Objectives The vast majority of tobacco users began before the age of 21. Raising the tobacco sales age to 21 has the potential to reduce tobacco use initiation and progression to regular smoking. Our objective was to assess the level of public support nationally for ‘Tobacco 21’ initiatives in the USA.

Methods The Social Climate Survey of Tobacco Control, a cross-sectional dual-frame survey representing national probability samples of adults was administered in 2013. Respondents were asked to state their agreement level with, ‘The age to buy tobacco should be raised to 21.’

Results Of 3245 respondents, 70.5% support raising the age to buy tobacco to 21. The majority of adults in every demographic and smoking status category supported raising the tobacco sales age to 21. In multivariable analyses, support was highest among never smokers, females, African-Americans and older adults.

Conclusions This national study demonstrates broad public support for raising the sales age of tobacco to 21 and will help facilitate wide dissemination of initiatives to increase the legal purchase age at national, state and local levels. Increasing public awareness about the susceptibility and rapid addiction of youth to nicotine may further increase public support for raising the tobacco sale age to 21.