|Due to a cultural shift, the lifetime number of sex partners and sexual satisfaction are growing topics of interest. However, research on the direct association between these factors is rare and inconsistent. The current cross-sectional study aims to examine whether there is an association between the lifetime number of sex partners and being sexually satisfied, with gender, the current relationship status and approach- and avoidance sexual motivations as possible moderators of this association. Furthermore, the role of self-esteem within this relationship is investigated. As part of the study ‘Seks onder je 25e’, a survey was conducted among 9,652 heterosexually identified, sexually active, Dutch 18–24 year-olds (M = 21.07 SD = 1.97). Regression analyses revealed that there was no direct association between the lifetime number of sex partners and sexual satisfaction. Gender and relationship status did moderate the association between the lifetime number of sex partners and sexual satisfaction, but approach- and avoidance motivation and self-esteem did not. There was a negative association for women and a positive association for men between the lifetime number of sex partners and sexual satisfaction. Moreover, in contrast to people with a relationship, single people reported to be more sexually satisfied when having had more sex partners. The results are discussed in light of traditional gender norms.