BackgroundSedentary behaviour (SB) has been linked with detrimental effects on morbidity and mortality. This study aims to identify the individual, social and environmental correlates of total sedentary behaviour and the contexts in which sitting time accumulates in an Irish adult cohort.MethodsCross-sectional analysis of data from 7328 adults of the nationally representative Healthy Ireland Survey. Ordinal regression analyses were used to examine participants’ socio-demographic characteristics, lifestyle factors, physical and mental health status, perceived neighbourhood environmental factors, and their association with total daily sitting times and sitting times across the domains of occupation, leisure screen-time and transportation/leisure.ResultsOverall median of sitting time per day was 450 min (7.5 h). Male gender, and living in an urban location were associated with increased total-, occupational, and screen-time sitting (p < 0.001). Younger age was associated with increased total and occupational sitting times (p < 0.001), while being older was associated with increased screen-time and transportation/leisure sitting (p < 0.001). Insufficient physical activity levels were associated with increased sitting across all domains (p < 0.001). Higher socio-economic classification and education levels were associated with increased total, occupational, and transportation/leisure SB (p < 0.001), while lower socio-economic classification and education levels were associated with increased screen-time sitting (p < 0.001). Alcohol consumption was associated with screen-time and transportation/leisure sitting (p < 0.01), while smoking was associated with increased screen-time sitting (p < 0.001). Being married was associated with less screen-time (p < 0.001) and transportation/leisure sitting (p = 0.02), while those with a caring role had less total (p = 0.04) and screen-time sitting (p = 0.01). A significant negative association between neighbourhood attributes and total (p = 0.04), and transportation/leisure sitting times (p < 0.001) was found.ConclusionThe results of this study provide a starting position for development of targeted interventions aimed at the most sedentary, such as males with sedentary occupations in higher socio-economic groups and education levels, those with insufficient levels of physical activity and who live in an urban location.