This meta-analysis investigates gender differences in economic negotiation outcomes. As suggested by role congruity theory, we assume that the behaviors that increase economic negotiation outcomes are more congruent with the male as compared with the female gender role, thereby presenting challenges for women's negotiation performance and reducing their outcomes. Importantly, this main effect is predicted to be moderated by person-based, situation-based, and task-based influences that make effective negotiation behavior more congruent with the female gender role, which should in turn reduce or even reverse gender differences in negotiation outcomes. Using a multilevel modeling approach, this meta-analysis includes 123 effect sizes (overall N = 10,888, including undergraduate and graduate students as well as businesspeople). Studies were included when they enabled the calculation of an effect size reflecting gender differences in achieved economic negotiation outcomes. As predicted, men achieved better economic outcomes than women on average, but gender differences strongly depended on the context: Moderator analysis revealed that gender differences favoring men were reduced when negotiators had negotiation experience, when they received information about the bargaining range, and when they negotiated on behalf of another individual. Moreover, gender differences were reversed under conditions of the lowest predicted role incongruity for women. In conclusion, gender differences in negotiations are contextually bound and can be subject to change. Future research is needed that investigates the underlying mechanisms of new moderators revealed in the current research (e.g., experience). Implications for theoretical explanations of gender differences in negotiation outcomes, for gender inequalities in the workplace, and for future research are discussed.