According to reactance theory, humans are universally motivated to maintain freedom, and threats to freedom can elicit resistance to requests or persuasion attempts. Although this effect is well documented, it is unclear how threats to other motivations may operate. We therefore examined this question, using a volunteer context. 668 individuals read online scenarios describing a hypothetical volunteer organization. Each scenario threatened one of six distinct motives commonly endorsed by volunteers (protection, understanding, social, career, enhancement, values), and a control condition threatened none. Participants then responded to a request by the organization. Those exposed to threats were significantly less likely to accept the request, and rejection rates were especially pronounced when personally endorsed motives were targeted. These findings suggest that psychological reactance may occur following threats to a wider variety of motivations than previously proposed, broadening the applications of reactance theory and also demonstrating the importance of individual differences in motivation.