of January 1, 2014, including establishing a new minimum eligibility level of 138% FPL for children of all ages in Medicaid and changing the method for determining financial eligibility for Medicaid for children, pregnant women, parents, and adults and CHIP to a standard based on modified adjusted gross income (MAGI). As such, the changes in eligibility levels between 2013 and 2014 reflect both changes in eligibility policy, including adoption of the Medicaid expansion, as well as the conversion to the MAGI-based standards. While many of the converted 2014 standards appear higher than 2013 levels, the converted thresholds are intended to approximate states’ existing eligibility levels using different methodology for determining income.

Section 1: Eligibility Trends by Group

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