Global Minimum Tax 2025: Year-End Deadlines and Tasks for Businesses

Large international and domestic corporate groups, as well as tax professionals dealing with international taxation, have recently been closely monitoring the still-developing Global Minimum Tax (GloBE) regulations. Introduced in Hungary last year, the global minimum tax applies to multinational corporate groups where the ultimate parent company’s consolidated annual revenue reaches or exceeds €750 million in at least two of the four fiscal years immediately preceding the tax year. The regulation aims to ensure that the largest economic players pay taxes more proportionally across the countries in which they operate. Due to the rules’ complexity, the complicated calculations involved, significant administrative burdens, and high penalties for non-compliance, it is strongly recommended to involve experts in tax planning to minimize GloBE-related risks.

This article highlights the year-end deadlines for 2025 and the tasks related to the 2026 fiscal year-end.

November 20, 2025 – GloBE QDMTT Advance Payment

For the first time this year, there is a reporting and payment obligation for the Qualified Domestic Minimum Top-up Tax (QDMTT). For calendar-year taxpayers, the advance payment for the 2024 tax year is due on November 20, 2025, which is approaching rapidly. Early preparation is therefore recommended.

February 28, 2026 – GloBE Notifications

The administrative tasks under GloBE do not end with the advance payment. Affected companies are required to submit an annual notification on a dedicated form to indicate whether they are subject to the GloBE top-up tax and to identify the multinational or large domestic corporate group they belong to. Following a legal amendment in June 2025, the deadline for calendar-year taxpayers to submit notifications for 2025 is February 28, 2026.

June 30, 2026 – Global Minimum Tax Obligations: QDMTT and GloBE Information Return (GIR) Deadlines

In 2026, the first reporting and filing deadlines under the global minimum tax system will occur, marking a milestone in multinational corporate taxation. By this date, companies must submit the QDMTT and the GloBE Information Return (GIR) for the first time. These reports provide detailed information on the tax positions of group members and the actual taxes paid by country. They also identify countries where the corporate group may be under-taxed and indicate where the difference to the internationally expected 15% effective tax rate must be paid. This obligation introduces new challenges for financial and tax planning, not only regarding accurate data collection and calculations but also the coordination of different countries’ rules.

Generally, domestic top-up tax filings must be submitted within 15 months of the end of the tax year, except for companies subject to GloBE for the first time, which have 18 months. For calendar-year taxpayers, the deadline for the 2024 fiscal year is therefore June 30, 2026. Transitional provisions allow some exemptions from additional tax payments, but safe harbour exemptions do not exempt companies from filing obligations. It is important to note that if a company does not apply safe harbour in any year, it cannot opt for it in subsequent years, even if conditions are met.

Corporate groups subject to the global minimum tax must also submit a group-level tax return, the GloBE Information Return (GIR), which is also due on June 30, 2026 for the first filing year (2024). Hungary accepts GIR filings submitted via another country if the submitting country is a signatory to the multilateral GloBE agreement, ensuring that the submitted data is shared with the tax authorities of all participating countries, including Hungary.

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Glossary – Global Minimum Tax (GloBE)

• Global Minimum Tax (GloBE):
  International rules ensuring that multinational groups pay at least a specified minimum effective tax (15%) in the countries where they operate.
• Multinational Corporate Group:
  A company with subsidiaries or permanent establishments in multiple countries, whose consolidated annual revenue meets or exceeds the €750 million GloBE threshold.
• QDMTT (Qualified Domestic Minimum Top-up Tax):
  Domestic top-up tax payable if the actual tax paid in a country falls below the 15% minimum.
• GloBE Information Return (GIR):
  Group-level tax return reporting detailed tax information of all group members and taxes paid by country.
• Notification Obligation:
  Annual administrative task to report GloBE applicability and group membership.
• Global Minimum Tax Deadlines:
  • QDMTT advance payment: Nov 20, 2025
  • GloBE notifications: Feb 28, 2026
  • First GloBE filing and GIR: June 30, 2026
• Calendar-Year Taxpayer:
  Companies whose fiscal year runs January 1 – December 31, with corresponding GloBE deadlines.
• Effective Tax Rate:
  Taxes actually paid as a percentage of profits; GloBE ensures this does not fall below 15%.
• Safe Harbour Exemption:
  Specific relief that may exempt a group from additional top-up taxes, but not from filing obligations.
• Domestic Top-up Tax Filing:
  Submission of QDMTT to the Hungarian tax authority (NAV), detailing the company’s tax position.
• Administrative Obligations under GloBE:
  Tasks such as data collection, completing returns, and meeting deadlines.
• Consolidated Annual Revenue:
  Aggregate revenue of all group members, determining GloBE applicability.
• Multilateral GloBE Agreement:
  International agreement enabling GIR data submitted in one country to be shared with all participating countries’ tax authorities.
• GloBE Tax Planning:
  Planning financial and accounting decisions to minimize GloBE tax and compliance risks.
• Group-Level Coordination:
  Coordination among group members to ensure accurate and timely reporting, filings, and calculations.