Introduction:
The availability of lower-cost cigarettes provides price-sensitive smokers with incentives to purchase cheaper cigarettes in order to minimize their financial costs of continuing to smoke. This study estimates the prevalence of and factors associated with cross-border purchasing of cheaper cigarettes among nationally representative samples of smokers from Germany, Greece, Hungary, Poland, Romania, and Spain (n = 6,011).

Material and Methods:
The primary outcome was purchasing cheaper out-of-country cigarettes in the last six months. The prevalence of cross-border purchasing was estimated by country and residential location, defined as (a) living in regions bordering a country where the cost of the most popular price category brand of cigarettes was at least €1/pack lower than in smokers' home countries, (b) living in regions bordering a country with similar cigarette prices, and (c) living in regions not bordering other countries. Weighted multivariable logistic regression tested differences in purchasing cheaper out-of-country cigarettes by country and residential location.

Results:
Residential location was associated with purchasing cheaper out-of-country cigarettes in Germany and Poland (p < 0.05): 31% of German and 11% of Polish smokers living in regions bordering lower-price countries made such purchases in the last six months. Across all countries, smokers living in areas bordering lower-price countries had 4.21 times greater odds of purchasing cheaper out-of-country cigarettes compared to smokers living in non-border areas (95% CI: 2.39-7.42).

Conclusions:
Tax harmonization policies that minimize cross-border price differentials can eliminate lower-priced alternatives for price-sensitive smokers.