Task performance is essential for organizations, so it continues to attract the attention of researchers, practitioners, and academics. Therefore, the purpose of this study is to explore the effect of boundary-spanning leadership and psychological empowerment on the task performance of employees in Indonesian companies through the mediation mechanism of proactive work behavior. Research data were obtained from 455 employees of companies in the financial, trade, service, and investment sectors in Indonesia. The paper employed accidental sampling using a Likert-scale questionnaire and structural equation modeling. The results show that boundary-spanning leadership, psychological empowerment, and proactive work behavior significantly affect task performance. Boundary-spanning leadership and psychological empowerment significantly affect proactive work behavior. Proactive work behavior mediated the causal relationship between boundary-spanning leadership and psychological empowerment with task performance. These findings encourage a new empirical model regarding the critical role of proactive work behavior in transmitting boundary-spanning leadership and psychological empowerment to task performance. This model can be used by scholars, researchers, and practitioners to investigate worker task performance more thoroughly and deeply from the perspectives of boundary-spanning leadership, psychological empowerment, and proactive work behavior. It can serve as a credo for corporate management professionals seeking to maximize proactive work behavior, psychological empowerment, and boundary-spanning leadership in order to enhance employee task performance. In the interim, scholars and researchers can utilize it as a guide for next task performance investigations.