In the United States (US), sexuality-based stigma continues to undermine HIV prevention and care efforts. We assessed sexual behavior stigma burden across family, healthcare, and social domains and determined associations with HIV-related outcomes among cisgender gay, bisexual, and other men who have sex with men (MSM) in nine US metropolitan statistical areas. MSM ( = 4,086) recruited at places of MSM social congregation via venue-based, time-sampling procedures completed a survey on sexual behavior stigma, PrEP (pre-exposure prophylaxis) continuum and HIV care continuum outcomes, sociodemographic characteristics, and other measures. We calculated prevalence and overall mean stigma subscale scores (range: 0.00-1.00) and used logistic and mixed effects logistic regression to determine stigma-HIV outcome associations. Most participants identified as gay, were employed, and were from West Coast cities; roughly 40% were non-Hispanic white, aged 25 to 34 years, and had completed some college. One in five were living with HIV. Family stigma (prevalence = 47.5%; mean = 0.36) was associated with greater odds of healthcare engagement, PrEP awareness, and PrEP use among HIV-negative MSM. Anticipated healthcare stigma (prevalence = 14.5%; mean = 0.11) was associated with lower odds of healthcare engagement, current ART (antiretroviral therapy) use, and viral load undetectability among MSM living with HIV. General social stigma (prevalence = 49.9%; mean = 0.20) was associated with greater odds of PrEP awareness and use among HIV-negative MSM and lower odds of current ART use among MSM living with HIV. Targeted stigma-mitigation in family, healthcare, and other social contexts remains paramount to ending the HIV epidemic in the US.