Social media addiction among youths is becoming a pressing public mental health issue in contemporary society due to the devastating consequences on individuals (i.e., perpetrator and victim) and society. This study, therefore, examined the prevalence, pathways to social media addiction, and predictive factors of social media addiction among Ghanaian youths. The present study used a cross-sectional survey design. A total of 488 participants were conveniently selected to respond to measures on social media addiction, gaming disorder, internet gaming disorder, smartphone application-based addiction, nomophobia, stress, anxiety, and depression. Linear regression and Hayes’ PROCESS macro were used to analyze the data. The findings revealed the prevalence rates of social media addiction (12.3%), gaming disorder (3.7%), internet gaming disorder (3.1%), smartphone application-based addiction (29.1%), nomophobia (49.6%), stress (26%), anxiety (62.1%), and depression (49%). There was a direct effect of smartphone application-based addiction on social media addiction and indirect effects through gaming disorder and nomophobia. Also, smartphone application-based addiction had direct effects on gaming disorder, internet gaming disorder, nomophobia, stress, anxiety, and depression. However, there was no direct effect of internet gaming disorder, stress, anxiety, and depression on social media addiction. Furthermore, smartphone application-based addiction and nomophobia (specifically, “losing connectedness” and “giving up convenience”) significantly predicted social media addiction among the youths in general. Among females, the predictive factors were smartphone application-based addiction, and nomophobia, specifically “losing connectedness” and “not being able to access information,” while smartphone application-based addiction, anxiety, and nomophobia, specifically “giving up convenience,” were the predictive factors for males. Smartphone application-based addiction and nomophobia play significant roles in social media addiction, and there are at least three pathways to social media addiction among youths. Therefore, counselors and health professionals need to develop educational and preventive programs that focus on digital literacy and healthy technology use among youths.