Today, young people spend much of their lives online where they encounter abundant appearance-focused content. In light of the important role that social media platforms like Instagram play in young people's attitudes towards the cosmetic surgery industry, this study investigates passive and active social media usage in relation to young adults’ perceptions of cosmetic procedures. In a cross-sectional survey study among 470 Instagram users aged 18–25 years (Mage = 21.00, SDage = 2.26), young adults indicated a low cosmetic procedure intention themselves, but overestimated the prevalence of cosmetic procedures undertaken by others. Considering passive social media use, young adults who follow influencers who had undergone cosmetic procedures reported higher intentions to have cosmetic procedures themselves, and following influencers who had not undergone procedures was related to lower intentions. In terms of active social media usage, frequency of Instagram posting was generally insignificant in relation to acceptance of and intention to undergo cosmetic procedures. Yet, those who used filters to edit pictures more frequently reported increased cosmetic procedure acceptance and intention. Overall, this paper offers a nuanced perspective on the relation between young adults’ perceptions of cosmetic procedures and their social media behaviors, highlighting the importance of specific appearance-oriented social media usage.