Alcohol prices are a powerful instrument for alcohol policymakers for impacting alcohol consumption and related harms 1. In the policymaker's toolkit, the main tool for increasing alcohol prices has been taxation, with the implicit assumption that taxes are passed through to prices. The conditions and boundaries of this assumption have been studied surprisingly little, and the study by Ally et al. 2 is a welcome contribution. In the study, the pass-through rates are examined by product type and price category in the United Kingdom, and the results show that in connection with tax increases, the prices of cheaper—higher–selling—products are raised less than the prices of more expensive products. This has implications for how an increase in alcohol excise duties may be expected to affect consumption, and hence harms, in various consumer groups. This is particularly relevant from the viewpoint of addressing increasing socio-economic disparities in alcohol-related harm. Socio-economic disparities in overall mortality and morbidity are large whether measured by educational, occupational or income differences 3, 4, and in many countries in Europe and the United States these disparities have grown considerably over the past decades 5, 6. For example, in the United Kingdom, men in the highest occupational category were, at the beginning of the 2000s, expected to live 5.8 years and women 3.5 years longer than men and women in the lowest occupational category, which is a considerable increase from the difference of 4.9 years and 2.3 years observed 20 years earlier 7. Closing these gaps has been identified as one key health challenge within the European Union 8. Socio-economic disparities in alcohol-related mortality are also high, and often even higher than those for overall mortality 9, 10. This has not always been the case, however. In England and Wales the relative index of inequality in male liver cirrhosis mortality by social class rose from 0.88 [lower mortality in lower socio-economic status (SES) categories] in 1961 to 1.4 (higher mortality in lower SES categories) in 1981, and an even stronger shift was reported for men in Scotland (from 0.6 to 1.67) 11. Since then, alcohol-related mortality in the United Kingdom has increased even further 12, and at the beginning of the 2000s, alcohol-related mortality was reported to be 3.5 greater in the routine occupational class compared to the higher and managerial occupations among men, and 5.7 times greater among women 10. In this same period, with increasing alcohol-related mortality and mortality differentials, the price of alcohol has fallen relative to personal disposable income 13, 14, which has meant that consumption habits leading to liver cirrhosis and other alcohol-related diseases are increasingly within the reach of everyone. From Finland, there is more direct evidence that alcohol has played a central role in the increasing inequalities in overall mortality 9. It is extremely important to prevent severe alcohol-related harm in the lower socio-economic groups, where the burden is the greatest. The price of alcohol is particularly relevant in this group, making it a useful tool. Against this background, Ally et al.'s results are highly important. It is known that heavier drinkers and particularly heavy drinkers with lower incomes tend to purchase cheaper alcohol 15. Ally et al. show that it is exactly in this cheapest price category where increased taxes are not passed through to prices. In other words, commercially operated companies are unwilling to increase the price of the alcoholic beverages for which this would be most important from a public health viewpoint, i.e. the cheapest alcohol which is bought and consumed in greatest quantities, by the heaviest drinkers, and hence lead to most harm. This renders tax increases less efficient from the public health viewpoint than they would be with an evenly distributed tax pass-through. Minimum unit pricing would in this case be an ideal supplement, a targeted measure, which would have little impact on moderate drinkers, even those with low incomes 15. Minimum unit pricing would therefore be highly justified as an efficient method to combat harmful drinking and to reduce alcohol-related harm and its high socio-economic disparities. None.