Belgium Pillar Two Filing Guide 2026
Belgium Pillar Two Filing Guide 2026: Deadlines, Schemas and What Goes Wrong
TL;DR- Belgium’s first Pillar Two compliance cycle stacks four separate filings onto 30 September 2026: GIR Notification, QDMTT return, IIR return, and (via administrative tolerance) the GIR itself.
- Belgium runs three of its own XSD schemas on top of the OECD’s GIR schema, for the GIR Notification, QDMTT return, and IIR return. A file that passes OECD validation hasn’t been tested against any of them.
- Belgium sets its “General Representative” by default: whichever entity files first is deemed to hold the role, unless one is formally designated in advance.
- Registration must be complete before MyMinfin will accept any filing.
- The calendar doesn’t reset after September: FY2025 QDMTT returns are due 30 November 2026, and a UTPR return follows once the BTA’s draft template is finalised.
The Belgium Pillar Two deadline: what is due on 30 September 2026
Belgium implemented the EU Minimum Tax Directive through the Law of 19 December 2023. For the first compliance cycle, the Belgian tax authorities (BTA) have aligned four obligations on a single date:| Filing | Format | Who files | Statutory deadline | First-cycle deadline |
| GIR (if Belgium is the filing jurisdiction) | OECD GIR XML schema + OECD business rules; no Belgian variant | UPE or designated filing entity | 18 months after FY end | 30 June 2026; ITAA has communicated no penalties if filed by 30 Sept 2026 (administrative tolerance, formal confirmation expected) |
| GIR Notification | Belgian form + Belgian XSD (published early July 2026) | Each Belgian constituent entity, unless one is designated | Aligned with GIR | 30 Sept 2026, covers assessment years 2024 and 2025 |
| QDMTT return | Belgian template + Belgian XSD; dedicated BTA FAQ | General Representative on behalf of Belgian entities | 11 months after FY end | 30 Sept 2026 (extended); FY2025 returns due 30 Nov 2026 |
| IIR return | Belgian template + Belgian XSD | Each IIR-liable taxpayer | 18 months (FY starting on/before 31 Dec 2024), then 15 months | 30 Sept 2026 (extended) |
| UTPR return | Draft template only (consultation opened 16 June 2026) | General Representative | From FY2025 | Not yet due, template not final |
Get the Belgium Pillar Two Deadline Checklist
A one-page checklist mapping every Belgian filing due 30 September 2026, so nothing slips through with the calendar stacking against you.
Why Belgian Pillar Two filing is harder than the OECD GIR suggests
The OECD designed the GloBE Information Return so that a group prepares one XML file, once, and files it centrally. Belgium sits on top of that with its own layer. Eight differences matter in practice.
1
Three Belgian schemas alongside the OECD schema
Top-up Tax) return, IIR (Income Inclusion Rule) return, and GIR Notification are Belgian-defined forms with their own XSDs. A file that passes the OECD business rules has not been tested against any of them. Validation happens twice, against two different rule sets, and an inconsistency in an entity identifier, jurisdiction code, fiscal period or amount format between the two can block a filing even when the underlying computation is correct.
2
No XML conversion tool from the BTA
The Belgian tax authorities are not expected to release a conversion tool. Generating schema-valid XML for each Belgian filing is entirely the taxpayer's, or its platform's, responsibility.
3
Entity-level, not group-level, obligations
The GIR is a group return. In Belgium, the GIR Notification is due from each Belgian constituent entity unless one is designated, and each IIR-liable taxpayer files its own IIR return. A group with several Belgian entities can have more Belgian filings than it has jurisdictions.
4
The General Representative is set by default
The General Representative is the BTA's primary contact and carries QDMTT and UTPR (Undertaxed Profits Rule) compliance responsibility for the Belgian entities. Under the BTA FAQ, the entity that files the first QDMTT return, UTPR return or GIR in Belgium is deemed to be the General Representative unless one has been formally designated via MyMinfin. Whichever entity submits first becomes the group's Belgian point of contact, whether or not that was the plan.
5
Registration comes first
In-scope groups must be registered for Pillar Two in Belgium before MyMinfin will accept filings. Unregistered groups cannot comply by the deadline and face penalties.
6
Two assessment years in one notification cycle
The first GIR Notification cycle covers assessment years 2024 and 2025 together, both due 30 September 2026.
7
Deadline stacking
30 September is also the Belgian corporate income tax return and local transfer pricing deadline. Expect heavy MyMinfin load and limited BTA response time in the final week. A validation error found on 28 September leaves almost no room to correct.
8
The calendar does not reset
FY2025 QDMTT returns are due 30 November 2026, two months after the first-cycle deadline, with the first UTPR return following once the template is final. Whatever process is used in September gets re-run almost immediately.
What the June 2026 GIR cycle taught everyone
The first GIR filing season made one thing clear: a return can be right under the GloBE rules and still be unfileable. Across jurisdictions, it was validation against the technical schema, not the underlying GloBE calculation, that tripped up many groups. Schema validation stopped being plumbing and became, in effect, a second rulebook, one that varies by jurisdiction. Belgium’s stack of local XSDs is exactly where that lesson applies.
Get the Full Belgium vs OECD GIR Reference Guide
The complete two-page reference: every deadline, every schema difference, and the four-week checklist, sent straight to your inbox.
Belgium Pillar Two checklist: the next four weeks
- Confirm Belgian Pillar Two registration is complete for every in-scope Belgian entity.
- Decide, rather than default into, which entity should be the General Representative, and whether to lodge a formal designation.
- Confirm who files the GIR Notification and that both AY2024 and AY2025 are covered.
- Generate the QDMTT, IIR and Notification XML files and validate each against the relevant Belgian XSD, not only the OECD GIR schema.
- Reconcile entity identifiers, fiscal periods and jurisdiction data across the GIR and the Belgian filings so the two rule sets do not contradict each other.
- If the GIR is filed in Belgium, run it through the MyMinfin simulation environment now, not in the final week.
- Target internal sign-off by mid-September to keep a correction window before the CIT/TP deadline stacking.
- Carry the same file structure forward for the FY2025 QDMTT return due 30 November 2026.
Frequently Asked Questions
What is the Belgium Pillar Two deadline for 2026?
30 September 2026 for the GIR Notification, QDMTT return and IIR return (extended from their statutory dates). The GIR itself was due 30 June 2026, with an administrative tolerance to 30 September communicated by ITAA. FY2025 QDMTT returns are due 30 November 2026.
Who files the GIR notification in Belgium?
Each Belgian constituent entity must notify the BTA annually of the GIR filing entity, unless a single Belgian entity has been designated for the group. The form and its XSD were published in July 2026 and are submitted via MyMinfin.
What is a General Representative under Belgian Pillar Two?
The Belgian entity that acts as the BTA’s primary contact and handles QDMTT and UTPR obligations on behalf of the Belgian group entities. If none is formally designated, the entity that files first is deemed to hold the role.
Does Belgium have its own QDMTT return format?
Yes. The Belgian QDMTT return has its own template and XSD schema, published with a dedicated BTA FAQ, and is separate from the OECD GIR schema.
Can I test my Belgian Pillar Two files before filing?
MyMinfin offers a simulation environment for the GIR. For the QDMTT, IIR and Notification files, validation against the Belgian XSDs needs to happen in your own tooling or platform before submission.
Test before MyMinfin does
Oxbow, DataTracks’ HMRC-recognised Pillar Two platform, has delivered 450+ Pillar Two reports across 32 jurisdictions. For Belgium it generates the GIR, QDMTT return, IIR return and GIR Notification from a single data set and validates each against the applicable Belgian XSD before submission, so a failure shows on screen, not on MyMinfin.
Book a free 30-minute validation session. Bring your draft data, we run it through the Belgian rule set live, and you leave knowing what passes, what fails, and why.
