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. For further information, please see Key dates and updates. 

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. For further information, please see Key dates and updates. 

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. For further information, please see Key dates and updates.