Luxembourg court considers economic substance in interest-free loans decision

International Tax Review is part of Legal Benchmarking Limited, 1-2 Paris Garden, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

Luxembourg court considers economic substance in interest-free loans decision

Sponsored by

Sponsored_Firms_deloitte.png
Zero per cent displayed using euro notes.jpg

Dinko Dinev and Iva Gyurova of Deloitte Luxembourg analyse a landmark ruling on how economic substance plays a key role in determining whether interest-free loans from indirect shareholders constitute debt or equity for Luxembourg tax purposes

On April 17 2025, the Luxembourg Administrative Court made a pivotal decision in case No. 50602C. The judgment clarified whether an interest-free loan from an indirect shareholder constitutes debt or equity for tax purposes. Building on previous cases concerning interest-free loans, this ruling provides new insights into how to apply the principle of economic substance.

Case overview

In 2015, an international group’s Luxembourg-based company received two interest-free loans from its indirect shareholder. These were intended to finance the company’s investment in foreign entities involved in a gas pipeline project.

The Luxembourg tax authorities recharacterised these loans as hidden equity contributions due to their economic aspects and their meeting non-arm’s-length criteria. The court upheld the tax authorities’ position.

Court’s analysis

Central to the case was whether the interest-free loans should be recognised as genuine or considered disguised capital. The court applied the substance-over-form principle prevalent in Luxembourg tax law, scrutinising the loans’ contractual features, economic context, and purpose.

The analysis determined that no fixed formula exists to classify financing as debt or equity. Instead, a holistic approach that considers numerous legal and economic elements was applied. The court considered the following key points:

  • Absence of interest – viewed as economically implausible in an arm’s-length setting;

  • Repayment terms – the 10-year maturity of the loans did not align with the long-term nature of the underlying project funded by these loans;

  • Fund allocation – the loaned funds were directed towards long-term investments in companies developing infrastructure;

  • Absence of guarantees or collateral – no security was provided, making the arrangement inconsistent with arm’s-length conditions given the borrower’s highly leveraged position; and

  • Extreme indebtedness – at 99.99%, the debt-to-equity ratio was far beyond acceptable levels.

The last three points are examined below as they clarify how the substance-over-form principle is applied to intragroup loans under Luxembourg jurisprudence.

Fund allocation

The fact that loan proceeds were allocated to long-term shareholding in entities developing energy infrastructure was a pivotal consideration. The court noted that such investments, characterised by high initial capital costs and uncertain revenues, align more closely with equity financing due to the higher risk-return profiles, unlike debt financing, which demands predictable, regular servicing.

While examples of debt-financed long-term assets exist in the market, taxpayers must demonstrate a convincing economic rationale for using intragroup debt that considers both lender and borrower perspectives – especially within volatile and unpredictable cash flow scenarios.

Absence of guarantees

Lack of guarantees was another significant factor. In the court’s view, an arm’s-length lender would have required a repayment guarantee, particularly given the borrower’s low equity and high financial risk.

Nonetheless, the absence of guarantees was not deemed determinative by itself. This nuance is particularly important in intragroup lending, where the need for guarantees is not always obvious due to the lender’s existing control or influence over the borrower and the prevalence of external, already secured funding.

Excessive debt leverage

The court also took issue with the borrower’s excessive debt leverage. An independent lender would never accept such high exposure to a minimally capitalised borrower incapable of absorbing losses; to do so would suggest a risk appetite akin to that of a shareholder.

The taxpayer’s argument that its capital structure mirrored market practices was rejected: the court found the transfer pricing benchmarks unreliable due to scarce, poor-quality comparable data. The taxpayer’s view that only part of the loans exceeding 85% of the borrower’s assets should be reclassified into equity was dismissed. Instead, the court stated the supposed 85:15 debt leverage ratio lacked legal force and emphasised the need for a proper economic analysis to make a holistic assessment of the debt qualification. The court made it clear that the question at hand was not about the tax treatment of excessive debt but about qualifying the instrument itself as debt or equity.

Key takeaways for taxpayers

It was the interest-free status that heavily influenced the court’s closer examination of the loans, determining if they represented equity. The ruling underscores the need for careful, fact-driven assessment of multiple criteria.

The court’s decision also reinforces the importance of debt capacity analysis. First, debt capacity, in combination with the other criteria discussed, plays a key role in making a holistic, binary assessment of whether a financing instrument qualifies as debt or equity. Second, when a financing instrument is correctly qualified as debt, a debt capacity analysis – applied on its own – can indicate the specific amount to be treated as debt under the arm’s-length principle.

The final takeaway is clear: taxpayers should not only ensure their intragroup loans carry arm’s-length interest but also be ready to demonstrate that the debt capacity and commercial viability of the adopted terms and conditions are consistent with the overall economic context and business purpose of the loans.

more across site & shared bottom lb ros

More from across our site

The acquisition of a two-partner practice from Stephenson Harwood means that Charles Russell Speechlys has the largest private client team in Asia, the firm claimed
Complex and constantly shifting rules on global mobility mean ‘the risk is too great’ for staff to work abroad on personal time, EY’s Maureen Flood tells ITR
While it’s great that the OECD is alive to multinationals’ fears of being caught in a compliance trap, the ‘common understanding’ illustrates a worrying lack of readiness
Rising demand for specialist expertise has fuelled the growth in tax partner headcounts, Cain Dwyer found; in other news, Switzerland has been urged to reconsider pillar two
An OECD report on the taxation of the digital economy is expected by the end of 2026, according to the group of nations
Trophy assets are evolving from personal indulgences to structured investments, prompting family offices to prioritise tax efficiency, governance discipline, and cross-border compliance
As demand for complex, cross-border private client counsel spikes, Patrick McCormick sees opportunity in starting from scratch
As part of an exclusive global alliance, KPMG will become one of Anthropic’s ‘preferred consultants’ for private equity
In the second part of this series, the focus shifts to how taxpayers can manage ongoing risks across the lifecycle of cross-border structures
Jurisdictions have moved to ensure that multinationals are not punished for late GIR filings due to a lack of available filing portals or exchange relationships
Gift this article