AbstractIntroductionThe United States Centers for Disease Control and Prevention currently recommends HIV screening at least annually among sexually active gay, bisexual and other men who have sex with men (MSM), but only half report being tested in the past year in the United States. As HIV self‐test kits are becoming more available around the United States via web and app‐based interventions, it is important to understand who is willing and able to order them. This analysis sought to better understand predictors of free HIV self‐test kit utilization among MSM in M‐cubed, an HIV prevention mobile app intervention trial in Atlanta, Detroit and New York City.MethodsWe conducted an exploratory secondary analysis of self‐report and in‐app data collected from the intervention arm of the M‐Cubed study from 24 January 2018 to 31 October 2019. Behavioural, demographic and other potential predictors of HIV self‐test ordering were identified from Social Cognitive Theoretical underpinnings of the app, and from the literature. Significant predictor variables in bivariate analyses were considered for inclusion in the empiric multivariable model. Demographic variables chosen a priori were then added to a final model estimating adjusted prevalence ratios (aPR).ResultsOver half of the 417 intervention participants ordered an HIV self‐test kit during the study. In bivariate analyses, ordering a kit was associated with HIV testing history, plans to get tested and reported likelihood of getting tested. In the final model, participants were more likely to order a kit if they reported plans to get tested in the next 3 months (aPR = 1.58, 95% CI: 1.18–2.11) or had not tested for HIV in the past 3 months (aPR = 1.38, 95% CI: 1.13–1.70). There was no difference in HIV self‐test kit ordering by income, race/ethnicity or age.ConclusionsHIV testing is an important tool in ending the HIV epidemic and must be accessible and frequent for key populations. This study demonstrates the effectiveness of HIV self‐test kits in reaching populations with suboptimal testing rates and shows that self‐testing may supplement community‐based and clinical testing while helping overcome some of the structural barriers that limit access to annual HIV prevention services for MSM.