Pillar 2 in Switzerland

The OECD/G20 initiative to combat base erosion and profit shifting (BEPS) led to the development of Pillar 2, which provides for a global minimum tax of 15% for multinational companies with an annual turnover of more than 750 million euros. Switzerland is gradually implementing these regulations.

On 22 December 2023, the Swiss Federal Council adopted the ordinance on the introduction of the OECD/G20 minimum taxation with effect from 1 January 2024. Initially, the Qualified Domestic Minimum Top-up Tax (QDMTT) was introduced, while the application of the Income Inclusion Rule (IIR) and the Undertaxed Profits Rule (UTPR) was postponed for the time being. On 4 September 2024, the Federal Council decided to bring the IIR into force from 1 January 2025 to ensure that low-taxed income of foreign group entities of multinational groups domiciled in Switzerland are covered. The introduction of a UTPR has been suspended with for the time being.

Introduction of the OMTax platform

To facilitate compliance with the new tax regulations, Switzerland has developed the
web-based application OMTax. This platform has been available since 1 January 2025 and enables companies to fulfil their tax obligations electronically. The OMTax platform is integrated into the Federal Tax Administration’s ePortal and is available in German, French, Italian and English.

Determination of the responsible constituent entity and registration process

The registration process begins with the identification of the taxable Swiss constituent entity. This determination is made in accordance with Art. 5 of the Swiss Minimum Taxation Ordinance (Mindestbesteuerungsverordnung (MindStV)). If a multinational group has several constituent entities in Switzerland, the top domestic company or the most economically significant constituent entity (including any permanent establishments of foreign companies[¹]) must be identified as the responsible constituent entity. While only one constituent entity is subject to tax at a time, the supplementary Swiss tax due must be distributed among all constituent entities. The allocation is made in accordance with the individual contribution to the top-up tax on the basis of the individual financial statements of these constituent entities. Although the top-up tax is not deductible for income tax purposes, if the constituent entities are not charged in accordance with the principle of origination, this can lead to withholding tax or stamp duty consequences. The identification of the relevant constituent entities and the correct allocation of the expenses for the top-up tax are therefore essential. This must also be taken into account when calculating tax provisions in accordance with the Swiss Code of Obligations.

Registration takes place electronically directly on the OMTax platform and has been possible since 1 January 2025. It can be made directly by the respective group or an authorised representative. After registration, an activation letter is sent with a personalised code that is required to activate the tax return. As processing can take several working days, early registration is recommended. Registration must be completed at the latest before the tax return is submitted, which is due 18 months after the end of the first tax year. For constituent entities that close the financial year on 31 December 2024, the registration and submission of the tax return must therefore be completed by 30 June 2026 at the latest. For future financial years, the tax return must be submitted within 15 months of the end of the financial year.

Current developments in the cantons

With the introduction of the OECD minimum tax, several cantons are discussing adjustments to their legislation in order to maintain tax attractiveness and minimise additional tax burdens for resident companies. Certain cantons are specifically examining location promotion measures, e.g. via qualified refundable tax credits (e.g. Basle-City, Grisons, Lucerne, Zug).

At the same time, the planned allocation of the additional tax revenue between the federal and cantonal level encourages some cantons to consider tax rate increases. On 17 December 2024, the cantonal government of Zug proposed imposing an additional income tax of 3% on profits in excess of CHF 20 million. This proposal was withdrawn by the government on 11 March 2025, but nevertheless shows the dynamics of the current discussion. Lucerne is currently examining a similar additional cantonal income tax. Tax rate increases have already been implemented in the cantons of Basel-Stadt, Geneva, Neuchâtel, Schaffhausen and Vaud, for example. These tax rate changes do not only affect companies subject to the OECD minimum tax.

Practical steps for companies

In order to fulfil the new requirements, companies should take the following steps:

• Verification of applicability: Determine whether your company falls within the scope of the global minimum tax.
• Identification of the responsible constituent entity: Carefully determine the responsible constituent entity in accordance with the legal requirements.
• Early registration: Use the OMTax platform to complete the required registration.
• Burden of the top-up tax: Check the burden of the Swiss top-up tax on individual Swiss constituent entities according to the individual contribution to the top-up tax.
• Review of internal processes: Adapt your internal compliance and reporting processes to the new requirements.
• Obtaining expert advice: Consult tax experts to ensure that all obligations are met correctly and to minimise potential tax risks

Conclusion

The introduction of the global minimum tax poses new challenges for companies in Switzerland. The OMTax platform provides an efficient solution to fulfil compliance requirements. Nevertheless, it is essential to be fully aware of the specific obligations and deadlines and to take appropriate measures to avoid tax risks. A proactive approach and expert advice are crucial here.

[¹] In a communication dated 18 March 2025, the Swiss Federal Tax Administration clarified that the tax and procedural obligations, as well as the liability for permanent establishments of foreign companies, apply to the foreign parent company.