This study sought to examine how operational demands hinder individual well-being in firefighters, and also the extent to which fire chiefs’ transformational leadership style acts as an operational resource to attenuate this relationship. A total of 115 firefighters participated in the study and completed surveys over seven consecutive days. The results suggest that individuals’ well-being trajectories are not influenced by operational demands while individuals’ well-being is enhanced over time by team leaders’ transformational leadership. The implications of these findings are discussed and future research directions are advanced.