Illicit cigarette trade in the greater metropolitan area of Costa Rica: a smokers' survey

Background Illicit cigarette markets are shaped as much by supply-side and enforcement factors as by consumer affordability. In Central America, a subregion that includes major transhipment points such as the Panama Canal, independent measurement of these structural features has been limited, and public debate has been shaped largely by industry-funded estimates. Methods We conducted a cross-sectional survey of 613 adult smokers in Costa Rica's Greater Metropolitan Area (November–December 2023) using a geographically stratified intercept non-probabilistic design with sex–age quotas. We classified each respondent's most recent purchase as licit or illicit through photographic pack inspection against a regulatory checklist and a pre-specified price-based rule for single sticks. We estimated penetration of illicit cigarettes in total consumption and prevalence of illicit purchasing. Results Illicit cigarettes accounted for 30.5% (95% CI 25.3–35.7) of total consumption; 20.3% of smokers reported an illicit most recent purchase. Pack-based purchases drove the estimate (27.5%); single sticks contributed 3.05%. Findings were relatively stable under price-threshold variation (29.8% at USD 0.12; 36.9% at USD 0.21). The illicit segment was concentrated (Herfindahl–Hirschman Index 0.306 vs 0.172 for the total market), dominated by three unregistered brands, with packs traced primarily to China and South Korea. Conclusions Illicit cigarette trade in the Costa Rican GMA is pack-driven and supply-concentrated. The pattern is consistent with organised transhipment supply chains rather than affordability-driven single-stick sales, supporting customs oversight and full implementation of the Protocol to Eliminate Illicit Trade in Tobacco Products.