The present study explored links between male Dark Tetrad personality traits (psychopathy, Machiavellianism, narcissism, sadism) and preferences for using outdoor and indoor female sex worker services. We also investigated the mediating effects of perceiving sex workers as deviant and as victims. Heterosexual males (N ¼ 347) were recruited to take part in an online survey investigating personality and attitudes towards female sex workers. Path analyses revealed that psychopathy and sadism positively predicted preferences for outdoor but not indoor female sex services. Sex worker choice mediated positive links between narcissism and outdoor female sex worker preferences. Compared to indoor, outdoor sex services are associated with increased aggression and violence. Our findings highlight the importance of considering narcissism and particularly psychopathy and sadism when investigating individual male preferences for outdoor sex services that are being offered by particularly vulnerable women.