With the exponential increase in the number of social networking sites (SNS) users, there is also a significant shift in the popularity of these SNS. Moreover, fear of missing out (FOMO) is often blamed for the growth in SNS addictive tendencies. The current research examines the influence of FOMO and Big 5 personality traits on SNS attitudes, usage, and addictive tendencies in the context of an increasingly popular SNS – Instagram. Participants completed online questionnaires that assessed their personality traits and then be-friended one of the researchers on Instagram, which provided the actual Instagram activity data (e.g., total number of Instagram posts, total number of likes, etc.). Hierarchical regression results showed that personality factors explained significant amounts of variance in terms of attitude towards Instagram, number of likes, total number of Instagram posts since account inception, and social media addictive tendencies. Furthermore, FOMO had a significant positive effect on attitude toward Instagram, the total number of Instagram accounts that respondents followed, and social media addictive tendencies.