Female sex workers (FSWs) can receive a premium for engaging in unprotected and other risky sexual behaviours. Women engaging in transactional sex, defined as 'non-commercial sexual relationships motivated by the implicit assumption that sex is exchanged for material support', are thought to share similar economic incentives as women engaging in commercial sex. Using a panel of up to six sex acts from longitudinal datasets stratified by FSWs and women engaging in transactional sex in Cameroon, we provide evidence consistent with literature of a 30% condomless risk premium for FSWs. We then provide the first empirical evidence of a discount for condomless sex of 14% for women engaging in transactional sex. Qualitative analysis offers two explanations for this surprising finding, first a lack of HIV awareness among women engaging in transactional sex, and second, that risky sex acts are a demonstration of investment of trust in relationships and represent unobservable exchange of value. Given the larger number of women engaging in transactional relationships compared to FSWs in sub-Saharan Africa, and their lower awareness of HIV risks, this finding offers a significant explanation for the disproportionate burden of HIV incidence among adolescents and young women in sub-Saharan Africa.