Adolescence is a critical phase of life characterised by changes in social, emotional, cognitive, and biological domains. During adolescence, successful emotion management and regulation bolsters positive effects and promotes achievement, whereas the absence of adaptive and interpersonal skills contributes to distress and poor well-being. Around 1.2 billion of the global population are adolescents of which 20% of them are from India (UNFPA, 2014). Adolescents are important resources for the country’s future. Therefore, the health and well-being of adolescents are of paramount importance. Strengthening the social-emotional competencies of adolescents can help them cope with challenges and enhance well-being. The delivery of an age-appropriate evidence-based SEL programme enhances social-emotional competencies and creates a respectful classroom climate to develop and grow. Therefore, the present study aimed to develop a SEL intervention and investigate its effect on the well-being of adolescents. A quasi-experimental design was employed for this study. The study sample involved 40 students studying in 9th grade aged 13–15. The participants for the study were chosen through a purposive sampling technique. The statistics employed for the data analysis were a paired t-test and a Wilcoxon rank test. The study results demonstrated a statistically significant (t =  − 10.023 p < .05) improvement in adolescents’ well-being. The study’s findings are valuable evidence for adopting SEL interventions at schools. The study, therefore, recommends the integration of SEL into educational policies and school practices, which ensures a supportive school environment that will empower adolescents to grow and thrive.