The Dutch Box 3 Shift: Why Unrealized Gains Matter for Investors

The Dutch Box 3 Shift: Why Unrealized Gains Matter for Investors

The Dutch Box 3 Shift: Why Unrealized Gains Matter for Investors

The Netherlands is changing the way it taxes private wealth.

For many years, Dutch Box 3 taxed savings and investments using a notional return. The system did not look at the exact return a taxpayer made. It applied fixed percentages to categories of assets and then taxed the calculated income.

That system has been challenged repeatedly. The Dutch government is now moving toward a regime based on actual return. The important point for investors is simple:

Under the proposed new Box 3 system, many assets may be taxed annually on value increases, even if the asset has not been sold.

For people with substantial portfolios, private investment accounts, cryptocurrency, second homes, foreign assets, or internationally mobile family wealth, this is not a small administrative change. It is a liquidity, timing and relocation issue.

This article explains the problem, who is exposed, and how DriehuisGroup can help investors review their position before the rules become more difficult to manage.

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1. What is Box 3?

Dutch personal income tax is divided into boxes. Box 3 covers income from savings and investments. This can include:

  • bank accounts;
  • listed shares;
  • investment funds and ETFs;
  • bonds;
  • cryptocurrency;
  • second homes and other non-primary real estate;
  • foreign investment assets;
  • debts linked to Box 3 assets.

Box 3 does not generally apply to business income, employment income, or substantial shareholdings that fall into Box 1 or Box 2. For high net worth individuals, the exact box classification is critical.

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2. What is changing?

The Dutch government is aiming to introduce a new Box 3 system from 1 January 2028. The proposal is known as the Wet werkelijk rendement box 3: the Box 3 Actual Return Act.

The core idea is that Box 3 should tax the actual return from assets rather than a notional return.

Actual return can include two elements:

  1. Direct income

Short answer

This page matters because The Dutch Box 3 Shift: Why Unrealized Gains Matter for Investors is usually not solved by one form, one provider, or one meeting. The practical route works when the documents, timing, counterparties, and local execution are aligned before expensive mistakes appear.

Examples: interest, dividends, rent and other income received from assets.

  1. Value movement

Short answer

This page matters because The Dutch Box 3 Shift: Why Unrealized Gains Matter for Investors is usually not solved by one form, one provider, or one meeting. The practical route works when the documents, timing, counterparties, and local execution are aligned before expensive mistakes appear.

Examples: increases or decreases in the value of shares, crypto, funds, foreign currency positions or other assets.

The most important issue is the second element. For many assets, the proposal is based on capital growth taxation. That means the annual increase in value can be taxed even before a sale.

In other words, a portfolio may create a tax bill even if the investor has not realised cash.

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3. Unrealized gains: the real problem for investors

An unrealized gain is a paper gain.

Example:

  • You own a listed investment portfolio worth €2,000,000 on 1 January.
  • By 31 December, the portfolio is worth €2,300,000.
  • You did not sell the investments.
  • Your paper gain is €300,000.

Under a capital growth approach, that annual increase may be treated as taxable return. The investor may therefore need to pay tax without having received sale proceeds.

This creates several problems:

Liquidity pressure

If the portfolio increased in value but produced limited cash income, the investor may need to sell assets simply to pay tax.

Volatility risk

A portfolio can rise in one year and fall in the next. Annual taxation of value movements can create tax exposure before long-term gains are actually secured.

Cross-border mismatch

If another country taxes only realised gains, the investor may face timing mismatches. One country may tax a paper gain while another country recognises the gain only on sale.

Record-keeping burden

Investors will need stronger annual valuation records, acquisition records, evidence of costs where allowed, and documentation for foreign assets.

Relocation timing

People who are already planning to leave the Netherlands need to understand whether changing tax residence before or after key dates may materially affect their exposure.

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4. What happens before 2028?

Until the new legislation takes effect, the Dutch tax authorities continue to use the notional return system, unless a taxpayer’s actual return is lower. In that case, the actual return can be used under the rebuttal scheme.

For 2025 and later years, taxpayers can report actual return in the tax return where relevant. For earlier years, the specific actual-return form may apply.

This means investors should already be collecting data. Even before 2028, the direction is clear: Dutch wealth taxation is moving closer to actual annual economic performance.

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5. Who should review their position now?

A Box 3 review is especially relevant if you are:

  • a Dutch tax resident with a substantial investment portfolio;
  • a Dutch resident holding crypto assets;
  • an entrepreneur who has sold a business and now holds investment assets privately;
  • a family office or family with cross-border assets;
  • a person with a second home or foreign real estate;
  • a Dutch resident considering relocation;
  • a former resident with continuing Dutch exposure;
  • a foreign national living in the Netherlands temporarily;
  • an investor using foreign brokers, foreign bank accounts or non-euro positions.

The larger and more mobile the asset base, the more important planning becomes.

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6. Example: listed portfolio with no sale

A Dutch tax resident holds a listed securities portfolio.

  • Opening value: €1,500,000
  • Closing value: €1,850,000
  • Dividends received: €25,000
  • Sales during the year: none

The investor may think there is no taxable gain because nothing was sold.

Under a capital growth system, the tax analysis may be different. The annual increase of €350,000 may be relevant, together with the dividend income.

The problem is not that the portfolio performed well. The problem is that the tax may arrive before cash has been realised.

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7. Example: crypto investor

A Dutch resident owns crypto assets.

  • 1 January value: €600,000
  • 31 December value: €1,100,000
  • No sale
  • No cash income

The investor has a €500,000 unrealized increase. If that increase is taxed annually, the investor may need to liquidate part of the position to fund the tax.

Crypto volatility makes this especially sensitive. A taxpayer could face tax after a strong year and then see the value fall before assets are sold.

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8. Example: internationally mobile entrepreneur

An entrepreneur sells a company and moves the proceeds into private investments. The person is considering leaving the Netherlands within the next two years.

The key questions are:

  • Is the individual still Dutch tax resident?
  • Which assets are in Box 3, Box 2 or another category?
  • Is there an exit tax exposure?
  • Will the destination country tax future realised gains?
  • Is there a double tax treaty?
  • Should the portfolio be reorganised before relocation?
  • Should a company, holding or family structure be reviewed before departure?

This is not a question to answer after relocation. It should be modelled before decisions are made.

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9. What about people moving into the Netherlands?

The rules do not only matter for people leaving.

An investor moving into the Netherlands should understand the Box 3 system before arrival. A portfolio that is tax-efficient in another country may become inefficient once the person becomes Dutch tax resident.

Before moving, it is sensible to review:

  • asset classes;
  • embedded gains;
  • broker reports;
  • liquidity;
  • reporting obligations;
  • foreign tax credits;
  • treaty position;
  • whether a different EU base may be more suitable.

For internationally mobile families, relocation should be structured before tax residence changes, not after.

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10. What should investors do now?

The correct solution depends on the facts. However, serious investors should consider the following steps.

Step 1: Map the assets

Prepare a full overview of:

  • bank accounts;
  • brokers;
  • securities portfolios;
  • crypto wallets and exchanges;
  • private loans;
  • real estate;
  • foreign assets;
  • company interests;
  • pension and insurance products;
  • debts linked to investment assets.

Step 2: Identify the tax box

Not every asset belongs in Box 3. Some interests may fall into Box 2 or another regime. The classification can change the result completely.

Step 3: Model annual value movements

Investors should model what happens if annual value increases are taxed before sale.

Questions to answer:

  • How much tax could arise after a strong market year?
  • Is there enough cash to pay it?
  • Would assets need to be sold?
  • What happens if the portfolio falls the following year?

Step 4: Review residency

Tax residence is often the central issue. If a person’s life, home, family, business and economic interests remain in the Netherlands, leaving on paper will not solve the problem.

A real relocation must be credible, documented and practical.

Step 5: Consider a structured EU relocation

For some investors, entrepreneurs and families, Bulgaria may be a practical EU base. Bulgaria offers a European location, operational cost advantages and a business environment that can be suitable for entrepreneurs who need more than a passive address.

This must be done properly. A relocation strategy should include immigration, residence, company setup, banking, accounting, local substance and practical execution.

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11. How DriehuisGroup helps

DriehuisGroup supports serious investors, entrepreneurs and companies entering Bulgaria and the European market with structure, discretion and local execution.

For Dutch investors affected by Box 3 changes, we can coordinate a practical review covering:

  • personal relocation planning;
  • EU residency options through Bulgaria;
  • Bulgarian company setup and structuring;
  • coordination with tax lawyers and accountants;
  • review of investment and holding structure;
  • banking and accounting setup;
  • operational substance planning;
  • family relocation logistics;
  • practical implementation in Bulgaria.

We do not sell theory. We help clients move from analysis to execution.

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12. The key message

The Dutch Box 3 changes are not only a tax issue. They are a planning issue.

If your portfolio can be taxed on annual value increases before sale, you need to understand the cash-flow effect, the timing effect and the relocation effect.

For high net worth individuals, waiting until the law is fully operational may be too late. The right time to prepare is before tax residence, asset structure and documentation become harder to change.

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Private case review

If you are a Dutch resident, former Dutch resident, or internationally mobile investor with exposure to Box 3, DriehuisGroup can help you assess your options.

Typical first review topics:

  • Current country of residence
  • Dutch tax exposure
  • Portfolio size and asset classes
  • Planned relocation date
  • Family situation
  • Company interests
  • Desired EU base
  • Need for residence, company setup or operational substance in Bulgaria

Request a private Box 3 relocation review

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Important note

This article is general information only. It is not legal, tax or investment advice. Tax outcomes depend on personal facts, residence, asset classification, treaty position and future legislative developments. Always obtain qualified tax advice before making decisions.

Need structured support in Bulgaria?

DriehuisGroup helps foreign entrepreneurs, investors, companies, and private clients coordinate practical Bulgaria routes with clearer sequencing, cleaner documents, and stronger local execution.

Contact DriehuisGroup

Disclaimer

This article is for general informational and marketing purposes only and does not replace professional advice for your specific case.