Abstract Background and objective Smoking is recognised as a critical public health priority due to its enormous health and economic consequences. Constant monitoring of the effectiveness of tobacco control programs calls for timely population-based data. This study reports the national and sub-national patterns in tobacco consumption among Iranian adults based on the results from the STEPwise approach to chronic disease risk factor surveillance (STEPS) survey 2021. Methods This study was performed through an analysis of the results of the STEPS survey 2021 which had been conducted as a nationally representative cross-sectional study. Participants included Iranian adults aged ≥ 18 years in all provinces of Iran, who were selected via multistage cluster sampling method. Data were analyzed via survey analysis while considering population weights. Results The total number of participants was 27874, including 15395 (55.23%) women and 12479 (44.77%) men. The all-ages prevalence (95% CI) of current tobacco smoking was 14.01% (13.56–14.48): 4.44% (4.09–4.82) among women and 25.88% (25.03–26.75) among men. The all-ages prevalence of current cigarette smoking was 9.33% (8.95–9.72): 0.77% (0.62–0.95) among women and 19.95% (19.17–20.75) among men. The all-ages prevalence of current hookah smoking was 4.5% (4.23–4.78): 3.64% (3.33, 3.98) among women and 5.56% (5.12–6.03) among men. The mean (SD) number of cigarettes smoked per day among current cigarettes smokers was 11.4 (9.82): 5.9 (6.76) among women and 11.65 (9.87) among men. The mean (SD) monthly times of hookah use was 23.87 (44.95): 29.93 (48.26) among women and 19.02 (41.52) among men. The national all-ages prevalence of second-hand smoking at home was 24.65 (24.06–25.25): 27.39 (26.6-28.19) among women and 20.28 (19.4-21.18) among men. The national all-ages prevalence of second-hand smoking at work was 20.73% (20.11–21.36): 17.96% (17.21–18.73) among women and 25.15% (24.07–26.26) among men. Conclusion The tobacco consumption in Iran remains alarmingly high, indicating the current tobacco control policy implementation level is ineffective and insufficient. This calls for adopting, implementing, and enforcing comprehensive packages of evidence-based tobacco control policies.