Ireland Pillar Two Filing: Revenue's June 2026 Guidance and 30 June Deadline

Revenue published major Pillar Two guidance in May and June 2026, including new Tax and Duty Manuals on IIR, UTPR, and QDTT returns (eBrief 107/26) and on Top-up Tax Information Returns and Notifications of Filer (eBrief 106/26).

Groups with Irish constituent entities face ROS-only filing, XML validation for GloBE information returns, and a transitional 30 June 2026 pay-and-file deadline where the normal 15-month rule would have fallen earlier. This is primarily a large multinational compliance topic — but Irish subsidiaries of foreign groups and domestic scale-up companies above €750m consolidated revenue must act now.

Ireland implements the OECD Pillar Two model through Part 4A Taxes Consolidation Act 1997: Income Inclusion Rule (IIR) top-up tax, Undertaxed Profits Rule (UTPR) top-up tax, and Qualified Domestic Top-up Tax (QDTT).

Each in-scope entity may need an IIR, UTPR, or QDTT return and self-assessment on ROS, even when liability is nil. Nil returns are mandatory — absence of top-up tax does not remove the filing obligation.

Separately, constituent entities may file a Top-up Tax Information Return (TIR) — the GloBE Information Return — or submit a Notification of Filer (NoF) where the TIR is filed in another jurisdiction and exchanged under DAC9 or the GIR multilateral agreement.

Normally, GloBE returns and payments fall due within 15 months of the fiscal year-end — 18 months for the first year in scope. Revenue extended deadlines that would otherwise fall before 30 June 2026 to that date for initial IIR, UTPR, QDTT, TIR, and NoF obligations.

ROS now accepts IIR, UTPR, and QDTT returns and payments through the Manage Pillar Two portal. Specimen forms IIR1, UTPR1, and QDTT1 set out the data required.

TIR filings use XML schema validation with two validation levels confirmed via ROS inbox messages — allow time for technical rejection and resubmission before the deadline.

Where entities elect QDTT or UTPR groups, members must appoint a group filer who creates the group on ROS and submits a consolidated return. Non-filer members rely on the group return and do not file individually for that year.

Before filing, verify Pillar Two registration on ROS is complete and matches the entity's role — parent, constituent entity, or designated local entity for TIR purposes.

Late filing or payment attracts penalties, surcharges, and interest under Part 4A. Revenue's manuals cross-reference penalty sections in TDM 04A-01-01 — treat 30 June 2026 as hard for transitional cases.

Multinational groups with Irish operations, large-scale domestic groups, and standalone entities above the €750m revenue threshold are in scope. Most sole traders and small companies are not — but finance teams supporting Irish HQ groups should confirm no Irish constituent entity triggers UTPR.

Agents should read eBriefs 106/26 and 107/26 alongside TDM Part 04A-10-02 and 04A-10-03. Test XML TIR uploads in ROS before the final week of June.

FinnAccountings Compliance Agent tracks Revenue and OECD deadline changes for connected entities — contact us for enterprise Pillar Two calendar support or start a free trial for core Irish and UK tax compliance.