The many faces of carbon tax regressivity—Why carbon taxes are not always regressive for the same reason

Carbon taxes can be regressive for multiple reasons. Differences in what households consume, the carbon-intensive of what they consume, the technology they use, and how much of their income they spend all contribute towards the regressivity of a carbon tax. This paper quantifies the relative importance of these factors for carbon tax regressivity in 6 EU countries. The comparison across countries highlights that differences in what households consume are important, but not always the most important factor in driving carbon tax regressivity. Differences in how much of their income households spend are always important and often the most important factor. Differences in the carbon intensity of consumption are more relevant in Eastern European countries and the importance of heating and transportation technology depends on the country. This paper concludes with implications for designing effective mitigation strategies and cross-country policy transfer, highlighting that the source of carbon tax regressivity and effective strategies differs across countries. • The main drivers of carbon tax regressivity differ across countries. • Differences in budget shares are important but rarely the most important factor. • Differences in the carbon intensity of consumption are more important in poorer countries studied. • Differences in savings rates are always important, but most in wealthier countries studied. • Effective strategies to mitigate carbon tax regressivity are country-specific.