Background:
Iran is one of two main target markets for illicit tobacco trade in the WHO Eastern Mediterranean Region. Serial studies of Cigarette Packs Survey with same method were conducted in Tehran between 2003 and 2015 to evaluate consumed smuggled cigarettes.

Objective:
This study as the fourth Cigarette Packs Survey is designed to indicate the trends of illicit cigarette trade in Tehran in last two decades.

Methods:
This was a cross-sectional household study carried out in early 2021 in Tehran on 3042 smokers aged ≥15 years who reported smoking of at least one daily cigarette for a year. The sampling method was like the sampling method used in three previous studies. Participants were asked to reveal their current cigarette pack, which was either legal cigarettes (displaying governmental pictorial warning and hologram) or illegal cigarettes (with no governmental label).

Results:
The subjects included 2536 males (83.4%) and the mean age was 39.9±12.1 years; 1854 subjects (60.9%) showed foreign cigarettes and 1188 (39.1%) showed domestic cigarettes; 2705 (88.9%) consumed legal cigarettes and 337 (11.1%) consumed illegal cigarettes. Consumption of smuggled cigarettes was more by males (11.7% vs 8.1%). No significant differences were seen by marital status and education level in terms of illegal cigarettes prevalence.

Conclusions:
Compared with previous studies, the trend of consumption of illicit cigarettes has been decreasing in the past two decades. This could be due to new regulation on monitoring cigarette distribution and changing illegal brands to legal as joint production.