BackgroundGlobally female sex workers (FSWs) are vulnerable to violence from intimate partners, police and clients due to stigma and criminalisation. In this paper we describe South African FSWs' exposure to violence and factors associated with having been raped in the past year. MethodsWe conducted a multi-stage, community-centric, cross-sectional survey of 3005 FSWs linked to sex worker programmes in 12 sites across all nine provinces that had a SW programme. Adult women who sold sex in the preceding six months were recruited for interviews via sex worker networks. Survey tools were developed in consultation with peer educators and FSWs. ResultsIn the past year, 70.4% of FSWs experienced physical violence and 57.9% were raped: by policemen (14.0%), clients (48.3%), other men (30.2%) and/or and intimate partner (31.9%). Sexual IPV was associated with food insecurity, entering sex work as a child, childhood trauma exposure, post-traumatic stress disorder (PTSD), drinking alcohol to cope with sex work, working more days, partner controlling behaviour, having an ex-client partner, and having no current partner to protect from ex-partners. Rape by a client, other men or policemen was associated with food insecurity, childhood trauma, PTSD, depression, using alcohol and drugs, being homeless or staying in a sex work venue, selling sex on the streets, working more days and having entered sex work as a child and been in sex work for longer. ConclusionSouth African FSWs are very vulnerable to rape. Within the social climate of gender inequality, sex work stigma, criminalisation, and repeated victimisation, the key drivers are structural factors, childhood and other trauma exposure, mental ill-health, circumstances of sex work and, for SIPV, partner characteristics. Mostly these are amenable to intervention, with legislative change being foundational for ending abuse by policemen, enhancing safety of indoor venues and providing greater economic options for women.