Spain has taken a significant step toward aligning with international tax standards through the implementation of Pillar 2 of the Organisation for Economic Co-operation and Development (OECD), which introduces a minimum 15% Top-up Tax for large multinational and domestic groups.
The measure has been incorporated through Law 7/2024 of 20 December, transposing Directive (EU) 2022/2523, with the aim of preventing base erosion and profit shifting to low-tax jurisdictions.
What is the Pillar 2 Top-up Tax?
The Pillar 2 Top-up Tax ensures that business groups with an international presence are subject to a minimum effective tax rate of 15%, regardless of where they operate.
This mechanism forms part of the global agreement promoted by the OECD to combat aggressive tax planning and ensure a more equitable international tax framework.
Who must comply with Pillar 2 in Spain?
This new tax framework applies to:
- Multinational groups
- Large domestic groups.
Provided that they have consolidated revenues of at least €750 million in at least two of the previous four fiscal years.
The legislation is complemented by Royal Decree 252/2025, which develops the technical and operational aspects required for its implementation.
Top-up Tax reporting forms
The Spanish Tax Agency (AEAT) has established three key forms for the administration of Pillar 2 in Spain:
Form 240 – Group notification
This form identifies the group entity responsible for filing in Spain.
It allows:
- Centralised group communication
- Unified management of the Spanish entities within the group.
Form 241 – Informational return (GIR)
Also known as the GloBE Information Return, this is the main tax reporting form under Pillar 2.
It includes information such as:
- The structure of the multinational group
- The effective tax rate
- The allocation of the Top-up Tax.
The form must be submitted in XML format in accordance with OECD and EU standards.
Form 242 – Tax self-assessment
This form is used to calculate and settle the Top-up Tax.
- Filing is mandatory even if the tax liability is zero or negative
- It determines the final amount payable.
Implementation timeline and key dates for 2026
The Spanish Tax Agency has established a transitional regime for the first implementation of Pillar 2:
Filing of Forms 240 and 241
- For tax periods ending before 31 March 2025
- Filing period: 30 April to 30 June 2026.
Filing of Form 242
- Initial self-assessment period
- Filing deadline: 1 to 27 July 2026.
Technical requirements and electronic filing
Compliance with Pillar 2 requires fully electronic submission.
Form 241:
- Must be submitted in standardised OECD/EU XML format
- Is transmitted through Tax Agency Web Services
- Requires a valid electronic certificate.
In addition, the Tax Agency has enabled a testing environment until April 2026, allowing groups to:
- Validate their submission systems
- Detect technical errors
- Ensure proper integration before the actual filing process.
It is essential to review the technical documentation available on the Tax Agency Developers Portal to ensure correct implementation.
Conclusion
The implementation of Pillar 2 in Spain represents a significant development in international taxation, particularly for large corporate groups. A clear understanding of the reporting forms, deadlines and technical requirements will be essential to ensure compliance and avoid issues during the filing process.