Luxembourg Pillar 2 — Luxembourg tax authorities update FAQs on compliance obligations

Registration obligations: Article 49

Every constituent entity, joint venture (JV) or JV affiliate within scope of the Pillar 2 Law that is located in Luxembourg is required to register in accordance with Article 49, regardless of whether a safe harbour has been applied or whether there is any filing obligation under Articles 50 and 51.

• Investment entities. Any investment entity located in Luxembourg and qualifying as a constituent entity, JV or JV affiliate within the scope of the Pillar 2 Law must register.
• Compartments (sub-funds) of multi-compartment legal entities. A compartment that qualifies as a constituent entity, JV or JV affiliate within the scope of the Pillar 2 Law must register separately and obtain a dedicated Luxembourg TIN from the ACD’s interest withholding tax office. This TIN is for Pillar 2 purposes only and may not be used for any other Luxembourg or foreign filing.
• Stateless entities. Entities with no jurisdiction of location under the Pillar 2 Law are not subject to the registration requirement, as they are not located in Luxembourg by definition.
• Entities created and wound up within the same reporting fiscal year. Both registration and deregistration are required in this scenario. During the transition year, the ACD will exercise administrative leniency and allow deregistration up to 18 months after the end of that year (rather than the usual 15 months), without triggering penalties.
• Group transfers. A constituent entity changing MNE group must formally deregister before re-registering under its new group.

GIR filing exemption and notification procedure: Article 50

Where a Luxembourg constituent entity relies on the exemption from filing a Luxembourg GloBE information return (GIR) — because a qualifying central filing is made in another jurisdiction — it must still notify the ACD of the identity and jurisdiction of the filing entity. The FAQ confirms that this notification is to be made as part of the registration procedure.

For jurisdictions that do not have a qualifying Competent Authority Agreement with Luxembourg in effect by 30 June 2026 but are listed in the OECD’s document on support for central GIR filing and exchange published on 18 May 2026, the ACD, as an administrative leniency, will not require a local GIR filing until 31 December 2026, provided the GIR is filed on time in the relevant jurisdiction. The three jurisdictions currently concerned are Barbados, Switzerland and Turkey. Should the relevant jurisdiction fail to transmit the GIR data to the ACD by 31 December 2026, a local filing will be mandatory.

Next steps

As a reminder, every constituent entity in Luxembourg (including JVs and JV affiliates) that belongs to an MNE group must:

• Register with the ACD and notify it of the designated filing entity within 15 months after the end of the reporting fiscal year (18 months for the transition year).
• File the top-up tax information return and top-up tax (payment) return by the same deadline.
• Pay any top-up tax due within one month of the filing deadline.

For groups witha 2024 financial year corresponding to the calendar year, the registration and filing deadlines fall on 30 June 2026.

The online procedures for Pillar 2 compliance are open on MyGuichet.lu.