By the first Pillar Two filing deadline in June 2026, Irish Revenue had received just over 40 Top-up Tax Information Returns. It had received around 700 Notifications of Filer and more than 600 domestic returns.
That ratio is the whole picture. Groups filed their information return centrally, as the framework intended — and then still owed Ireland a notification and a domestic return each. Roughly one group in fifteen filed the information return locally. Fourteen in fifteen filed something else.
It matches what we saw everywhere else. Across the same cycle my team delivered close to 500 Pillar Two filings in more than ten jurisdictions for over 160 groups. More than 150 of those were GIRs. The clear majority of the remainder were notifications and domestic returns — the filings groups had not planned for.
The OECD standardised the computation. It did not standardise the filing, and the gap between those two facts is where the first cycle went wrong.
The acronym problem is a real compliance risk
There is no jurisdiction that files a “QDMTT return”. The tax is called something different almost everywhere.
Jurisdiction | Domestic top-up tax | Information return | Where the GIR is filed elsewhere |
UK | Domestic Top-up Tax (DTT) | GIR | Overseas Return Notification (ORN) |
Ireland | Qualified Domestic Top-up Tax (QDTT) | Top-up Tax Information Return (TIR) | Notification of Filer (NoF) |
Netherlands | Local top-up tax return | BIA / GIR | Kennisgeving (notification) |
Germany | Minimum tax return | GIR (Mindeststeuer-Bericht) | Group head notification |
Australia | DMT, inside the CGDMTR | GIR | Foreign Lodgment Notification |
Belgium | QDMTT return | GIR | GIR notification |
This is not pedantry. A group searching its compliance tracker for “QDMTT” finds nothing in four of those six jurisdictions, and concludes there is no obligation. Ireland’s legislation refers to domestic top-up tax; Revenue’s guidance says QDTT; the OECD framework says qualifying domestic minimum top-up tax. Same obligation, three names, one of which appears on none of the local forms.
Build the tracker on obligations, not acronyms.
Get the 12-Point Domestic Top-Up Tax Filing Matrix
Six jurisdictions, six different names for the same tax. Get the full article as a PDF, including the 12-point matrix for tracking obligations instead of acronyms, and the deep dive into where Germany, Belgium and Ireland actually diverge.
Safe harbour reduces tax. It does not remove filings.
The QDMTT safe harbour, where the conditions are satisfied and the relevant election is made, can treat the group’s jurisdictional top-up tax as nil. That is a tax outcome. It is routinely read as a compliance outcome, and it is not.
Two separate questions, and they need separate answers:
- Do we owe domestic top-up tax here?
- Do we have a domestic top-up tax filing obligation here?
Italy requires its Pillar Two return even where no top-up tax is due for the year. Australia requires the combined return regardless of a nil position. Ireland’s 600 domestic returns were filed by groups that overwhelmingly owed nothing.
A nil answer to the first question almost never produces a nil answer to the second. In our engagements it was the single most common misconception, and the most expensive one, because it surfaced late.
The filing matrix
Before deadlines, before data collection, establish these twelve facts per jurisdiction. This is the artefact we now build every engagement around, and it is the one deliverable I would give any group entering cycle two.
Question | What to establish |
Is there a domestic top-up tax? | Yes / No |
What is it called locally? | The exact local name |
Is it OECD-qualified? | Status at the filing date, not at project start |
Is the safe harbour available? | Yes / No / conditions |
Is an information return required locally? | Yes / No / central filing route |
If filed centrally, is a notification owed? | Form, deadline, content |
Who is the filer? | UPE / local entity / designated entity |
Which deadline applies to each filing? | They rarely match |
Which authority receives it? | Not always the same one |
Which schema or format? | OECD XSD / local variant / portal form |
Which channel and credential? | Portal, API, agent access, certificate |
What evidences acceptance? | And where is it stored |
The last row is the one most often missing. A filing nobody can evidence six months later is a filing the group cannot defend.
Three jurisdictions where the divergence bites
Germany splits three obligations across two authorities. The group head notification is due within two months of the end of the tax period — against an 18-month first-year GIR window. The GIR goes to the Federal Central Tax Office in XML, either through the DIP mass-data interface, which requires technical setup, or the portal’s XML upload form. The minimum tax return goes to the competent state tax office instead. Portal access runs on an ELSTER certificate, a BZSt certificate or the federal user account, and simple credentials are not always sufficient. Late or incomplete GIR submission, where intentional or reckless, is an administrative offence carrying up to €30,000.
Belgium sets the QDMTT return at eleven months after year end — ahead of the GIR, not behind it. The authorities extended twice, first to June and then to September 2026, while the GIR deadline stayed at 30 June. Extensions are granted per return type, not per jurisdiction, and groups that read “Belgium has extended” as a blanket reprieve misread it.
Ireland requires registration within twelve months of the first in-scope fiscal year, with a €10,000 penalty for failure, and requires TIR registration even for entities that will never file one. Revenue’s own manual now includes guidance on resolving XML schema and validation errors — which tells you precisely where groups were getting stuck.
What filing readiness means now
The failures we saw in the first cycle were rarely computational. They were dependency failures: a local return waiting on a central calculation, a credential that took weeks to issue, a schema finalised shortly before its own deadline, a notification nobody had diarised because the tracker had searched for the wrong word.
That makes domestic top-up tax compliance a data transformation and submission problem as much as a tax one. The same group dataset has to produce different outputs, in different formats, through different channels, to different authorities, on dates that do not align.
The objective is not to arrive at the right number. It is to get the right information to the right authority, in the right format, through the right channel, by the right deadline — and to be able to prove afterwards that it arrived.
About the author
Saurabh Satija is Global Head of BEPS & Pillar Two and VP Sales, UK & Ireland at DataTracks, the HMRC-recognised regulatory reporting provider. He built DataTracks’ Pillar Two practice from zero and led its first live GloBE cycle: close to 500 filings, including more than 150 GIRs, for 160+ clients across 10+ jurisdictions. Based in London.
LinkedIn: linkedin.com/in/saurabhsatija
DataTracks is one of six HMRC-recognised Pillar Two software providers listed on GOV.UK, and filed across ten-plus jurisdictions in the first live GloBE cycle.
