Integration Doughnut or a Hole? Economic Effects of European Union Enlargement on its Eastern Member Countries 2001-2025

The European Union (EU) hails enlargement as one of its greatest successes, promising prosperity and convergence. Yet, two decades after the eastern enlargement, worthy economic results are evident, as well as cracks. While accession spurred growth and wealth, it also entrenched structural vulnerabilities – rising debt, demographic collapse and deepening internal disparities. The East was expected to catch up with the ‘old’ EU countries. GDP per capita has slowly converged, but much of it remains locked in a dependent model, with skilled labour flowing westwards, while financial obligations mount. Using a structured statistical analysis rather than econometric modelling, this paper exposes the uneven realities in the EU membership. Integration has lifted national economies, but widened gaps within them, concentrating wealth and opportunity in capital cities while rural and industrial peripheries lag. Meanwhile, the EU’s own cohesion is fraying, burdened by crises, militarisation, policy contradictions and enlargement fatigue. As candidate countries in the Western Balkans and the Black Sea region consider their EU future, important lessons emerge.