Full title: New insights in hidradenitis suppurativa from a population-based Dutch cohort: prevalence, smoking behaviour, socioeconomic status and comorbidities Summary Background Hidradenitis suppurativa (HS) is a chronic autoinflammatory skin condition and is associated with several comorbidities. Previous studies report variable prevalence rates of HS, depending on the methodology. However, the exact prevalence remains unknown. Objectives To estimate the prevalence of HS in a large population-based cohort in the Northern Netherlands, and to compare patients with HS to the general population, investigate characteristics and identify potential associated comorbidities. Methods Data were collected through a cross-sectional survey-based study within the Lifelines Cohort Study (n = 167 729), based on the general population located in the Northern Netherlands. A digital self-reported questionnaire was developed consisting of validated questions for determining HS. Results Among 56 084 respondents, the overall prevalence of HS was 2.1% [95% confidence interval (CI) 2.0–2.2]. The respondents with HS had lower socioeconomic status than the controls (P < 0.001) and more frequently currently smoked (P < 0.001). Several new significant associations in patients with HS were revealed, such as fibromyalgia (OR 2.26, 95% CI 1.64–3.11), irritable bowel syndrome (OR 1.63, 95% CI 1.18–2.26), chronic fatigue syndrome (OR 1.72, 95% CI 1.06–2.78) and migraine (OR 1.48, 95% CI 1.11–1.96). Fibromyalgia and chronic fatigue syndrome remained significantly associated with HS in the multivariate analysis after adjusting for age, sex, body mass index, smoking status and socioeconomic status. Conclusions Our study showed a higher prevalence of HS in the Northern Netherlands compared with the overall estimated prevalence of 1% and identified several new associated comorbidities. Open access, https://onlinelibrary.wiley.com/doi/10.1111/bjd.20954