Position dated 3 October 2026. Status: Adopted, not yet in force. Instrument: Pravilnik o bližem načinu izvještavanja o dopunskom porezu, obliku i sadržini prijave sa informacijama o dopunskom porezu (Rulebook on top-up tax reporting and the form of the top-up tax information return), Official Gazette of Montenegro 143/2026, published 1 October 2026, registration number 2476. It enters into force on 9 October 2026.
When Montenegro's global minimum tax act was published in March, the filing duty was already in it, but the form was not. Article 28(9) of the Zakon o globalnom minimalnom porezu na dobit pravnih lica (Gazette 33/2026) left the form, the supporting data and the filing procedure to the Ministry of Finance. Our earlier note on the 15% floor and what it costs ended by telling groups to confirm the forms with the tax authority. The Ministry has now answered that question in a 35-page rulebook, five pages of rules and thirty of form.
What the rulebook requires
Article 3(1) makes every constituent entity of an in-scope group a filer. Article 3(2) then removes the duty if the ultimate parent, or an entity it designated, has filed centrally in a jurisdiction that has a valid qualifying competent authority agreement with Montenegro for that fiscal year. That is the same exemption already written in Article 28(3) of the Act. What the rulebook adds is mostly procedure.
| Rule | Article | What it means in practice |
|---|---|---|
| Who files | Rulebook Art. 3(1); Act Art. 28(2) | Each Montenegrin constituent entity, or a designated local entity |
| Central filing exemption | Rulebook Art. 3(2); Act Art. 28(3) | Only where the filing jurisdiction has a valid agreement with Montenegro for that year |
| Notice of the filer | Rulebook Art. 4(1)–(3) | Identity and jurisdiction of the filing entity, at least 30 days before the return deadline; renews automatically |
| Fallback | Rulebook Art. 4(4), Art. 5 | If the named entity does not file, the Montenegrin entity must; the tax authority will request local filing |
| Format | Rulebook Art. 10 | Electronic, XML, on Form PIDP annexed to the rulebook |
| Deadline | Act Art. 28(6) | 18 months after the last day of the fiscal year |
| Exchange by the authority | Rulebook Art. 11(3) | Three months after the filing deadline; six months for the first year |
The notice under Article 4 is the item most likely to be missed. It is filed for the first reporting year, and Article 4(2) says it then "automatically extends each following year" until the group names a new filer. Where Montenegro has only one constituent entity, Article 4(3) requires the notice in the first year only.
Article 8(2) covers a different case: a Montenegrin subsidiary whose ultimate parent sits in a third country applying equivalent rules. The local entity then files a return limited to listed items, including the information needed for the domestic top-up tax. Article 9 lets the tax authority ask for more.
What the rulebook does not settle
It does not say which jurisdictions count. Article 2(7) defines them as those with an agreement on automatic exchange of the return, and says the list is published on the tax authority's website. We searched for that list on 3 October 2026 and did not find it. Until it is published, a group cannot point to it to rely on the central filing exemption, and our cautious reading is to plan for the notice and, if needed, local filing.
It is also not the return for paying the tax. Article 30 of the Act imposes a separate domestic top-up tax return and payment. Gazette 143/2026 contains no rulebook for that return; we checked the issue's contents and found only this one on the information return.
Nor does the rulebook fix the first year. The Act has no separate application clause, as our earlier note explained. If 2026 is the first fiscal year, a calendar-year group's first information return falls due on 30 June 2028, and the Article 4 notice by 31 May 2028. That is our reading, not a date written in either text.
Our reading
For a group above the €750 million threshold with a Montenegrin subsidiary, the work this month is small and specific. Decide who files: the parent centrally, or a Montenegrin entity. If there are two or more Montenegrin entities, Article 28(7) of the Act already requires one of them to be designated as responsible. Then put the 30-day notice in the compliance calendar, because it falls a month before a deadline that most teams will track from the parent's side. The XML requirement in Article 10 matters to whoever builds the return. A PDF will not satisfy it.
What did not change
The 18-month deadline, the €750 million threshold and the domestic-only design of the Act stay as they were in Gazette 33/2026. The rulebook does not create a top-up tax, change the rate or reach entities outside Montenegro. Penalties remain in Articles 33 and 34 of the Act; the rulebook adds none. The same gazette issue also carried a rulebook on applying the new VAT act, and that one applies only from the day Montenegro joins the EU (its Article 148). The Pillar Two rulebook has no such clause.
How to verify
The rulebook is in the gazette register at sluzbenilist.me/propisi/398696. The legal basis is on page 1, Articles 3 and 4 on page 2, Article 10 on page 4, and Article 13 (entry into force on the eighth day) on page 5. Form PIDP starts on page 6. The Act itself is at sluzbenilist.me/propisi/391203; Article 28 is on pages 29 and 30. Our related note on Montenegro's anti-avoidance rulebooks shows the reporting side of the same package. If you want help setting up the filer notice and the local entity structure, see our international tax work and company formation pages. We follow this file under Legal Updates.