Social media offer a wide range of advantages, but excessive usage can result in negative, psychological and behavioral consequences, including addiction. This study aims to explore the role of intentions of excessive social media usage in smartphone addiction. The analysis included data from 483 respondents who answered an online survey. The results showed that intentions of excessive social media usage can be grouped into four categories: social motivations, mode modification, productive reasons, and peer pressure. The results of multiple linear regression analysis revealed that the using social media excessively for mode modification and for peer pressure were significant predictors of smartphone addiction. Additionally, multivariate analysis of variance (MANOVA) indicated significant age groups differences in intentions of excessive social media usage for peer pressure and for productive reason. Emerging adults used social media excessively for peer pressure and productive reasons compared to adults. Conversely, a significant gender-related differences in intentions of excessive social media usage for mode modification and for social motivation. Females used social media excessively for mode modification and for social motivation compared to male. These findings enhance our comprehension of the factors impacting smartphone addiction and emphasize the role of intentions of excessive social media usage in its development, overcoming the limitation of the literature on screentime, which has paid limited focus to the purpose of use.