Men have been observed to have a greater willingness to compete compared to women, and it is possible that this contributes to gender differences in wages and career advancement. Policy interventions such as quotas are sometimes used to remedy this but these may cause unintended side-effects. Here, we present experimental evidence that a simple and practically costless tool—priming subjects with power—can close the gender gap in competitiveness. While in a neutral as well as in a low-power priming situation men are much more likely than women to choose competition, this gap vanishes when subjects are primed with a high-power situation. We show that priming with high power makes competition entry decisions more realistic and also that it reduces the level of risk tolerance among male participants, which can help explain why it leads to a closing down of the gender gap in competitiveness.