Objectives To assess the proportion of independent indoor female sex workers (FSW) in West Yorkshire, UK who advertise unprotected sex, and to investigate any association with cost, location and provision of anal sex.

Methods Data on whether independent indoor FSW (defined as those not advertising via an escort agency or through a parlour) advertised unprotected sexual services, along with demographic data, were collected from 462 advertisement profiles of FSW in West Yorkshire from the website http://www.adultwork.com. Independent t test and χ² statistics were used to test the association between advertised unprotected vaginal and oral sex, and FSW age, cost of services, location and whether they advertised anal sex.

Results Unprotected vaginal sex was advertised by 8% of FSW, and unprotected oral sex by 74% of FSW. FSW advertising unprotected vaginal sex were more likely to live in Wakefield and Bradford than in Leeds, had significantly lower hourly rates, and were more likely to advertise anal sex.

Conclusions Advertised condom use for vaginal and oral sex by independent indoor FSW in West Yorkshire was significantly lower than reported rates of protected sex found in previous studies based in London and the south of England. The advertisement of unprotected vaginal sex is associated with factors such as lower hourly rates and the advertisement of higher risk anal sex, which may signify greater economic need. FSW offering unprotected sex therefore represent an at-risk target group for health promotion.