We aim at disentangling the impact of effort on envy. To do so we observe the impact of effort on individual well-being and behaviour. In our experiment subjects are paired and receive endowments whether according to their performance in a real-effort task or randomly. We focus on subjects placed in situations of inferiority and ask them to report their satisfaction level before and after being exposed to unflattering social comparison. Finally, subjects can choose to reduce their opponent’s endowment by incurring a personal cost. We convey that the introduction of effort does not affect individual well-being and partially subjects’ decisions to reduce others’ income. Subjects do not reduce more often their opponent’s endowment but they cut a greater portion of their opponent’s endowment when endowments are attributed according to individual performance. Besides we observe that poor performing subjects are more prone to reduce others’ income than high performing on es. We discuss the motivations behind subjects’ decisions.