Objective To compare three groups of men who have sex with men (MSM)—men who had attended a sex party in the past year (45.2%); men who had been to a sex party more than a year ago (23.3%); and men who had never been to one (31.5%)—on socio-demographic and behavioural characteristics.

Method In spring 2012, 2063 sexually active MSM in the USA were recruited using banner advertising on a sexual networking website to complete an online survey about their sexual behaviour and attendance at sex parties.

Results A significantly higher proportion of past year attendees were HIV-positive (28.1%), single (31.7%), demonstrated sexual compulsivity symptomology (39.2%), recently used drugs (67.8%), averaged the greatest number of recent male partners (Mdn=15, <90 days), and had greater instances of recent unprotected anal intercourse (UAI) with male partners (median=3, <90 days). Adjusting for covariates, those having been to a sex party in the last year were significantly more likely than others to report UAI. Free lubricant (93.4%) and condoms (81.0%) were the most desirable services/products men wanted at sex parties. More than half of men having been to a sex party expressed interest in free rapid HIV testing at sex parties (52.8%); however, few considered it acceptable to see ‘medical providers’ (11.7%) and ‘peer outreach workers’ (9.5%) at sex parties.

Conclusions MSM who have attended a sex party in the last year are appropriate candidates for targeted HIV and sexually transmitted infection (STI) prevention. Collaborating with event promoters presents valuable opportunities to provide condoms, lubricant and HIV/STI testing.