Objective To inform public health approaches for chronic disease prevention, the present study identified sociodemographic, anthropometric and behavioural correlates of work, transport and leisure physical inactivity and sitting time among adults in Oman. Design Cross-sectional study using the WHO STEPwise study methodology. Setting Sur City, Oman. Subjects Men and women aged 20 years and older (n 1335) in the Sur City Healthy Lifestyle Study who had complete data for demographic variables (gender, age, education, work status and marital status), BMI and behavioural risk factors-smoking and dietary habits plus physical inactivity and sitting time (the outcome variables). Results The highest level of physical inactivity was in the leisure domain (55·4 %); median sitting time was about 2 h/d. Gender-stratified logistic regression models found that the statistically significant (P < 0·05) correlates of inactivity (in one or more domains) were age, work status and fruit and vegetable intake in women, and age, education, work status, marital status and BMI in men. Gender-stratified linear regression models found that the statistically significant correlates of sitting time were age, work status and BMI in women and education in men. Conclusions Findings suggest that public health interventions need to be gender responsive and focus on domain-specific physical inactivity. In the Omani context, this might include gender-segregated exercise facilities to promote leisure physical activity among women and walking-friendly environmental initiatives to promote transport physical activity among men. Further evidence on barriers to physical activity and factors that influence prolonged sitting is required to develop relevant public health interventions.