<p>Enacting fairness remains a persistent challenge for managers, prompting the need to understand how they can better treat their subordinates. Addressing this challenge, we investigate whether, how, and when mindfulness facilitates managers’ adherence to fairness. Through the lens of Social Cognitive Theory, we frame mindfulness as a metacognitive skill and propose that it enhances managers’ enactment of justice by fostering their moral potency, while this effect is diminished under high-workload conditions. We tested these ideas across two studies. Study 1 (<i>N</i> = 201), an experiment conducted with graduate business students from cooperative education programs, showed that a brief 15-min mindfulness intervention significantly increased moral potency relative to an active control condition, providing causal evidence for the proposed mechanism. Study 2 (<i>N</i> = 419), a three-wave study of managers in the United States and the United Kingdom, offered full support for the overall moderated mediation model. Together, these studies advance the mindfulness and justice literature by clarifying moral implications and contextual boundaries of mindfulness.</p>