The 2004 EU Enlargement: A Blueprint for Future Success

The EU enlargement of 2004: a success story to be built upon Isn’t this an opportune moment in 2025, when Poland takes over the presidency of the Council of the EU? Let’s reflect on the successes in history which somehow connected the 2004 enlargement to various important developments happening in this general region of the globe. It provides a clear illustration of how constructive joining and regarding membership as the beginning of deep reform can deliver benefits to the EU. In this connection, Poland, being now the sixth-largest economy in the EU, can claim having yielded overall benefits from membership and deep reform undertaken by the state. In 2004, Poland was one of nine new members of the EU from the Czech Republic, Cyprus, Estonia, Hungary, Latvia, Lithuania, Malta, Slovenia, and Slovakia that made up that year’s largest single intake in the Union, including around 20% or 75,000,000 people in total of those currently EU-condemned states. The effects of the enlargement within the EU could not be more critical and irrevocable.

Recall, in that perspective: As former states, such as Albania, Bosnia and Herzegovina, Kosovo, Montenegro, North Macedonia, Serbia, Georgia, Moldova, Ukraine, and Türkiye, stride or slide toward their future in a seemingly straightforward setting towards EU full membership, the 2004 enlargement serves as a concrete lesson learned by both potential and existing peoples in the prospective future expansions of the Union.
Economic Effects of the 2004 Enlargement
The most important economic fact is that the countries that participated had impressive growth, evidenced by data from available studies of the International Monetary Fund (IMF). The per capita Gross Domestic Product (GDP) in the new member states was on an average 30% higher after 15 years of EU membership than it could have been if it had not been the case. These dead statistics of national development reveal that future integration into European economies is gaining new ground.
Key drivers of these gains were several factors:
Reforms before the Accession: The new member-states undertook, before joining the European Union, these wide-ranging and, also in comparison to the EU membership-aspiring regions, much more far-reaching than liberalizing trade and reforming the financial sector and product markets. These reforms were carried out at a much broader and intensified rate. Given the new state-led or non-market-oriented economic regulation adopted during the transition, it was difficult for the EU to accept the policies of economic liberals during accession negotiations. At the same time, these structural changes transformed economies into promotional agents of their competitiveness while preparing them for integration under the single market of the European Union.
During the majority of the last two decades, the advanced countries of Central and Northern Europe enjoyed variety and contributed as much as they had of shared activities such as EU flag membership, institutional design of budgets, civil and social behavior norms, currency areas, military alliances, vertical as well as horizontal activities in terms of collaboration.
Since the end of the cold war, one finds two oppositely defined Eastern Europe dimensions with respect to future EU membership in Eastern Europe. The first grouping included the countries of Central Europe, whose priority aim was membership in the EU, while the second group, composed of the EFTA countries, envisaged a different primary aim, that of acquiring the principles and rules of the single market in the Union.
Following the collapse of the Soviet Union, this alleviated one burden of economic carrots and sticks as it could not now compete economically at the highest level. The joining of the European Union followed within 10 years of the collapse of the Soviet Union.
Benefits for Euro Members: Before and After Enlargement
Indeed, establishing the enlargements in the same way benefited not only new member countries, but also very recently existing member countries got very tangible economic gains by way of enlargements. It was around 2019: the per capita income for an established EU country would have been about 10% higher without the enlargement. Primarily, the single market has been enlarged with benefits as new member states can provide a much larger market where these companies could attract more consumers and business firms; remain up in mass production; and, by that, increase efficiency.
Regions in parts of Scandinavia, Germany and Austria well integrated with new members have harvested the maximum benefits of enlargement. Yet a wider group of regions, often further off in terms of geography, saw some of the economic advantages as enlargements took hold. The single market’s expansion has driven these changes by fostering conditions under which businesses may expand, invest, and consequently acquire higher efficiency.
What Does this Tell us About Future EU Expansions?
The previous enlargement had been such a success for the 2004 round that there are really important lessons-to-be-learned for EU accession. Both candidate countries and established member states have much to gain from future enlargements-only if such enlargement takes place. The necessary reforms and hard work must follow.
But reforms and hard work will be welcome only under conditions of intense pressure on the candidate countries. The 2004 enlargement event required the seriously painful, harsh reforms cemented in the fabric of accession. Future candidates need to take even further effort to transform themselves, in a way that enables the good-conduct concept in governance with reduced corruption, while the rule of law is consolidated in business regulations. These reforms are aimed at pushing these countries’ systems and institutions closer to the standards of the EU.
In the case of existing EU member states, they must concentrate on deeper and wider integration within the Union. Removing the remaining barriers to trade and foreign investment within the EU and further advancing the Capital Markets Union activities are included. The reduction of business regulations stimulating greater economic coherence across the Union has a cumulative impact beyond the level of benefits from enlargement, which will consequently give a push to widening and deeper growth.
In the same vein, the newly joined with the not-so-newly joined member states must be very much concerned with reducing the income gap with the US through the advancement of necessary socio-economic reforms and united commitment to a broader vision of a more united and prosperous Europe.
2004 convinced the proponents that the EU expansion was nothing less than phenomenally successful. Expressed in earnest and deep reforms, political determination, and a shared understanding of the European project, 2004 is the guide for all future enlargements of the EU. It should constructively assess how potential future expansion will logically complement the mistakes, victories, and lessons of the past. Trying to construe the valuable experiences since 2004, the great lesson learned in any enlargement-the disputes of pre-accession reforms, the shedding of omni-present investments, and the ongoing integration-are more relevant than ever. An additional enlargement wave is set on its course with the right steps, giving a possible long-term impetus to some new states and enhancing the provisions for other old states as well with a more unified Europe in the offing.