Progress in reducing tobacco use is a key indicator for measuring countries’ efforts to implement the WHO Framework Convention on Tobacco Control – target 3.a under the Sustainable Development Goals agenda. Countries have adopted this indicator to report progress also towards the tobacco reduction target under the Global Action Plan for the Prevention and Control of Noncommunicable Diseases 2013–2020 and the WHO’s Global Programme of Work triple billions target. This report presents WHO estimates of tobacco use prevalence for 2020, numbers of users, and trends projected to 2025. Estimates are at global, regional and country-level.