Topical information on the minimum tax for large-scale corporate groups: using MyTax to file the return, changed legal rules going into effect

The minimum tax concerns large corporate groups. The objective is to ensure that at least a minimum tax level is applied around the world. Reporting obligations will be imposed on MNE groups with revenues indicated by consolidated financial statements exceeding €750 million a year, for at least two of the latest four accounting periods. In addition, domestic group enterprises with annual turnover exceeding a national threshold in their EU member state must submit the returns.

The due date for the first returns relating to the minimum tax is in June 2026. Returns can be submitted in MyTax as of 30 January 2026 Finland’s legal rules to reflect the recent changes (DAC9) to the Directive on Administrative Cooperation have entered into force. As the new rules are implemented in the European Union, the scope of the automatic exchange system for tax information between member states will also cover the top-up taxes. Additional amendments to Finnish tax rules include new provisions on advance rulings and harmonisation.

Returns related to the minimum tax can be submitted in MyTax as of 30 January 2026

Corporate groups will need to file a set consisting of three reports in MyTax: the GloBE information return – GIR, the Notification of the filing constituent entity, and the Top-up tax return. Returns can be submitted in MyTax as of 30 January 2026. 

The data content is based on an OECD standard on the GloBE information return (GIR). You upload these returns as .xml files through MyTax. As for the Notification of the filing constituent entity and the Top-up tax return, you can fill in the relevant MyTax fields instead of uploading a file.

All of the above returns must be submitted within 15 months after your accounting period end date. For the first submission, the due date is postponed to 18 months from the end date. The first due date will be 30 June 2026.

The EU Directive’s impact is an expansion of the automatic exchange of information

The Finnish parliament adopted the new Act to enforce the latest changes to the Directive on Administrative Cooperation. The changed reporting rules do not require MNE groups to submit a report on their minimum tax to every member state one by one. 

This change is based on the amended Directive on Administrative Cooperation with its extended information-exchange provisions that will now cover the information with regard to large-scale corporate groups’ minimum tax. The changed reporting rules will mean a less stringent requirement on corporate groups to submit reports.  This means that the sending of information returns can be centralised to a single constituent entity of the group, either the parent company or a designated filing entity. As a consequence, the compliance burden will be less heavy.

Changes embodied in a Government proposal to facilitate issuance of advance rulings

The government proposes a set of changes to the act on the minimum tax rate for large-scale groups. The changes included in the Government proposal would harmonise domestic regulation with the international guidelines that were agreed upon in 2024 and 2025. In addition, business enterprises could submit applications for advance rulings regarding the minimum tax in respect of accounting years with a start date 1 January 2024 or later. The Government proposal also aims for adding a provision against tax evasion to the Act, to prevent various arrangements to evade the minimum tax. The anti-evasion rules would be applied to accounting periods starting 1 January 2027 or later. The planned legislation is expected to come into force soon.

Read more: 

Minimum tax rate for large-scale groups (OECD Pillar Two)

Hallituksen esitys HE 142/2025 vp (in Finnish and Swedish)

Hallituksen esitys HE 196/2025 vp (in Finnish and Swedish)