Due to the pressure to do more with less, public employees are having higher levels of unreasonable workload, which can negatively affect their job satisfaction. Despite this, little research examines ways to promote reasonable workload in the public sector. Based on the conservation of resources (COR) theory, this study posits that supervisor support fosters coworker support, which can offer various resources to enhance reasonable workload and in turn, job satisfaction of public sector employees. Furthermore, based on the complementary resources perspective, we propose that tangible job resources magnify the effects of supervisor support and coworker support on reasonable workload. Results of structural equation models with data from the 2019 U.S. Federal Employee Viewpoint Survey support the above hypotheses. This study is important as it demonstrates practical ways to help public employees deal with their workload and enhance job satisfaction.