Hooking up is defined as a physical encounter between two people who are not romantically committed. This study explored whether there were subgroups of young adults with unique reactions to hooking up (N = 879). Psychosocial predictor variables (gender, depression, loneliness, intoxication level, college adjustment, and hope for a committed relationship) were investigated along with emotional reactions as the outcome variables. Through the use of cluster analysis, four distinct clusters were identified: Happy Hopeful, Content Realist, Used and Confused, and Disappointed and Disengaged. The majority (62 %) of the sample reported mostly positive reactions to hooking up and fell within the Happy Hopeful or Content Realist clusters. Protective factors in these two clusters included hope for a committed relationship, having realistic expectations, and healthy psychological adjustment. The Used and Confused and Disappointed and Disengaged clusters reported the most negative hooking up reactions and consisted of 38 % of the overall sample. These two groups reported increased depression and loneliness symptoms and lower levels of social adjustment as compared to those clusters with more positive reactions.