Recent studies suggest that people living with HIV with lower viral load are at reduced risk for transmitting HIV to their sexual partners. As information about the association between viral load and risk for HIV transmission disseminates throughout high-risk communities, viral load discussions may be used more often as a risk reduction strategy. The overall purpose of this study was to determine the frequency of viral load discussions and unprotected anal intercourse (UAI) in primary and casual sexual partnerships among men who have sex with men (MSM). An online survey was completed by 326 MSM (82% Caucasian, 62% college educated, 7% HIV-positive or thought they were HIV positive) in January 2011. Results showed that viral load discussions occurred in 93% of primary partnerships in which at least one partner was HIV-positive; UAI was reported with 46% of all primary partners and 25% of serodiscordant primary partners with whom viral load was discussed. Viral load discussions occurred in 53% of the three recent sexual episodes with casual sex partners with whom participants had either sex with once or had sex with multiple times in the past three months. UAI was more common in sexual encounters with casual sex partners when viral load was not discussed than when viral load was discussed (75% v. 56% of encounters). The finding that casual sexual episodes that did not include viral load discussions had a higher percentage of UAI than those that did include viral load discussions suggests either that men who do not discuss viral load may be higher risk-takers than men who do, or that the former are less adept at negotiating safer sex with casual sex partners than men who do discuss viral load. More research is needed to understand the role of viral load discussions in negotiating sexual activities among MSM.