Why environmental taxation fails to converge in the European Union: Evidence of structural divergence across the EU 27

Research background: Environmental taxation is a foundational pillar of the European Union’s strategy for climate neutrality and sustainable development. However, its implementation across Member States remains uneven and structurally fragmented, raising questions about the effectiveness of policy harmonization. Purpose of the article: This study provides a longitudinal, comparative analysis of environmental tax structures from 1995 to 2022 in the EU‑27, with a special focus on Slovakia, the V4 countries, and Romania. Methods: Using Eurostat data and a mixed-methods statistical approach, including point estimates, General Linear Models, and repeated-measures ANOVA with post hoc testing, we examine four tax categories: total environmental, energy, transport, and pollution/resource taxes. Findings & value added: The results show that environmental taxation in the EU does not move toward a single model but instead follows different paths shaped by fiscal integration, institutional capacity, and political feasibility. These findings challenge the common belief that policy harmonization causes convergence in environmental taxation across Member States. The prominence of energy taxes, along with the ongoing underuse of transport and pollution/resource taxes, presents a structural barrier to achieving environmental policy goals. Notable regional differences are seen, especially in post-socialist economies, where environmental taxation is more affected by fiscal and institutional limitations than environmental priorities, with agriculture as a key blind spot. By implementing a region-sensitive environmental taxation framework, this study advances environmental tax theory by viewing environmental taxation as a context-dependent policy system rather than a universally applicable tool. The findings contribute to ongoing discussions on green fiscal reform by showing that convergence requires more integration of taxation with environmental goals and supporting policy measures. The results support adaptive reforms targeted at rebalancing tax systems, broadening sectoral coverage, and increasing fiscal resilience in response to changing sustainability objectives, with relevance extending beyond the EU to other diverse policy environments.