This study explores the role of peer support as a determinant of religious character formation and student well-being in faith-based schools using a mixed-methods design. Quantitative data from 195 students were collected via Likert-scale questionnaires assessing peer support, religious character, and psychological well-being. Qualitative data were obtained through in-depth interviews and participant observation to capture how peer interactions function in daily school life. Findings show that peers serve as motivators, supervisors, advisors, and role models, reinforcing religious values and promoting positive social and emotional experiences. Peer support enhances student well-being by fostering a sense of belonging, emotional reassurance, academic motivation, and social skills such as empathy and teamwork. Religious character and peer support operate synergistically: religiosity provides meaning and life direction, while peer support energizes daily religious practices. The study highlights that integrating peer relationships with teacher-facilitated school programs creates a holistic educational environment that nurtures both spiritual development and psychological well-being.