This study aims to estimate the prevalence and dual use of cigarettes, heated tobacco products (HTPs) and electronic cigarettes (e-cigarettes) among individuals aged 18–24 in Japan.

This cross-sectional study involved a door-to-door survey administered by trained interviewers using a structured questionnaire.

Individuals aged 18–24 residing in 220 areas within 10 ordinance-designated cities (Sapporo, Sendai, Saitama, Chiba, Yokohama, Kawasaki, Sagamihara, Nagoya, Osaka and Fukuoka) as well as Tokyo’s 23 wards in Japan in 2019 were included.

A total of 1738/5500 individuals were included in the analysis, with participants evenly distributed by sex, age and residential area.

Cigarette, HTP and e-cigarette use was assessed.

The weighted prevalence of the current use of cigarettes, HTPs and e-cigarettes accounted for 10.1% (95% CI 8.7, 11.5), 5.1% (95% CI 4.1, 6.1) and 1.8% (95% CI 1.2, 2.4), respectively. Approximately 68.2% of the people who used HTPs at the time were dual users of both HTPs and cigarettes. There was a significant gap in tobacco product use between individuals aged 20–24 and those aged 18–19, with this difference remaining after adjusting for covariates.

In 2019, cigarettes were the most used tobacco-related product among young adults in Japan. Smoking initiation appears to notably increase at age 20 when smoking becomes legal in Japan. The prevalence of HTP use among young adults in Japan is notably higher than in other countries.