Which candidate country will join the EU next

GPT-5.4

Vote: Montenegro

Montenegro is the strongest answer because it is the most advanced of these candidates in the EU accession process. It has been negotiating for years, opened all negotiating chapters, and is generally treated as the frontrunner among Western Balkan candidates. Several alternatives face bigger obstacles. Serbia has more serious political and foreign-policy complications, especially around Kosovo and alignment with EU positions. Albania and North Macedonia have progressed, but not as far overall, and North Macedonia has repeatedly been delayed by bilateral disputes. Bosnia and Herzegovina is institutionally less prepared. Ukraine and Moldova have strong political momentum because of geopolitics, but their accession path is still at an earlier and far more complex stage. Georgia has also lost momentum relative to the others. If the question is who is most likely to join next rather than who is strategically most important, Montenegro remains the clearest and most realistic pick.

Sonar Pro

Vote: Montenegro

Montenegro is the clear frontrunner to join the EU next. According to the European Commission's November 2025 enlargement report, Montenegro has already closed four negotiating chapters and is expected to finalize another six in 2026, positioning it to complete negotiations by the end of 2026[2]. The Commission describes Montenegro as 'a pioneer country for accession' with all 33 chapters opened and seven provisionally closed[5]. Albania, while also advanced with five of six negotiating chapters opened, is targeting 2027 for completion[2], making it the second most likely candidate but behind Montenegro[4]. The other options are significantly further behind. Ukraine and Moldova, despite recent progress, are not expected to join before 2028[2]. Georgia has experienced 'severe democratic backsliding' and is considered a candidate 'in name only'[3]. Serbia, Bosnia, and North Macedonia have not demonstrated comparable momentum in recent assessments[1].

Grok 4.1 Fast

Vote: Montenegro

Montenegro is the clear frontrunner among EU candidates. It opened accession negotiations in 2012, the first Western Balkan country to do so, and has provisionally closed two clusters (fundamentals and internal market) as of 2024, with more expected soon. Serbia (D) and North Macedonia (C) are progressing but lag behind; Serbia has Kosovo disputes, and Macedonia faces bilateral issues. Albania (B) and Bosnia (E) are earlier stage. Ukraine (F), Moldova (G), and Georgia (H) gained candidate status in 2022-2024 amid war, but reforms are nascent and accession could take a decade. EU officials and Montenegro target membership by 2028, making it the next likely joiner.

Kimi K2.5

Vote: Montenegro

Montenegro is objectively the furthest along in the EU accession process. It opened all 33 negotiating chapters in 2024 and has already provisionally closed eight of them—more than any other candidate in the Western Balkans. Unlike Serbia (blocked by Kosovo normalization issues), North Macedonia (blocked by Bulgaria over language disputes), or Bosnia (early stages), Montenegro faces no major bilateral blocking criteria. While political instability has caused delays, the technical alignment with EU law is the most advanced among all candidates. Ukraine, Moldova, and Georgia only gained candidate status in 2022-2023 and face years of reform ahead due to ongoing conflicts and institutional gaps. Albania started negotiations later than Montenegro and has more chapters remaining.

Claude Opus 4.6

Vote: Montenegro

Montenegro is the most advanced candidate country in EU accession negotiations. It opened accession talks in 2012 and has opened all 33 negotiating chapters, with three provisionally closed. No other candidate country is as far along in the formal accession process. While Ukraine and Moldova received candidate status in 2022 amid geopolitical urgency following Russia's invasion of Ukraine, they are far behind in the actual negotiation process and face enormous reform challenges. Ukraine's accession would also be extraordinarily complex given the ongoing war, its large agricultural sector, and its population size. Serbia, while also advanced in negotiations (having opened most chapters), faces significant political obstacles including its close relationship with Russia, the unresolved Kosovo issue, and democratic backsliding under President Vučić. These factors make Serbia's accession timeline more uncertain than Montenegro's. Albania and North Macedonia only formally opened accession negotiations in 2022, putting them years behind Montenegro. Bosnia and Herzegovina received candidate status in 2022 but hasn't started negotiations. Georgia's EU aspirations have been severely complicated by its government's authoritarian turn. Montenegro is small (about 620,000 people), making its integration relatively straightforward compared to larger candidates. It already uses the euro de facto and is a NATO member. While it still needs significant rule-of-law reforms, it remains the frontrunner by a considerable margin in the formal accession process.

Gemini 3.1 Pro

Vote: Montenegro

Montenegro is currently the absolute frontrunner in the European Union accession process. It has already opened all 33 of its screened negotiation chapters and provisionally closed three, placing it significantly ahead of all other candidate nations. Unlike many other candidates on the list, Montenegro does not have major unresolved territorial or bilateral disputes. Serbia is hindered by the ongoing Kosovo dispute, North Macedonia faces hurdles with Bulgaria, and Ukraine, Moldova, and Georgia face complex geopolitical and territorial challenges involving Russia. Furthermore, Montenegro's small population of roughly 600,000 means its eventual accession would be relatively easy for the EU to absorb economically and institutionally. The country already unilaterally uses the Euro as its currency and aligns 100% with the EU's common foreign and security policy, proving its readiness and commitment to EU integration.

Final Summary

The AI Roundtable reached a swift and unanimous consensus, identifying Montenegro as the clear frontrunner to become the next EU member state. While the geopolitical gravity of Ukraine and Moldova's recent candidacies was acknowledged, GPT-5.4 and Claude Opus 4.6 noted that technical alignment and the absence of major bilateral disputes give Montenegro an insurmountable lead in the formal accession process.

All 6 models agreed on "Montenegro" after discussion

Strongest Arguments

• Montenegro: Montenegro is the only candidate to have opened all 33 negotiating chapters and already unilaterally uses the Euro, making its integration economically and institutionally straightforward compared to larger, more politically complicated nations.