OBJECTIVE Inequalities in alcohol-related harm may arise partly from differences in drinking practices between population groups. One underresearched practice associated with harm is consuming alcohol alone. We identify sociodemographic characteristics associated with drinking alone and the occasion-level characteristics associated with occasions when people drink alone.

METHOD A cross-sectional analysis of 1-week drinking diaries collected between 2015 and 2019 was conducted using event-level data on 271,738 drinking occasions reported by 83,952 adult drinkers in Great Britain. Our two dependent variables were a binary indicator of reporting at least one solitary drinking occasion in the diary week at the individual level and a binary indicator of drinking alone at the occasion level (event level).

RESULTS Individual-level characteristics associated with solitary drinking were being a man (odds ratio [OR] = 1.88, 95% CI [1.80, 1.96]), age greater than 50 years (OR = 2.60, 95% CI [2.40, 2.81]), not in a relationship (OR = 3.39, 95% CI [3.20, 3.59]), living alone (OR = 2.51, 95% CI [2.37, 2.66]), and being a high-risk drinker (OR = 1.54, 95% CI [1.52, 1.59]). Occasion-level characteristics associated with solitary drinking were that they were more likely to occur in the off-trade (OR = 3.08, 95% CI [2.95, 3.21]), Monday-Thursday (OR = 1.36, 95% CI [1.27, 1.47]), and after 10 P.M. (OR = 1.36, 95% CI [1.27, 1.47]) controlling for geographic region and the month the interview took place.

CONCLUSIONS Characteristics of solitary drinking largely align with characteristics we associated with drinking problems. Those who partake in at least one solitary drinking occasion are overall more likely to consume alcohol at risky levels; however, the number of drinks consumed on each occasion was lower during a solitary drinking occasion.