How many of the negotiating chapters required to join the EU will Montenegro have closed at the end of 2026?

TL;DR

My forecast is 27 provisionally closed chapters at the end of 2026, with an 11% chance Montenegro reaches all 33.

Context

Montenegro has opened all 33 EU accession negotiating chapters, and the official current count is 14 provisionally closed chapters after the 17 March 2026 closure of Chapter 21, Trans-European networks; the Commission repeated the same 14-chapter count on 20 May 2026 (Council, 17 March 2026; Commission, 20 May 2026). That leaves 19 chapters to close before 23:59 CET on 31 December 2026.

The political target is real. Montenegro’s government has a 2026 roadmap for closing all chapters, and the Council has started an ad hoc working party to draft Montenegro’s accession treaty (Montenegro Ministry of European Affairs, 31 January 2026; Council notice, 8 May 2026). But chapter closure is still intergovernmental, the Council generally works by unanimity on enlargement, and an accession treaty is signed only after negotiations are completed (Council, how enlargement works).

Evidence

The historical series is a count of chapters provisionally closed at EU-Montenegro accession conferences. Coverage window: 18 December 2012 through 20 May 2026. Sample size: eight closure events, covering 14 chapters. Vintage: official EU pages and documents available on 24 May 2026; the Commission’s 20 May 2026 news item is the freshest official count I found (Commission, 20 May 2026).

The base rate changed after the June 2024 rule-of-law milestone. Before December 2024, Montenegro had closed only three chapters in roughly twelve years; after the EU confirmed in June 2024 that Montenegro had overall met the interim benchmarks for Chapters 23 and 24, it closed 11 chapters from 16 December 2024 through 17 March 2026 (Council, 16 Dec 2024; Council, 17 March 2026). That is a real acceleration. It is still much slower than the 19 additional closures needed by 31 December 2026.

The near-term pipeline is visible but narrow. Council working-party agendas show draft common positions for Chapter 2, freedom of movement for workers, and Chapter 28, consumer and health protection, on 9 April, 20 April, and 12 May 2026; the 19 May 2026 agenda still had Chapter 28 and a rule-of-law non-paper on Chapters 23 and 24 under discussion (Council agenda, 9 Apr 2026; Council agenda, 20 Apr 2026; Council agenda, 12 May 2026; Council agenda, 19 May 2026). Montenegro’s chief negotiator also pointed to Chapters 1, 16 and 29 as near-term closure targets, while the Commission co-chair said efforts needed to intensify especially on Chapters 1 and 16 (Government of Montenegro, 28 Apr 2026).

The positive case rests on administrative mobilisation and EU political lock-in. Montenegro’s 2026-2027 accession programme covers 581 acts, with 495 planned for 2026, and says obligations tied to chapter closure are concentrated in the first two quarters of 2026 (Montenegro Ministry of European Affairs, 31 January 2026). The accession-treaty working party began on 13 May 2026, and Agence Europe reported that Commissioner Marta Kos said Montenegro could conclude the technical part of negotiations by the end of 2026 or the beginning of 2027 if reforms continue (Council notice, 8 May 2026; Agence Europe, 14 May 2026). I read this as strong support for a high-20s outcome, not as proof of 33 by the deadline.

The negative case is the composition of the remaining chapters. The Commission’s 2025 Montenegro Report was published on 4 November 2025 and covers 1 September 2024 to 1 September 2025; it says Montenegro’s institutions remain fragile and that the legislative alignment process slowed in early 2025 on Chapters 23 and 24 (Commission Montenegro Report 2025). Montenegro itself said in February 2026 that the EU closing position for Chapter 23 requires constitutional amendments on the Judicial and Prosecutorial Councils (Government of Montenegro, 19 Feb 2026). Chapter 27 is also hard: the Commission rated Montenegro at only “some level of preparation” and said only 109 of 281 planned activities, or 38%, had been implemented in the Chapter 27 action plan by June 2025 (Commission Montenegro Report 2025). Chapter 12 still lacked framework legislation for official food controls and sufficient administrative capacity in the same report (Commission Montenegro Report 2025).

There is also a member-state veto risk. Croatia blocked the closure of Chapter 31 in December 2024 even though the chapter is technically about foreign, security and defence policy, an area where Montenegro has generally aligned closely with the EU (HRT, 16 Dec 2024; Commission Montenegro Report 2025). Reporting in April 2026 said Montenegro and Croatia were seeking renewed talks, but still listed Morinj, Kotor pool naming, the Jadran ship and Prevlaka as open issues (CE Report, 30 Apr 2026).

The Croatia analogue shows that a final sprint can happen, but it also shows why 33 is a stretch. Croatia had 31 of 35 chapters provisionally closed on 6 June 2011, then closed the final four on 30 June 2011, including competition, judiciary and budgetary provisions (Council, 6 Jun 2011; Croatian MFA, 30 Jun 2011). Montenegro is earlier in the endgame: it has 14 of 33 closed and needs 19 more by year-end.

My distribution starts from 14 and treats remaining closures as correlated batches rather than independent chapter coin flips. I put 8% on a stall or adverse path ending at 13-18, including a tiny reopening/dispute tail; 18% on 19-23; 34% on 24-28; 29% on 29-32; and 11% on all 33. The resulting mean is 26.5 chapters, the median is 27, the probability of at least 30 chapters is 33.5%, and the probability of all 33 is 11%.

What's non-obvious

The obvious bullish read is that treaty drafting means the chapters will close. It does not. The Council working party is a strong signal that the EU is preparing for accession, but Agence Europe reported that treaty drafting was unlikely to be completed by year-end and that Kos framed the technical close as possible by the end of 2026 or the beginning of 2027 (Agence Europe, 14 May 2026). A one- or two-month slip would barely matter for a 2028 membership story. It matters fully for this question.

The obvious bearish read is that 14 of 33 is too far away. That also misses the process change after the 2024 rule-of-law milestone. Since closures resumed, Montenegro has closed large batches, including five chapters in one December 2025 conference (Council, 16 Dec 2025). The right forecast is lumpy: many chapters can close late in the year, while one hard rule-of-law, environment, budget or Croatia-sensitive chapter can still keep the total below 33.

Limitations

The most important evidence is not public. Draft common positions, closing-benchmark assessments and member-state reservations are often handled in Council working papers that are not fully accessible. The public Council agendas show a pipeline for Chapters 2 and 28, and some work on Chapters 23 and 24, but not a full chapter-by-chapter calendar for the remaining 19 chapters (Council agenda, 19 May 2026).

The best full Commission chapter assessment is the 2025 report, which was published on 4 November 2025 and covers developments only through 1 September 2025 (Commission Montenegro Report 2025). Montenegro says it has done substantial work in early 2026, and some of that is visible in laws and Council agendas, but a later comprehensive Commission report was not yet available by 24 May 2026.

The final risk is political timing. An accession conference on 20 December 2026 versus 20 January 2027 could change this resolution by several chapters even if the underlying reform progress is the same. That calendar risk is why I put substantial mass at 29-32 and only 11% at exactly 33.