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

TL;DR

My central estimate is 27 chapters provisionally closed at year-end; 28 is the most likely exact count, starting from the Council's verified baseline of 18. Montenegro is at 18 of 33, and public Council records show draft EU common positions for six of the 15 open chapters, making a sizable technical package the base case (chapters 12, 18 and 19, chapter 1, chapter 17, chapter 15). The model's central 80% interval is 23–31, with 21% on 30 or more and 3.1% on all 33; these are model outputs from the documented Council pipeline and Croatian constraints, not source estimates.

Context

The client's March count is stale. The latest formal Accession Conference was on 14 July 2026, when chapters 8 and 29 closed and the cumulative total reached 18; 15 chapters remain open: 1, 9, 12, 14, 15, 16, 17, 18, 19, 22, 23, 24, 27, 31 and 33.

The political calendar still offers regular General Affairs Council windows on 13 October, 19 November and 15 December 2026, but a GAC is not automatically an Accession Conference. Ireland has publicly set the goal of completing Montenegro's negotiations during its presidency, while the Council had not posted a later Montenegro conference by the cutoff (Irish presidency address; Council calendar).

Evidence

The historical record is lumpy. Montenegro's full provisional-closure history is:

The acceleration is real: only three chapters closed by mid-2017, then 15 closed from December 2024 through July 2026. The five-chapter conference in December 2025 proves that large packages are operationally possible, but clearing all 15 remaining chapters in one quarter would exceed Montenegro's own precedent by a wide margin (Council chronology).

Croatia is the best completed endgame analogue. It had 28 of 35 chapters closed on 22 December 2010, reached 30 on 19 April 2011, 31 on 6 June 2011, and closed the final four on 30 June 2011. That is seven closures in its final 72 days, including hard chapters, but Montenegro needs 15 in roughly the same order of time.

The strongest current evidence is the Council pipeline. Draft EU common positions are public for chapters 1, 12, 15, 17, 18 and 19; chapters 18 and 19 were described by Montenegro's minister as awaiting Dutch handling rather than fresh technical work (minister's statement). Chapter 22 has a newly adopted national final position covering six closing benchmarks, and the Commission has already sent the financial package that precedes a common position for chapter 33 (chapter 22; chapter 33). These signals support a center above 24, while candidate-government claims remain weaker than Commission approval and unanimous EU consent.

The main downside is correlated political risk. Croatia's government says resolution of bilateral disputes is necessary for completing the talks, naming wartime detainee compensation, 14 missing persons, war-crimes cases, property claims, the maritime boundary and the training ship Jadran (Croatian Foreign Ministry). Reporting says Croatia was withholding clearance for chapters 14, 23, 24 and 31, though the official Croatian statement does not itself name those four chapters (Euronews). Chapters 23 and 24 also had unfinished constitutional and appointment work at the cutoff, while chapter 27 still required an operational Natura 2000 network, waste plans and stronger implementation capacity (rule-of-law steps; environment).

I modeled the 15 open chapters under five shared scenarios: procedural stall at 9%, a limited technical package at 30%, a strong technical sprint with the Croatian block largely intact at 40%, a partial bilateral deal at 17%, and a full endgame at 4%. Within each scenario, chapters are Bernoulli events; mixing the scenarios creates the needed positive correlation across chapters. I also reserve 0.02% for one previously closed chapter being reopened. The resulting mean is 27.03, the median is 27, the mode is 28, and the central 80% interval is 23–31. The weights are my judgment, anchored to the formal Council pipeline, the Irish presidency objective and the Croatian veto risk.

What's non-obvious

The count has natural shelves. The six public draft common positions create a path from 18 to 24 without solving the hardest political files. Adding chapters 22 and 33 points toward 26. If the reported four-chapter Croatian block persists while every other open chapter closes, the practical ceiling is 29. That structure is why the distribution peaks in the high 20s rather than drifting smoothly toward either 18 or 33 (Council pipeline; Croatia reporting).

Treaty drafting and the financial package are strong endgame signals, but neither closes a chapter. The September conference slipping over member-state procedures shows that technically advanced files can miss a window, while the absence of a posted future IGC is only an uncertainty, not evidence that none will occur (treaty working party; financial package).

Uncertainties

• The full texts of several Council draft common positions are restricted. Their existence proves advancement, not final approval by all 27 governments (Council register).
• Montenegro said nine negotiating positions had been sent and six more would follow by the end of September, but it did not identify the full nine-plus-six mapping in that announcement (government statement).
• The Dutch issue around chapters 18 and 19 is described mainly by Montenegrin officials; I did not find a public Dutch document granting or refusing final clearance for those two chapters (reported status).
• Croatia's official statement confirms broad bilateral conditions, while the exact four-chapter block comes from diplomatic reporting. A bilateral compromise could therefore move several outcomes at once, and failure could leave the same group open (official position; reported chapters).