Did the Affordable Care Act’s Medicaid Expansion Change Cohabitation Trends?

This study builds on past research to examine whether the Medicaid expansion provision of the Affordable Care Act (ACA) affected cohabitation rates among adults ages 18–40. This provision of the ACA was designed to expand health insurance coverage for low-income individuals. The expansion has been demonstrated to have effects beyond increased access to health services, including effects on financial health, marriage, fertility, and child support payments. Nationally representative data from the 2007 to 2019 Current Population Surveys (N = 45,129–695,629) were used to estimate difference-in-difference models of the effect of the Medicaid expansion on cohabitation. Results indicate generally positive effects of the Medicaid expansion on cohabitation, but effects are primarily limited to states expanding in 2014 and are seen 2 years after expansion. Subgroup analyses indicate some heterogeneity by parenthood and race/ethnicity; results are robust to the exclusion of early and late expansion states and to a wider age range. Findings are consistent with behavior around eligibility notches and changes in non-economic factors post-expansion that may influence cohabitation decisions. As states continue to expand Medicaid coverage, such trends may be increasingly evident.