KPMG Luxembourg Headquarters in Luxembourg-Kirchberg; Credit: KPMG

KPMG Luxembourg published the latest edition of its "Luxembourg Tax Alert" report on Friday 31 July 2026, highlighting new developments relating to Luxembourg's subscription tax procedures.

According to KPMG, the two-year transition period introduced by the Administration de l'enregistrement, des domaines et de la TVA (AED) following the publication of Circular No. 821 in July 2024 will end on Monday 31 August 2026. The circular introduced new online procedures for filing subscription tax returns for Undertakings for Collective Investment (UCIs), Specialised Investment Funds (SIFs) and Reserved Alternative Investment Funds (RAIFs). From September 2026, investment funds will be required to submit subscription tax returns exclusively through the new online forms available on MyGuichet, while providing additional information as part of their filings.

The changes follow the introduction of new online procedures announced by Luxembourg's indirect tax authorities, the Administration de l'enregistrement, des domaines et de la TVA (AED), in July 2024. During the two-year transition period, taxpayers have been able to use both the previous and the new filing systems in parallel.

KPMG also noted that identifiers for Reserved Alternative Investment Fund (RAIF) compartments, including CSSF and ISIN codes, are now available. Under the new reporting framework, these compartment-level identifiers will form part of the mandatory information to be included in subscription tax returns. Taxpayers who identify missing or incorrect ISIN codes may notify the AED.

In addition, the AED has announced that the Subscription Tax Office will now systematically issue account statements to taxpayers. According to KPMG, the initiative is intended to improve transparency by providing a regular overview of subscription tax positions and helping taxpayers identify any outstanding balances.

The account statements will indicate whether taxpayers have debit or credit balances. Debit balances should generally be settled within fifteen days of receiving the statement, while credit balances may be offset against future subscription tax liabilities. Where a credit balance cannot be fully used within two years, taxpayers may request a refund from the Subscription Tax Office.

KPMG noted that the measures are intended to support the transition to the new reporting framework and improve the administration of Luxembourg's subscription tax system.

The full KPMG Luxembourg report can be found at: https://kpmg.com/lu/en/insights/regulatory-updates/subscription-tax-online-procedures-updates.html