BACKGROUND: Despite evidence that many people engage in solitary drinking and that it might be associated with negative consequences, to date, little research has focused on this form of drinking behaviour. This study examined the prevalence and factors associated with solitary drinking, and assessed whether it is linked with hazardous alcohol use among males in nine countries of the former Soviet Union (fSU). METHODS: Data came from a cross-sectional population-based survey undertaken in 2010/11 in Armenia, Azerbaijan, Belarus, Georgia, Kazakhstan, Kyrgyzstan, Moldova, Russia, and Ukraine. Information was obtained on the frequency of solitary drinking among male regular drinkers (i.e., those consuming alcoholic drinks at least once a month), and on problem drinking (CAGE) and heavy episodic drinking (HED). Logistic regression analysis was used to examine associations between the variables. RESULTS: The prevalence of occasional and frequent solitary drinking ranged from 8.4% (Georgia) to 42.4% (Azerbaijan), and 3.1% (Kazakhstan) to 8.2% (Armenia), respectively. Solitary drinking was associated with being older, divorced/widowed, living alone, having a bad/very bad household financial situation, lower levels of social support, and poor self-rated health. Occasional solitary drinking was linked to problem drinking and HED, while frequent solitary alcohol use was related to problem drinking. CONCLUSIONS: Solitary drinking is relatively common among male regular drinkers in the fSU and is linked to older age, social and economic disadvantage, and hazardous alcohol use.