Ireland: Irish Revenue updates Pillar Two guidance

The updated guidance outlines Pillar Two registration, filing, and top-up tax requirements for MNEs.

Irish Revenue published updated guidance on Pillar Two requirements on 14 August 2025, covering an overview of Pillar Two, registration procedures, payment and filing obligations, submission of the top-up tax information return and key dates and recent updates for taxpayers.

Pillar Two requires Multi-National Enterprises (MNEs) and large-scale domestic groups to pay a minimum of 15% tax on profits in each jurisdiction it operates. MNEs within scope are those with consolidated annual revenues of EUR 750m or more in two out of four preceding fiscal years.

Registration

The Pillar Two rules include an Income Inclusion Rule (IIR) and an Undertaxed Profits Rule (UTPR). The rules also allow jurisdictions to introduce a Qualified Domestic Top-up Tax (QDTT).

Entities located in Ireland must register with Revenue if they are subject to the:

• IIR top-up tax
• UTPR top-up tax or
• domestic top-up tax.

Entities must register within 12 months of the end of the first fiscal year they come within scope.

The deadline for in-scope entities to register with Revenue is 31 December 2025.

Pay and file

The Pillar Two rules include an Income Inclusion Rule (IIR) and an Undertaxed Profits Rule (UTPR). The rules also allow jurisdictions to introduce a Qualified Domestic Top-up Tax (QDTT).

IIR return and self-assessment

Relevant parent entities which are subject to the IIR top-up tax must file an IIR Return and self-assessment. This must be done within 15 months of the end of the fiscal year. This period is extended to 18 months for the first fiscal year that the entity is in scope. The amount of tax due must be paid at the same time the return is filed.

The pay and file deadline is 30 June 2026. Entities will be able to pay and file through the Revenue Online Service (ROS) in early 2026.

UTPR return and self-assessment

Relevant UTPR entities that are subject to the UTPR top-up tax must file a UTPR Return and self-assessment. This must be done within 15 months of the end of the fiscal year. This period is extended to 18 months for the first fiscal year that the entity is in scope. The amount of tax due must be paid at the same time the return is filed.

Simplified reporting arrangements in relation to the UTPR top-up tax may apply. All constituent entities of a Multi-National Enterprise (MNE) group that are subject to the UTPR top-up tax may elect to form a UTPR group.

The members of the UTPR group must appoint one member to be the UTPR group filer. The UTPR group filer must prepare and deliver a UTPR Return in respect of all members of the UTPR group for the fiscal year. The same pay and file arrangements apply as if the return was filed by a single entity.

The pay and file deadline is 30 June 2026. Entities will be able to pay and file through ROS in early 2026.

QDTT Return and self-assessment

Irish entities which are subject to a domestic top-up tax must file a QDTT Return and self-assessment. This must be done within 15 months of the end of the fiscal year. This period is extended to 18 months for the first fiscal year that the entity is in scope. The amount of tax due must be paid at the same time the return is filed.

Simplified reporting arrangements in relation to the domestic top-up tax may apply. A QDTT group may be formed by way of an election by:

• all constituent entities of an MNE group,
• all constituent entities of a large-scale domestic group

or

• the joint venture, plus all the joint venture affiliates of a joint venture.

The members of the QDTT group must appoint one member to be the QDTT group filer. The QDTT group filer must prepare and deliver a QDTT Return in respect of all members of the QDTT group for the fiscal year. The same pay and file arrangements apply as if the return was filed by a single entity.

The pay and file deadline is 30 June 2026. Entities will be able to pay and file through ROS in early 2026.

Top-up tax information return

The Pillar Two rules include an Income Inclusion Rule (IIR) and an Undertaxed Profits Rule (UTPR). The rules also allow jurisdictions to introduce a Qualified Domestic Top-up Tax (QDTT).

The Pillar Two rules provide that income of large groups is taxed at a minimum effective tax rate of 15% on a jurisdictional basis. The legislation in Part 4A of the Taxes Consolidation Act 1997 provides for three taxes:

1. IIR top-up tax.
2. UTPR top-up tax.
3. Domestic top-up tax.

A top-up tax information return must be filed with Revenue using the standardised OECD GloBE information return. The top-up tax information return must be filed with Revenue 15 months after the end of the fiscal year. This period is extended to 18 months for the first fiscal year that the entity is in scope.

The top-up tax information return will be available on the Revenue Online Service (ROS) in early 2026. For further information, please see Key dates and updates.

There are four ways which the top-up tax information return can be filed:

1. Each constituent entity of the Multi-National Enterprise (MNE) group located in Ireland files a top-up tax information return.
2. A designated local entity is appointed and files the return with Revenue on behalf of all the other entities located in Ireland.
3. The ultimate parent entity files the return with the tax authority in another jurisdiction. That other jurisdiction must have a qualifying competent authority agreement with Ireland which provides for the automatic exchange of top-up tax information returns. Please see the details below in relation to the requirement to file a notification of the filer.
4. A designated filing entity files with the tax authority in another jurisdiction. That jurisdiction must also have a qualifying competent authority agreement with Ireland which provides for the automatic exchange of top-up tax information returns. Please see the details below in relation to the requirement to file a notification of the filer.

Notification of filer

If the ultimate parent entity or designated filing entity files the top-up tax information return in another jurisdiction, an entity located in Ireland must inform Revenue.

The Irish entity must file a notification of the filer 15 months after the end of the fiscal year. This period is extended to 18 months for the first fiscal year that the entity is in scope.

Transitional simplified jurisdictional reporting

During a transitional period of five years, MNEs can elect to report under a simplified jurisdictional reporting framework. The transitional period is the period of fiscal years beginning on, or before, 31 December 2028 and ending on, or before, 30 June 2030.

Where certain conditions are met, MNE groups can report data on a jurisdictional basis, rather than on a constituent entity by constituent entity basis.

A Qualified Domestic Top-Up Tax (QDTT) group filer may file a domestic top-up tax return with Revenue on behalf of all Irish QDTT group members. In these cases, the MNE may elect to complete the top-up tax information return using the simplified jurisdictional reporting framework.

Completing the top-up tax information return, in line with this simplified jurisdictional reporting framework, can also be applied to top-up taxes arising in jurisdictions other than Ireland. This is on the basis that there is no charge to:

• an IIR top-up tax in Ireland

or

• a UTPR top-up tax in Ireland.

However, if there is a charge to either tax, there is no requirement for taxes to be allocated on a constituent entity by constituent entity basis.

Key dates and updates

Registration

The necessary IT developments required to allow registration of in-scope entities will be available on the Revenue Online Service (ROS) by mid-August 2025. This will enable entities to meet the 31 December 2025 registration deadline.

Pay and file
The necessary IT developments required to allow return filing and payment of associated liabilities will be available on ROS in early 2026. This will enable entities to meet the 30 June 2026 deadline for pay and file.

Top-up tax information return
The necessary IT developments required to allow the filing of the top-up tax information return will be available on ROS in early 2026. This will enable entities to meet the 30 June 2026 pay and file deadline.