The Structural Reform of Box 3 and Its Application to Crypto Assets

Introduction:

The Netherlands is preparing one of the most consequential reforms of wealth taxation in Europe. Through the proposed “Wet werkelijk rendement” (Bill 36 748), the traditional deemed-return system in Box 3 will be replaced by taxation based on actual returns. The reform is scheduled to enter into force on 1 January 2028. Under the new system, taxation no longer relies on assumed yields. Instead, individuals will be taxed on the real economic income generated by their assets. The official factsheet explicitly states that the system taxes the “werkelijke inkomsten die iemand heeft uit vermogen” Factsheet nieuw stelsel box 3. This includes interest, dividends, rental income, sale gains, and importantly, annual value development of investments and other assets.

The Crypto reform

Crypto-assets are expressly included within the scope of “overige bezittingen (o.a. crypto)” Factsheet nieuw stelsel box 3. As a consequence, they fall fully within Box 3. The calculation follows a structured mechanism. First, all actual income from assets is aggregated. This includes annual value increases, whether realised or not. Second, allowable costs are deducted. Third, a tax-free income threshold is applied, currently set at €1,800. The remaining taxable income is subject to a flat 36% rate Factsheet nieuw stelsel box 3.

The most transformative feature of the reform is the taxation of unrealised gains. An unrealised gain arises when an asset increases in market value but has not been sold. Under the new regime, this appreciation is included in the annual taxable result. The factsheet illustrates this principle through examples where the annual result is calculated as:

Income at the end of the year – Income at the begining of the year – deposits + withdrawals. Factsheet nieuw stelsel box 3.

In practical terms, if a taxpayer holds crypto that increases in value during the year, the appreciation becomes part of the taxable base, even if no disposal occurs. This converts Box 3 into a wealth accrual system rather than a pure capital gains system. The nexus for taxation remains Dutch tax residency. Resident individuals are taxed on their worldwide Box 3 assets, including crypto held on foreign exchanges or in private wallets. The system is therefore residence-based and global in scope.

The parliamentary debate reveals that this accrual-based model was deliberate. Motions requesting a shift toward a pure realisation-based capital gains tax were rejected blg 1233092. The government argued that a full capital gains regime would create significant budgetary losses in the early years and incentivise long-term tax deferral blg-1233092. The flat 36% rate and accrual methodology were retained to ensure fiscal neutrality and stability. The starting point for tax imposition is therefore the annual net result after costs, above the €1,800 tax-free threshold. This marks a clear structural break from most international crypto tax systems.

II. Losses, Deductions, and the Crypto Tax Base

Given the volatility of crypto-assets, the treatment of losses and deductions becomes central. Under the proposed regime, losses exceeding a defined threshold of €500 may be carried forward to offset future gains Factsheet nieuw stelsel box 3. The carryforward is unlimited in time. However, parliamentary amendments proposing a one-year carryback were rejected (blg-1233092). Consequently, a loss in a subsequent year cannot reduce tax already paid in a prior year.

This is particularly relevant for crypto investors, whose portfolios may fluctuate significantly. A substantial loss in one year may be carried forward, but it does not retroactively correct prior taxation of gains. The tax base for crypto includes annual appreciation, realised gains, and yield-based income such as staking rewards. Against this base, certain costs are deductible. The factsheet confirms that transaction and advisory costs related to the purchase and sale of investments are deductible Factsheet nieuw stelsel box 3. In the crypto context, this may include exchange fees, custody charges, and possibly wallet related service fees, provided they qualify under the statutory criteria. If crypto holdings are debt-financed, interest on that debt may be deductible, subject to general rules applicable to Box 3 liabilities. The result is a system that taxes net economic income from crypto on an annual accrual basis, while allowing forward compensation of losses above the statutory threshold.

III. Industry Criticism, Annual Mechanics, and Market Dynamics

As the Dutch legislature has progressed with the Box 3 reform, moving toward a 36 % tax on actual returns including unrealised gains on savings, investments, and crypto assets beginning 1 January 2028, the proposal has provoked robust criticism from industry analysts, crypto community members, and market observers. Critics frame the annual taxation of unrealised gains not merely as a technical shift in measurement but as a fundamental departure from established investment norms and liquidity realities .

Under the proposed regime, the tax is calculated not on a sale event but on the annual change in market value of an asset. For crypto, which is notoriously volatile, this means that holders could owe tax on value increases at calendar-year end even if they have not realised cash through sale. Binance and other commentators have described this mechanism as effectively taxing “profits that never existed” when gains disappear after price reversals, characterising it as a “phantom tax” that forces asset disposal under adverse conditions .

To understand the practical dynamics, consider a two-year scenario involving a simple Bitcoin holding. Suppose an investor begins Year 1 with crypto worth €100 000. By the end of that calendar year, the asset appreciates to €120 000. The unrealised gain of €20 000 would be included in the investor’s Box 3 taxable income. After applying the tax-free allowance and allowable costs, a 36 % rate on that €20 000 gain could result in a sizeable cash tax obligation in early Year 2, depending on thresholds and netting rules.

If in Year 2 the market value falls to €90 000, the investor’s portfolio shrinks and the gain from Year 1 has largely evaporated. Nevertheless, the tax owed for Year 1 remains payable. While the regime allows losses to be carried forward once they exceed the statutory threshold, those losses do not erase the previous tax demand already paid on unrealised gains. This dynamic exposes holders to a liquidity mismatch: paying tax on “paper gains” that no longer exist in realisable form if the market declines, a point repeatedly raised by market participants as a central criticism .

Industry voices have articulated nuanced objections beyond this mechanical issue. A cybersecurity expert cited on CryptoSlate warned that annual taxation of unrealised gains could trigger forced liquidations, particularly in volatile markets. If asset holders lack available cash to satisfy tax liabilities, they may be compelled to sell at unfavourable prices, potentially precipitating downward price spirals that exacerbate broader market stress. Crypto leaders such as Balaji Srinivasan have expanded this critique, arguing that internal market dynamics could create a contagion effect, whereby forced sales in one jurisdiction depress prices more widely, eroding investment value and pushing capital toward jurisdictions with more favourable tax environments .

Beyond liquidity concerns, commentators have highlighted implications for long-term investor behaviour. The ethos of crypto investing has often emphasised holding through volatility to capture long-term growth. Critics argue that an annual tax on unrealised increases undermines this strategy by imposing cash tax obligations prior to any sale event. Opponents describe the policy as antithetical to the economic rationale for holding volatile digital assets over extended periods and warn that some investors may either relocate assets or change their domicile to avoid onerous tax burdens. Others contend that the tax disproportionately impacts middle-class investors and reduces incentives for wealth accumulation, a critique that resonates with broader debates on the fairness and neutrality of wealth taxes .

Some industry observers have even drawn historical comparisons, noting that past wealth or capital taxes levied without regard to liquidity have been associated with capital flight or entrepreneurial emigration. In the Dutch debate, critics have invoked these historical analogies to underscore the risk that high tax burdens on unrealised gains could lead to broader restructuring of investor behaviour and financial migration within the European Union .

The cumulative effect of these criticisms is to frame the reform not merely as a technical adjustment to Box 3 but as a potential structural pressure on the Dutch crypto market. For holders whose assets appreciate sharply one year and decline the next, the annual accrual model may create situations in which tax payments are owed on gains that have subsequently evaporated. This mismatch between valuation and liquidity is at the heart of the industry’s most salient objections to the proposed regime and shapes much of the market discourse surrounding the Netherlands’ tax overhaul .