Social media addiction has become an increasingly prevalent phenomenon among university students and has been associated with various academic, emotional, and social outcomes. However, previous studies have primarily focused on academic performance and psychological distress, while limited attention has been given to different dimensions of student engagement, particularly peer and teacher engagement. Therefore, this study aimed to examine the relationship between social media addiction and academic engagement, affective engagement, peer engagement, and teacher engagement among undergraduate students from private universities in Makassar, Indonesia. This study employed a quantitative cross-sectional design involving 129 students selected through simple random sampling. Data were collected using adapted versions of the Smartphone Application-Based Addiction Scale (SABAS) and the Higher Education Student Engagement Scale (HESES). The instruments were translated and adapted into Indonesian, and data were collected through an online questionnaire. Structural Equation Modeling–Partial Least Squares (SEM-PLS) using SmartPLS 4 was employed to analyze the relationships among variables. The results indicated that social media addiction was significantly associated with academic engagement. In contrast, no significant relationships were found between social media addiction and affective engagement, peer engagement, or teacher engagement. These findings suggest that the influence of social media addiction may vary across different dimensions of student engagement and is not uniformly detrimental. The study contributes to the literature by integrating multiple engagement dimensions within a single model and highlights the importance of considering the educational context when examining the consequences of social media addiction. Practical implications include the need for universities to promote digital literacy and responsible social media use while supporting broader aspects of student engagement.