This study used expectancy violations theory and uses and gratifications theory to conduct an experiment investigating how the content of relationship initiation messages, recipients’ gender, and recipients’ motives for using online dating applications shape whether and how the initiation message violates recipients’ expectations. Participants (N = 275) were recruited through an emergent adult population at a large Midwestern university and identified primarily as women (66.7%), heterosexual (79%), and white (64.5%). Participants were randomly assigned to imagine matching with someone through online dating who sent either a traditional greeting or sexually explicit content in their initial message. As predicted, receiving a sexually explicit message was more unexpected and perceived more negatively than receiving an ordinary greeting, but the intensity of that negative reaction was moderated by users’ motives for using online dating apps and gender. Negative reactions to receiving sexually explicit content were amplified for women and individuals interested in long-term relationships. Negative reactions were dampened for men and online daters interested in casual sexual relationships. The implications of the findings are discussed in relation to expectancy violations theory and research on relationship initiation in online contexts.