Using individual-level data from the 2008 National Study of the Changing Workforce, we quantify how workers' job satisfaction levels correlate with five schedule-based workplace flexibilities. The data permit us to control for numerous variables that might otherwise explain variation in the probability of job satisfaction, including, but not limited to, income, benefits, stress, depression, job control and individual preferences over flexibilities. Conditional on this control set, we find that workplace flexibilities correlate with an 8.1 per cent increase in job satisfaction. The relationship between job satisfaction and workplace flexibilities prevails through several sensitivity analyses, bias assessments and a propensity score matching analysis. We also explore how job satisfaction, union membership and workplace flexibilities intermix; we find that workplace flexibilities may function as a partial substitute for union membership.