Pillar 2 - Registration and updates on implementation

The new Pillar 2 legislation which aims at ensuring a minimum effective corporate tax rate of 15% for groups which are within scope (broadly, groups with annual consolidated turnover in excess of €750 million) is moving to the next step of implementation in Ireland: the registration of entities in scope with Revenue.

Pillar 2 implementation

Launch of registration portal

Where the effective tax rate in a jurisdiction is below 15%, a top up tax may apply. The new Pillar 2 legislation applies and impacts groups for accounting years starting from 31 December 2023 onwards.

The Irish Revenue has now launched its Pillar 2 registration portal, marking a significant milestone in Ireland’s implementation of the OECD’s global minimum tax framework. In support to this, letters were issued to Irish Ultimate Parent Entities (UPEs) and Constituent Entities (CEs) of Multinational Enterprise (MNE) groups advising of the new facilities and obligations.

Irish entities which are within scope of Pillar 2 rules must register within 12 months of the end of the first fiscal year in which they come within scope of Pillar 2. For example, where the accounting year end of a group is 31 December, the registration deadline is 31 December 2025.

While certain groups and Irish entities may still be unsure on the type of Pillar 2 registration required in Ireland, it is essential for entities which are within scope to register on or before the due date which applies to them. As often with significant changes and milestones, while we all become familiar with the new legislation and associated facilities, we understand that Revenue will allow for minor adjustments where the initial registration is completed on time.

Next milestone in 2026

For groups with a 31 December year end, once the registration process is completed, the next milestone will come in June 2026, with the first filing, and, where applicable, the first payment.

At the time of writing these lines we are awaiting further guidance from the Irish Revenue in terms of the format and system which will be used to gather the relevant returns. Other tax authorities have implemented and are using different approaches and systems. We are now waiting for the Irish Revenue to announce further details on this in early 2026, so that we can advise groups with Pillar 2 filings due in Ireland accordingly.

Simplification measures

The Pillar 2 rules bring new challenges, with additional filings supporting by computation and tracking done at group and each jurisdiction level rather than entity level.

Two separate agreements (DAC9 and the GIR-MCAA) aim at simplifying the filing process and reducing the administrative burden for groups which are within scope of Pillar 2 by enhancing the automatic exchange of information included in the GloBE Return (“GIR”). 

DAC9 applies to EU Members States, while the GIR-MCAA has been signed by jurisdictions in and outside the EU. In practice, where a MNE group with Irish entities files its GloBE Return in either an EU Member States (covered by DAC9) or in a jurisdiction which is a signatory of the GIR-MCAA (such as the UK, Switzerland or Japan), there will be no requirement to file a GloBE Return in Ireland as well.

The full list of signatories of the GIR-MCAA is available here.

If you have any questions in relation to the above, or if you would like to discuss this topic further, please contact a member of the Mazars corporate tax team below: