Research finds the behavioral implications of public service motivation (PSM) in prosocial behaviors such as volunteering, and explains the higher rate of volunteering among public and nonprofit workers with PSM. Although existing research focuses on the link between employee’s PSM and general volunteering, little is known about how workers’ volunteering activities differ across the public, private, and nonprofit sectors. This study examines differences between public and nonprofit employees’ volunteering focusing on the types of organizations where they volunteer. The results indicate distinctive patterns of volunteering between public and nonprofit sector workers: Nonprofit workers are more likely to volunteer in religious and social/community organizations, whereas public workers are more likely to volunteer in educational organizations. The findings of this study call for a more systematic and multifaceted approach to understanding the link between PSM and volunteering.