Tax Alert: Top-up Tax (Pillar 2) in Spain

On 29 October 2025, Order HAC/1198/2025 of 21 October was published in the Official State Gazette, approving form 240 "Communication of the constituent entity filing the Top-up Tax information return", Form 241 "Top-up Tax Information Return", and Form 242 "Self-Assessment of the Top-Up Tax" and establishing the conditions and procedure for their submission.

The purpose of this Order is to approve the corresponding declaration forms, as well as the manner, deadline and place of submission, and other relevant information for compliance with tax and formal obligations relating to the Top-up Tax in Spain.

Despite the lack of consensus among several key jurisdictions (including the United States) and the uncertainties it generates, the bureaucracy of Pillar Two continues unabated. It should be recalled that, in Spain, for groups whose Fiscal Year coincides with the calendar year, the Top-up Tax already came into force in 2024 and that the related compliance obligations will need to be fulfilled through these filing forms between April and July 2026.

Below, we will analyze the main elements of each of these forms.

Form 240 - Communication of the entity filing the Top-up Tax Information Return

Entities required to file Form 240

Those constituent entities (CE) located in Spain that are exempt from the obligation to file the Information Return, for the purpose of reporting which entity will comply with this obligation.

A single communication including all constituent entities based in Spain may be submitted.

Contents of Form 240

This communication must include the information specified in Annex I of the Order, which essentially includes:

-        Identification of the CE making the communication, as well as any others covered by the same declaration.

-        Identification of the ultimate parent company (UPE) of the group and of the CE filing the Information return (GloBE Information Return, or GIR).

-        The tax period to which the communication refers and, if the GIR has already been filed, the date of filing and the reference number thereof.

-        Identification of the taxpayer's substitute, where applicable.

Deadline for filing form 240

-        Tax periods ending before 31 March 2025: within two months prior to 30 June 2026 (between 30 April and 30 June 2026).

-        Subsequent financial years: Before the last three months prior to the deadline for filing the Information return, which we will detail in the following section.

For taxpayers whose financial year coincides with the calendar year, the form must be submitted before 31 December of the year following the accounting year-end.

Form 241 – Top-up Tax Information Return

Entities required to file Form 241

In principle, all constituent entities based in Spain are required to file this form. However, if the UPE or another entity (in Spain or abroad) has been designated to file the return, the other entities will not be required to file it.

Entities that have been exempted from filing the return shall be subject to the provisions of the previous section in relation to Form 240.

Contents of Form 241

This is detailed in Annex II of the Order and includes all the information relating to the corporate structure of the group, details of the main figures and data required by jurisdiction for the potential application of the various safe harbors, as well as the calculations for the application of the Top-up Tax and its allocation in the various jurisdictions (where applicable).

Deadline for filing Form 241

-        Tax periods ending before 31 March 2025: within two months prior to 30 June 2026 (between 30 April and 30 June 2026).

-        Subsequent years: until the last day of the fifteenth month following the last day of the tax period.

For taxpayers whose financial year coincides with the calendar year, the form must be submitted before 31 March of the second year following the end of the accounting period.

Form 242 - Top-up Tax Self-assessment (QDMTT form)

Entities required to file Form 242

Entities located in Spain that qualify as taxpayers, or as substitutes for the taxpayer, are required to file the return

Contents of Form 242

Form 242 shall include the following information:

-        Identification of the tax period.

-        Identification of the designated entity which is filing the Top-up Tax self-assessment.

-        If the return is filed by a substitute for the taxpayer, identification of the taxpayer. In this case, the taxpayer's substitute, in addition to its own self-assessment, must file as many self-assessments as there are taxpayers they are substituting for.

-        Identification of the multinational or large national group to which the taxpayer belongs.

-        Identification of the UPE, indicating whether it is an excluded entity or not, and the status of approval and validity of the different modalities of TuT in its jurisdiction.

-        Identification of the information return filed (GIR) where the calculations necessary to self-assess the TuT are included.

-        In the case of self-assessment of the primary TuT (IIR rule), it must be indicated whether the taxpayer is an UPE, an intermediate parent entity (IPE) or a partially owned parent entity (POPE).

Under the current wording of the regulations, each Spanish entity that is a taxpayer of the TuT must file its self-assessment, even if the tax liability is zero. This circumstance does not seem to fit in well with the long-awaited and announced reduction in administrative burdens. We must therefore remain alert to the possibility of administrative modifications/ clarifications on this regard.

Deadline for filing form 242

-        First financial year: within 25 calendar days following the eighteenth month after the end of the transitional tax period.

For taxpayers whose tax year coincides with the calendar year, the form must be submitted before 25 July 2026.

-        Subsequent financial years: within 25 calendar days of the fifteenth month following the end of the tax period.

For taxpayers whose financial year coincides with the calendar year, the return must be filed by 25 April of the second year following the accounting year-end to which the return relates.