Greece prescribes separate domestic top-up tax and IIR/UTPR returns

Greece has prescribed two separate Pillar Two self-assessment returns. AADE Decision A.1236/30 October 2026 covers domestic top-up tax; Decision A.1237/30 October 2026 covers the Income Inclusion Rule (IIR) and Undertaxed Profits Rule (UTPR). They were published in Official Gazette B6587 and B6588 respectively on 2 November 2026 and took effect on publication under article 7 of each decision.

The development supplies prescribed forms and submission procedures for liabilities already governed by Law 5100/2024. Article 49 already required electronic self-assessment and payment. 

Two returns

Under A.1236 article 2, the domestic return covers entities liable under article 12 of the law. Where a group has more than one Greek constituent entity, a designated local entity files. However, article 2(3) requires separate returns for each domestic member falling within the joint-venture and minority-owned categories specified in article 3(1)(a) and (b). 

A.1237 article 2 distinguishes the IIR and UTPR filing roles. For the IIR, it identifies the Greek-resident ultimate parent or designated filing entity in relation to obligations under articles 6–9. For the UTPR, it identifies the Greek constituent entity or, where there are several, the designated local entity. The form accommodates the relevant IIR and UTPR components; it is separate from the domestic-tax return.

Nil returns and electronic submission

Article 2 of both decisions requires filing even where no tax is payable. It also requires a separate return for each multinational group where an entity belongs to more than one group. Article 5 provides for electronic submission through myAADE, including submission by an authorised representative or accountant using the prescribed TAXISnet access, and for electronic amended returns.

GIR v self-assessment deadlines

Article 4 of each decision expresses the self-assessment deadline as the last working day of the month following the month in which the GloBE Information Return (GIR) deadline falls. Article 6 places payment on the last working day of the following month after the self-assessment deadline. 

The GIR and associated foreign-filing notification rules remain a separate compliance layer under article 48. Filing either local self-assessment form does not itself discharge those information obligations. The issued decisions should also be distinguished from the separate pending legislative proposal concerning foreign GIR filing.