Barebacking, or intentional unprotected anal intercourse (UAI), among men who have sex with men (MSM) has been a growing concern for the public health community because of UAIs link to HIV incidence and sexually transmitted infections (STIs). Men who bareback have created online spaces through websites that host thousands of profiles throughout the US and world. Adapting two domains from person-environment theory, this study contrasted the health messages surrounding the risks of UAI within two mainstream US-based barebacking websites. One website developed intensive systems to promote harm reduction, such as encouraging frequent HIV-testing, discussing STIs with partners, and limiting the number of partners. In contrast, the other site analysed negated the seriousness of HIV and STIs, which can have clear negative outcomes for patrons whom relied on this information. This analysis implicates the need to explore electronic environments as viable tools for HIV prevention and programme development.