Using data from the Current Population Survey from 2000 to 2014, this report presents results from an evaluation of the effects of the ACA on the labor supply of nonelderly adults. Results indicate that neither the ACA as a whole, or the Medicaid expansions in particular, had any adverse effect on labor supply. For adults with a high school education or less, employment is 1.8 percentage points higher than what would be expected in 2014 based on previous trends, and part-time employment is 0.5 percentage points higher than expected, but there is no such difference in employees’ usual hours worked.