The concept of Organizational Citizenship Behaviour (OCB) among teachers has gained significant attention in recent educational research, especially in relation to the prevailing organizational climate of schools. Organizational climate refers to the shared perceptions and emotional tone of the work environment that influence the attitudes and behaviors of employees. In the context of public and private schools, the organizational climate plays a crucial role in shaping how teachers perceive their roles, responsibilities, and their willingness to go beyond formal job expectations. OCB encompasses voluntary behaviors such as altruism, conscientiousness, sportsmanship, civic virtue, and courtesy, which are not formally rewarded but are essential for the smooth functioning and overall effectiveness of schools. The foundation of this study lies in social exchange theory and organizational behavior frameworks, which suggest that when teachers experience a supportive, respectful, and participatory climate, they are more likely to reciprocate with positive organizational behaviors. Public schools, often characterized by bureaucratic structures, may offer job security but sometimes lack the flexibility and motivational climate seen in private schools. In contrast, private schools, while more performance-driven, often provide recognition and innovation-oriented environments that can enhance OCB, provided they avoid excessive work pressure. The study assumes that a favorable organizational climate—marked by trust, mutual respect, collaborative leadership, and effective communication—acts as a catalyst for encouraging teachers to contribute voluntarily to institutional success. The discourse also highlights that leadership style, institutional policies, and interpersonal relationships serve as mediating variables that influence the climate-OCB relationship. This framework underlines the importance of school management in both sectors to nurture climates that inspire and sustain teachers’ OCB, thereby improving educational quality, team cohesion, and student achievement. Thus, understanding and enhancing organizational climate becomes a strategic priority for educational development in both public and private school systems.