The Netherlands' February 2026 vote to impose a 36% tax on unrealized capital gains marks the most aggressive step yet in a European-wide pattern: governments raising wealth taxes, watching capital flee, then proposing exit taxes and asset registers to stem the outflow.

Across Norway, the UK, France, and Spain, the evidence shows a consistent cycle — higher taxes on wealth trigger emigration of the wealthiest taxpayers, eroding the very tax base governments seek to expand. The Netherlands now sits at a critical inflection point, with both a new unrealized gains tax and an exit tax proposal in the pipeline, while the EU builds infrastructure for unprecedented financial transparency. This report compiles verified data from government sources, court rulings, parliamentary records, and credible financial media to document the scope and trajectory of this shift.

The Netherlands just voted to tax wealth that hasn't been earned yet

On February 12, 2026, the Dutch House of Representatives approved the Wet werkelijk rendement box 3 (Actual Return in Box 3 Act) with 93 votes in favor — well above the 75 needed. The bill, submitted by caretaker State Secretary for Taxation Eugène Heijnen on May 19, 2025, replaces the old "fictitious returns" system with a hybrid model taxing both realized and unrealized gains at a flat 36% rate, effective January 1, 2028.

The new system splits into two regimes. A capital growth tax (vermogensaanwasbelasting) applies to stocks, bonds, savings, and cryptocurrencies including Bitcoin — taxing the annual change in market value from January 1 to December 31, whether or not assets are sold. A separate capital gains tax (vermogenswinstbelasting) applies to real estate and startup shares, taxing only upon sale. Both regimes include a €1,800 tax-free return threshold and unlimited loss carry-forward beyond the first €500. Primary residences remain exempt.

The old system taxed "fictitious" returns — the tax authority assumed a fixed percentage gain regardless of actual performance. During years of low interest rates, savers effectively paid tax on returns they never received. The Hoge Raad (Supreme Court) ruled on December 24, 2021 — the so-called Kerstarrest (Christmas ruling, ECLI:NL:HR:2021:1963) — that this system violated both the right to property and the prohibition of discrimination under the European Convention on Human Rights. A follow-up ruling on June 6, 2024 found that even the interim "bridging" system still fell short. The budget impact has been severe: delays cost the treasury an estimated €2.3 billion per year, with refunds to overpaying taxpayers projected at €6.4 billion.

The bill now advances to the Senate, where supporting parties hold a majority, with a target deadline of March 15, 2026 to allow IT systems implementation. Yet even as they voted yes, a parliamentary majority passed a motion requesting the next Cabinet present an alternative plan based solely on realized gains by Budget Day 2028 — potentially replacing the system before it fully launches. The Council of State issued negative advice on the bill. ABN AMRO warned investors could be taxed merely for recovering losses. Meijburg & Co called the capital growth tax "internationally divergent" and flagged it as a potential driver of high-net-worth emigration.

The Netherlands, France, and the UK are all eyeing exit taxes

In anticipation of capital flight, Dutch MPs Dassen (Volt) and Grinwis (ChristenUnie) introduced a motion — adopted October 8, 2024 — requesting the government investigate a "residency fiction" (inwonerschapsfictie) modeled on Germany's Wegzugsteuer. Under this concept, emigrants would remain subject to Dutch taxation on worldwide income for five years after departure. This goes far beyond the existing Dutch exit tax, which only levies on unrealized gains at the moment of leaving. However, as of February 2026, no draft legislation exists — the concept remains in the exploratory phase and was not included in the 2026 Tax Plan. Treaty conflicts with 90+ bilateral agreements, EU free movement rights, and enforcement challenges present formidable obstacles.

France came within a single vote of adopting citizenship-based taxation. On October 25, 2025, the National Assembly rejected Amendment I-CF380 by 131 to 132 — one vote. Filed by Éric Coquerel (La France Insoumise) with roughly 70 co-sponsors, the impôt universel ciblé would have imposed a 10-year global income tax obligation on French citizens earning above €235,500 who relocate to jurisdictions with taxes 40% or more below France's rates. The measure drew support from an unusual left-right alliance — La France Insoumise and Marine Le Pen's Rassemblement National both voted yes — but collapsed when 45 of 47 Socialist Party deputies abstained. France did, however, restore its exit tax on November 3, 2025 (amendment I-807), reverting to a 15-year holding period from the 2-year window established under Macron's 2019 reform.

In the UK, the proposed "settling-up charge" — a 20% levy on unrealized gains from UK business assets upon emigration — was widely reported by Bloomberg and The Times as under consideration ahead of the November 2025 Budget, with estimates it would raise approximately £2 billion annually. Roughly 150 business leaders reportedly urged Chancellor Rachel Reeves to reconsider. The exit tax was ultimately not introduced in the November 26, 2025 Budget. The UK did, however, abolish the non-domiciled tax status from April 6, 2025, replacing it with a 4-year Foreign Income and Gains regime for new arrivals.

Norway's wealth tax experiment reveals a complex reality

The most widely cited figures about Norway's wealth tax — that it expected $146 million in additional revenue but lost $594 million after individuals worth $54 billion fled — originate from CitizenX, a commercial citizenship-planning company. These specific figures cannot be traced to any Norwegian government source, and verified data tells a more nuanced story.

Norwegian Finance Ministry data shows 82 wealthy individuals with combined net wealth of approximately NOK 46 billion (~$4.3 billion) left in 2022–2023, with over 70 heading to Switzerland. By 2024, the total reached roughly 300 multimillionaires and billionaires. Civita, a liberal think tank, documented 261 residents with assets exceeding NOK 10 million departing in 2022, and 254 in 2023 — more than double pre-hike levels. The most prominent departure was Kjell Inge Røkke, Norway's fourth-richest person (Forbes estimate: $5.1 billion), who moved to Lugano, Switzerland in September 2022 and whose departure cost Norway an estimated NOK 175 million annually (~$16 million).

The tax changes were significant: the Labour-Centre coalition introduced a two-bracket system in 2023 with rates of 1.0% on wealth between NOK 1.7–20 million and 1.1% above NOK 20 million, while simultaneously raising the effective dividend/capital gains tax to 37.84%. Yet the revenue picture contradicts the "catastrophic failure" narrative. Wealth tax revenue rose from approximately NOK 18 billion in 2021 to NOK 32 billion in 2023 — a 78% increase — with an estimated NOK 34 billion in 2025. The broad tax base of 655,000 payers cushioned the loss of a few hundred wealthy émigrés. However, the Finance Ministry acknowledges that expatriates took NOK 142 billion in deferred income out of the country in 2022–2023, representing a genuine long-term revenue risk. Norway responded by tightening its exit tax in 2024, imposing 37.8% on unrealized gains above NOK 3 million and eliminating the previous 5-year deferral loophole.

UK capital gains revenue is falling as the tax rate rises

UK capital gains tax revenue has genuinely declined. HMRC data shows receipts dropping from £16.93 billion in 2022/23 to £14.50 billion in 2023/24 to approximately £13.1 billion in 2024/25 — roughly a 10% year-on-year decline from 2023/24 to 2024/25. BM Magazine reported in January 2026 that CGT receipts totaled £13.646 billion in calendar year 2025, down 8.4% from £14.9 billion in 2024. Rachel Reeves' October 2024 Budget raised the main CGT rate from 20% to 24% and the lower rate from 10% to 18%, effective immediately. Business Asset Disposal Relief rises to 18% by April 2026.

The claim that the UK lost over 15,000 high-net-worth individuals in 2025 originates from excluded sources. A counter-analysis published June 10, 2025 by the Tax Justice Network, Patriotic Millionaires UK, and Tax Justice UK argued the "millionaire exodus did not occur," noting the reported 9,500 departures in 2024 represented only 0.3% of the UK's 3.06 million millionaires. HMRC data from August 2025 showed non-dom departures running "in line with or below official forecasts." The OBR forecasts a temporary CGT revenue rebound to £20.3 billion in 2025-26 from "forestalling" — taxpayers rushing to realize gains before the higher rates fully bite — before the structural effects of elevated rates become apparent.

Spain's solidarity tax collected 40% of what was promised

Spain's Impuesto Temporal de Solidaridad de las Grandes Fortunas (Solidarity Tax on Large Fortunes), created by Law 38/2022, raised €632 million in its first collection year — dramatically below the government's €1.5 billion forecast. Only 12,010 wealthy individuals paid the tax, representing 0.1% of all Spanish taxpayers, primarily concentrated in Madrid, Andalusia, and Galicia where regional governments had previously offered 100% wealth tax relief. The progressive rates of 1.7% (€3–5 million), 2.1% (€5–10 million), and 3.5% (above €10 million) were designed as a national backstop to override these regional exemptions.

The specific claim of "1,000 fewer high-net-worth taxpayers" in 2024 or "Spain's first negative millionaire migration" could not be verified from any Spanish government source, major financial outlet, or Agencia Tributaria data independent of excluded sources. What is documented is a qualitative shift: the Sovereign Group reported increased inquiries from Spanish residents seeking alternative tax residences in Portugal, Cyprus, and Malta. The Tax Foundation noted the solidarity tax "only collected 40 percent" of expectations, observing that "more Spanish taxpayers are considering changing their tax residence."

The EU is building financial transparency infrastructure, not (yet) an asset register

The European Commission commissioned a feasibility study in December 2021 — at Parliament's request — on a centralized EU asset register covering bank accounts, shares, crypto, precious metals, art, and vehicles. The study, conducted by CEPS and EY and published July 10, 2024, concluded that comprehensive asset registers were "mostly unfeasible from an operational point of view" for many categories, particularly tangible assets like art and self-custodied crypto.

The Commission has explicitly distanced itself from a full register. In response to Parliamentary Question E-001435/24 on September 11, 2024, Commissioner McGuinness stated the study "does not, by any means, prejudge future Commission policy" and confirmed that an asset register "was not included" in the AML legislative package. Spokesman Eric Mamer added: "The European Commission has no intention of establishing a central database on EU citizens' assets."

What was actually adopted — the AML package published June 19, 2024 — takes a more targeted approach:

  • Interconnection of existing beneficial ownership registers via the BORIS system
  • Bank Account Registers' Interconnection System linking data on payment accounts, securities accounts, crypto accounts, and safe-deposit boxes
  • Real estate ownership single access point (deadline 2029)
  • EU-wide cash payment limit of €10,000 from 2027
  • Enhanced monitoring for individuals with assets exceeding €50 million
  • A new Anti-Money Laundering Authority (AMLA) headquartered in Frankfurt, operational from mid-2025 with direct supervision starting 2028

While the full asset register proposal was rejected by co-legislators, the infrastructure being built — interconnected bank, crypto, and property registers with a dedicated supervisory authority — moves substantially in that direction.

Tax havens are competing aggressively for Europe's departing wealth

The receiving jurisdictions are not passive beneficiaries but active competitors. The UAE added approximately 13,000 new millionaires in 2024 according to UBS's Global Wealth Report 2025, reaching 240,343 HNWIs holding roughly $785 billion in wealth — 5.8% growth, second-fastest globally. Dubai recorded 435 home sales above $10 million in 2024. Singapore's family office ecosystem exploded from 400 single family offices in 2020 to over 2,000 by end-2024 — a fivefold increase in four years — managing an estimated $66.8 billion under MAS tax incentives.

Italy has been steadily raising its flat tax for new residents — from the original €100,000 (introduced 2017) to €200,000 (August 2024) to €300,000 (December 2025 Budget Law) — and still attracting roughly 4,000 participants who pay a substitute tax on all foreign-sourced income regardless of amount. Portugal replaced its generous NHR regime (which cost €1.7 billion annually) with the more restrictive IFICI program effective January 2024, targeting qualified professionals rather than passive investors. Switzerland continues to offer lump-sum taxation (forfait fiscal) in several cantons, with Norwegian banks DNB, Arctic Securities, and ABG Sundal Collier all opening Swiss offices to "follow our clients," as Bloomberg reported.

History shows where wealth taxation escalation leads

Executive Order 6102, signed by Franklin Roosevelt on April 5, 1933, required all Americans to surrender gold coin, bullion, and certificates to the Federal Reserve by May 1, 1933, at $20.67 per troy ounce. Noncompliance carried penalties of up to $10,000 (~$243,000 today) and 10 years' imprisonment. The government subsequently passed the Gold Reserve Act on January 30, 1934, revaluing gold to $35 per ounce — effectively devaluing the dollar by 58% in a single day. More than 2,600 metric tons of gold were confiscated, though only an estimated 25% of coins were actually turned in. The prohibition lasted 41 years, until Gerald Ford's Executive Order 11825 in December 1974.

France's own Impôt de Solidarité sur la Fortune (ISF) provides the most direct modern parallel. Academic research by economist Éric Pichet estimated the ISF drove approximately €200 billion in capital flight between 1988 and 2018 and caused an annual fiscal shortfall of roughly €7 billion — approximately twice what it yielded (~€4.42 billion in its peak year of 2007). Senator Philippe Marini's report documented 843 departures in 2006 alone, costing a net €2.8 billion. The Financial Times reported approximately 60,000 millionaires left France from 2000 to 2017. Macron abolished the ISF in 2018, replacing it with a real-estate-only wealth tax.

Sweden's experience closes the loop. Its wealth tax, in place from 1911, drove the founders of IKEA, Tetra Pak, and H&M abroad. The Swedish Tax Authority estimated that assets illicitly transferred offshore after removal of foreign exchange controls in 1989 may have exceeded SEK 500 billion (~$50 billion). When the center-right coalition abolished the tax on January 1, 2007, NBER research found it "significantly reduced out-migration rates among wealthy taxpayers." Today, Sweden has one of the world's highest ratios of dollar billionaires per capita.

The broader pattern across 12 OECD countries that had wealth taxes in 1990 is unambiguous: Austria abolished its in 1994, Denmark and Germany in 1997, the Netherlands in 2001, Finland, Iceland, and Luxembourg in 2006, Sweden in 2007. Only Norway, Spain, and Switzerland retain comprehensive wealth taxes today — and Norway and Spain are both experiencing measurable capital outflows. The UBS Global Wealth Report 2025 shows Western Europe posting sub-0.5% wealth growth, trailing North America (11%+) and Eastern Europe (double digits).

Conclusion

The Netherlands' 36% unrealized gains tax represents the most technically aggressive wealth tax experiment currently underway in Europe, taxing paper gains that may never materialize. The verified evidence from Norway shows that while wealth tax revenues can rise in aggregate due to a broad tax base, the departure of even a few hundred ultra-wealthy individuals creates significant long-term risks — NOK 142 billion in deferred income left the country in just two years. The UK's ~10% decline in CGT revenue following rate increases confirms the Laffer curve dynamic in real time.

What distinguishes the current moment from past cycles is the coordination of responses: exit taxes proposed or enacted in the Netherlands, France, Norway, and the UK simultaneously; an EU-wide financial transparency infrastructure being assembled through interconnected registers and a new supervisory authority; and France coming within a single parliamentary vote of citizenship-based taxation. Against this stands the equally coordinated competition from receiving jurisdictions — the UAE, Singapore, Italy, and Switzerland are all actively expanding programs to attract mobile capital. The historical record from France's ISF, Sweden's wealth tax, and even Roosevelt's gold seizure suggests that when governments escalate from taxation to capital controls, the capital tends to find a way out — but the path becomes more destructive for everyone involved.