Introduction There is mixed evidence regarding the associations between self-esteem and smoking and excessive alcohol consumption. This study aimed to investigate whether self-esteem is associated with smoking status and alcohol consumption in a large sample of adults in the United Kingdom after adjusting for age, sex, socio-economic status and depressed mood. Methods Design: Cross-sectional correlational study conducted under the aegis of the British Broadcasting Corporation (BBC) between 2009 and 2013. Participants: 187,398 respondents (67.9% female) with a mean age of 32.82 years (SD=12.41) providing complete data. Setting: UK. Measures Online self-report questionnaire. The outcomes were smoking status (current smoker, ever smoker) and alcohol consumption (current drinker, excessive drinker); the input variable was self-esteem measured using a Single Item Self-Esteem Scale; covariates were age, sex, SES, and depressed mood measured using a single item question. Results The odds of being an ever smoker and a current smoker were greater in people with lower self-esteem (AdjOR 0.97; 95% CI 0.95-0.99, Cohen’s d=-0.02; and AdjOR 0.96; 95% CI 0.94-0.99, Cohen’s d=-0.02 respectively). The odds of being a current drinker were lower in people with lower self-esteem (AdjOR 1.20, 95% CI 1.17-1.24, Cohen’s d=0.10) while being an excessive drinker was associated with lower self-esteem (β=-0.13, p<0.001, F(5,187392)=997.14, p<0.001, Cohen’s d=0.3). Conclusions Lower self-esteem appears to be positively associated with ever- and current smoking and excessive alcohol consumption and negatively associated with current alcohol consumption.