Luxembourg’s tax authorities have reminded entities covered by the Pillar Two Law to complete their registration and supplementary tax filing obligations within the prescribed deadlines.
Luxembourg’s Direct Tax Administration has urged constituent entities, joint ventures and entities affiliated with joint ventures to regularise outstanding Pillar Two filing obligations as soon as possible. In a 6 August 2026 reminder, the authority highlighted registration, information-return and supplementary-tax return requirements under the country’s effective minimum taxation rules, with all procedures required to be completed online through MyGuichet.lu.
Filing obligations
The Pillar Two Law introduced several filing obligations for entities within its scope. These include registration with the Direct Tax Administration, submission of an information return for the supplementary tax and submission of a return concerning the supplementary tax.
Where an exemption from filing an information return applies under Article 50(3) of the Pillar Two Law, the entity must instead notify the identity of the entity filing the return and the jurisdiction in which it is located.
All procedures relating to registration, the information return for the supplementary tax and the supplementary tax return must be completed exclusively online via MyGuichet.lu.
The Direct Tax Administration has made technical specifications for the filing procedures and a FAQ available on its website.
Deadlines and sanctions
The filing obligations must be fulfilled within the deadlines set out in Articles 49 to 51 and 56 of the Pillar Two Law.
Failure to comply with the filing obligations may result in sanctions under the Pillar Two Law.
The reminder comes as jurisdictions implementing the Global Minimum Tax continue to address the practical compliance requirements associated with Pillar Two filings. The OECD has also issued guidance aimed at supporting compliance and preserving the administrative benefits of central filing for the GloBE Information Return (GIR).
Earlier, Luxembourg introduced a draft law to implement the OECD/G20 Inclusive Framework’s Pillar Two Side-by-Side package.
