This study examines the prevalence and determinants of smartphone addiction (SA) in a sample of 825 Muslim secondary school students from three provinces along the southern border of Thailand. Employing purposive sampling, the research highlights a concerning 70% rate of SA, surpassing the rates observed in other Asian demographics. The investigation reveals a robust link between parental education levels and smartphone usage among adolescents. Utilizing a structural equation model (SEM), family functioning dimensions such as ‘Emotional Status’ and ‘Discipline’ are shown to have a considerable impact on SA. Contrary to expectations, enhanced ‘Family Support’ has emerged as a potential risk factor, suggesting nuances in family dynamics that may contribute to SA. The findings advocate for the reinforcement of family functioning and call for initiatives to improve digital literacy and foster open communication between parents and children. However, the reliance on self-reported measures and the cross-sectional nature of the study underlines the necessity for more expansive future research to validate these findings and explore underlying mechanisms.