Understanding Cross-State Variations in Medicaid Enrollment During and After the COVID-19 Pandemic

Due to the implementation and unwinding of a ``continuous coverage requirement'', the COVID-19 pandemic gave rise to the most dramatic changes in Medicaid enrollments in the program's history. Nationwide, enrollments rose by 23 million individuals from February 2020 through March 2023, then declined by roughly 15 million by late 2024. Notably, changes in per capita enrollments varied dramatically across the country, with several states experiencing net declines and several states seeing their enrollments rise, on net, by more than 5 percent of their populations. Through a mix of descriptive and causal analyses, we explore several hypotheses regarding the possible causes of these variations. We find that a wide range of provisions designed to ease the frictions of the continuous coverage provision's winding down have surprisingly little predictive power. Similarly, we find that variations in federal aid to state and local governments has no predictive power, suggesting that liquidity constraints had little influence on states' management of Medicaid enrollments during this period. Variations in political preferences, as proxied by Trump's 2016 vote share, have modest predictive power within the unwinding episode. Finally, states that enacted Medicaid expansions during the pandemic experienced relatively large net gains in enrollments. The baseline generosity of states' eligibility thresholds also predicts relatively large run-ups and net increases in enrollments.