Objectives. To identify risk factors for Medicaid disenrollment after the implementation of Arkansas's work requirements.Methods. Using a 2018 telephone survey of 1208 low-income adults aged 30 to 49 years in Arkansas (expansion state with work requirements implemented in June 2018), Kentucky (expansion state with proposed work requirements blocked by courts), Louisiana (expansion state without work requirements), and Texas (nonexpansion state), we assessed Medicaid disenrollment rates among the age group targeted by Arkansas's policy.Results. The Medicaid disenrollment rate was highest in Texas (12.8%), followed by Arkansas (10.5%), Kentucky (5.8%), and Louisiana (2.8%). Over half of those who disenrolled in Texas and Arkansas became uninsured, compared with less than a quarter in Kentucky and Louisiana. In multivariate models, Arkansas had significantly higher disenrollment compared with the 3 comparison states; men and non-Hispanic Whites experienced higher disenrollment than women and racial minorities. In Arkansas, having a chronic condition was associated with higher disenrollment.Conclusions. As states debate work requirements and Medicaid reforms, our findings provide insights for policymakers about which populations may be most vulnerable to losing Medicaid coverage.