Implementing automated Medicaid eligibility renewals was not associated with higher levels of program participation.

Increasing participation in Medicaid among eligible individuals is critical for improving access to care among low-income populations. The administrative burdens of enrolling and renewing eligibility are a major barrier to participation. To reduce these burdens, the Affordable Care Act required states to adopt automated renewal processes that use available databases to verify ongoing eligibility. By 2019, nearly all states adopted automated renewals, but little is known about how this policy affected Medicaid participation rates. Using the 2015-2019 American Community Survey, we found that participation rates among nondisabled, nonelderly adults and children varied widely by state, with an average of 70.8% and 90.7%, respectively. Among Medicaid-eligible adults, participation was lower among younger adults, males, unmarried individuals, childless households, and those living in non-expansion states compared with their counterparts. State adoption of automated renewals varied over time, but participation rates were not associated with adoption. This finding could reflect limitations to current automated renewal processes or barriers to participation outside of the eligibility renewal process, which will be important to address as additional states expand Medicaid and pandemic-era protections on enrollment expire.