Effective school leadership contributes to school success by improving student learning and reducing teacher turnover. Prior research has documented that supportive leadership can help retain effective teachers and improve teacher efficacy, thereby reducing the financial and human costs associated with teacher turnover. Within the private Christian school sector, we examined the relationship between supportive leadership, teacher well-being, and teacher willingness to promote the school. Our findings show a significant, robust, meaningful relationship between teachers' perception of their leaders as supportive, higher levels of teacher well-being, and greater willingness to promote their schools to both prospective families and teachers.