EU DG TAXUD Wealth Tax Study: What Accounting Firms Must Know

The European Commission's Directorate-General for Taxation and Customs Union (DG TAXUD) published a major two-volume study on wealth taxation on 15 April 2026. It covers net wealth taxes, capital taxes, and exit taxes across EU Member States and selected non-EU countries. For accounting firms and CFOs advising high-net-worth or ultra-high-net-worth clients, the findings carry direct implications for compliance strategy, cross-border structuring, and how tax administrations are likely to evolve their enforcement tools in the near term.

What the Study Covers

Scope and Structure

Commissioned by the European Commission in 2024 against the backdrop of active discussions at the OECD, G20, and United Nations, the study was designed to inform the policy debate rather than prescribe a particular approach. It is structured around two volumes with distinct but complementary purposes.

Volume one surveys academic and empirical literature across five categories of wealth-related taxes, then maps the existing regimes across EU Member States. The mapping exercise identified both areas of research consensus and areas where the evidence base remains thin, particularly regarding how ultra-high-net-worth individuals respond to international tax differentials.

Volume two is built around case studies. The Commission examined four Member States in depth: Austria, France, Germany, and Spain. Three non-EU jurisdictions were also analysed: Norway, Switzerland, and Colombia. Each case study was chosen because the jurisdiction currently has, or has recently had, a form of wealth tax, making it possible to draw comparisons on design choices and outcomes.

Five Tax Categories

The study organises wealth-related taxes into five categories. While the full taxonomy is set out in the document itself, the grouping spans net wealth taxes (levied on total assets minus liabilities), inheritance and gift taxes, capital taxes applied at a transaction or periodic level, real estate taxes, and exit taxes triggered when taxpayers change residence or transfer assets out of a jurisdiction. Exit taxes are of particular relevance to advisers working with clients who hold significant illiquid or unrealised positions, including in digital assets.

Key Findings on Revenue and Equity

Wealth Taxes Have Not Been a Major Revenue Source

One of the study's clearest conclusions is that the wealth taxes examined have, in practice, generated limited revenue relative to expectations. The research points to tax gaps as the primary explanatory factor. Those gaps arise from three overlapping causes: statutory tax reliefs, explicit exemptions built into the legislation, and inadequate compliance by taxpayers. This is not a minor technical footnote. It means that the gap between what wealth taxes theoretically yield and what they actually collect is significant, and that the design of the tax is as important as its existence.

Tax Design Shapes Outcomes More Than Rate

The case study analysis shows that whether a wealth tax achieves its horizontal and vertical equity objectives depends heavily on how it is designed and how taxpayers respond. A high nominal rate paired with wide exemptions and weak third-party reporting can produce less revenue and less redistribution than a lower-rate regime with robust data infrastructure. This finding has direct relevance for firms advising clients on cross-border structuring: the effective burden varies considerably between jurisdictions even where headline rates look comparable.

Compliance Gaps and Information Exchange

What the Study Identifies as Structural Weaknesses

The study is explicit that information exchange is a critical lever. It highlights the importance of effective exchange of information on beneficial ownership, on real estate registration, and on broader asset registration systems. Where those systems are fragmented or incomplete, tax administrations lack the visibility needed to close compliance gaps, regardless of the statutory rules in place.

This observation aligns with the direction of travel at the EU level more broadly. Beneficial ownership transparency has been a recurring theme in anti-money-laundering legislation, and the same data infrastructure question arises in the context of DAC8, which extended the EU's automatic exchange of information framework to crypto-assets. Firms that already operate crypto compliance reporting workflows will recognise the pattern: the quality of third-party data and the digitalisation of the receiving authority both constrain what is practically enforceable.

Periodic Publication of Tax Gaps as a Compliance Tool

One policy recommendation that stands out is the suggestion that periodic, public publication of tax gap estimates could itself incentivise voluntary compliance. The logic is that when taxpayers and their advisers can see the scale of non-compliance in aggregate, the social and reputational calculus around disclosure shifts. Several Member States already publish tax gap estimates for VAT; extending that practice to wealth-related taxes would be a meaningful step, though the study stops short of prescribing it as a requirement.

Digitalisation of Tax Administrations

A Structural Theme Running Through the Study

Alongside information exchange, the study highlights the role of institutional factors, specifically third-party reporting obligations and the digitalisation of tax administrations. These are not treated as optional enhancements. The analysis positions them as conditions for wealth taxes to function as intended. Where administrations lack the digital infrastructure to cross-reference third-party data against self-reported returns, compliance gaps persist regardless of legislative intent.

For accounting firms, this has a practical implication. As EU and OECD-aligned jurisdictions invest in more capable tax administration platforms, the data trails generated by client transactions, including digital asset transactions, become more readable by authorities. Firms using EU ViDA implementation and what it signals for digital tax infrastructure as a reference point will see the same institutional trend at work. The study reinforces that direction. Robust digital asset accounting software and crypto bookkeeping software are no longer optional for practices with exposure to this client segment; they are part of the basic infrastructure for defensible compliance positions.

Mobility Evidence and Its Limits

The study does find some evidence that net wealth taxes and inheritance and gift taxes influence the intranational mobility of individuals. However, it is careful to note that the evidence on international mobility of ultra-high-net-worth individuals is limited. This is a meaningful distinction for advisers. The assumption that wealthy clients will simply relocate in response to wealth tax regimes is not strongly supported by the available data across the jurisdictions studied, though the study acknowledges this is an area requiring further analysis rather than settled science.

Implications for Accounting Firms and CFOs

Four Areas to Monitor

Based on the study's findings, accounting firms and in-house finance teams should pay attention to four converging developments.

First, exit tax exposure deserves a fresh look for any client with significant unrealised positions in any asset class, including digital assets, who is considering a jurisdiction change. The case studies show that exit tax design varies considerably and that the gap between statutory rules and effective enforcement is closing as data exchange improves.

Second, beneficial ownership transparency is moving from an AML-adjacent concern to a core wealth tax compliance concern. The study's emphasis on asset and beneficial ownership registries as prerequisites for effective wealth taxation means that advisers need to treat these registers as live compliance inputs, not background context. This connects directly to the Cyprus IIR qualified status under the EU Pillar 2 Directive, which similarly depends on cross-jurisdictional data completeness to function as designed.

Third, the case for investing in capable crypto accounting software and digital asset accounting software strengthens as tax administrations become more sophisticated. The study's argument that digitalisation of tax administration is a structural condition for compliance effectiveness applies to both sides of the relationship: the authority and the adviser.

Fourth, tax gap publication, if it becomes a standard practice across Member States, will change the political context in which wealth tax policy is debated. Firms advising on structures that rely on exemptions or reliefs should document the legitimate basis for those positions clearly, because public visibility of aggregate gaps tends to be followed by legislative scrutiny of specific relief categories.

Source: European Commission DG TAXUD