Box 3: Savings and Investments Tax for Expats

Box 3 has been a moving target since the Hoge Raad ruled in 2021 that the old deemed-return system was inconsistent with the European Convention on Human Rights for taxpayers whose actual return was significantly lower. The Dutch government has been in a transitional regime since then, and a permanent werkelijk-rendement (real-return) system is scheduled to take over from 1 January 2027. For expats, this means two things: get the current rules right, and prepare for the change. This page covers both.

At a glance — key facts

  • Box 3 taxes savings and investments above the heffingsvrij vermogen.
  • Tax-free threshold 2026: roughly €59,357 per person (double for fiscal partners).
  • Tax is on a deemed return, not the real return, under transitional rules.
  • Deemed-return percentages differ between cash, other assets and debts.
  • Headline Box 3 rate in 2026: 36% on the deemed return.
  • Werkelijk-rendement (real-return) system scheduled to start 1 January 2027.

How Box 3 works in 2026

The 2026 Box 3 system uses a deemed return split by asset class:

– Cash and savings. Deemed return based on actual market savings rates (currently around 1.5-2%).
– Other assets. ETFs, stocks, second properties, crypto, gold — deemed return around 6%.
– Debts. Deduct a deemed cost of around 2.5%.

The deemed return on your total Box 3 base (assets minus debts, minus the heffingsvrij vermogen) is taxed at 36% in 2026.

For most expats with a brokerage account and some cash savings, the effective Box 3 tax works out at roughly 1.5-2% per year of total Box 3 assets. A portfolio of €200,000 in ETFs and €30,000 in cash gives a Box 3 bill of roughly €3,500-€4,000.

If your actual return is lower than the deemed return, you can elect to be taxed on actual return under the tegenbewijsregeling. Keep records.

What changes in 2027

The werkelijk-rendement (real-return) system replaces the deemed-return regime from 1 January 2027. The headline change:

1. Tax is on actual return. Interest, dividends, rental income, realised capital gains.
2. Unrealised capital gains on liquid assets (listed shares, ETFs) are also taxed on a vermogensaanwasbelasting basis — the increase in market value over the year, whether or not you sell.
3. Unrealised gains on illiquid assets (second properties, private company stakes) are taxed on realisation.
4. Losses can be carried forward to offset future gains.
5. The heffingsvrij vermogen is retained, although the exact threshold may change.

The reform will produce winners and losers. Expats with high actual returns on a large ETF portfolio will likely pay more under werkelijk-rendement. Those holding mostly cash at modest interest will pay less. Run your specific numbers before the switch.

Common Box 3 mistakes for expats

The most expensive Box 3 mistakes expats make:

– Forgetting foreign accounts. Since 2025, the partial non-resident election is gone. Your foreign brokerage, foreign savings, and home-country pension lump sums that you keep liquid all count toward Box 3. Many expats only declare Dutch accounts and run into an audit correction one to two years later.
– Wrong asset classification. Crypto and gold are other assets with a 6% deemed return, not cash. ETFs are other assets. A second property is other assets — even if you keep it in your country of origin. Mortgage debt on a foreign second property is a Box 3 deduction.
– Missing the tegenbewijs option. If your actual return is materially lower than the deemed return (a fixed-income portfolio in a low-rate environment, for example), the tegenbewijsregeling can save real tax. Most filers default to the deemed-return number without checking.
– Misreading the heffingsvrij vermogen for partners. Couples get roughly €118,714 combined — but only if both partners declare as fiscal partners on the return. Filing separately wastes one allowance.


Above the heffingsvrij vermogen?

Have a portfolio above the heffingsvrij vermogen or assets abroad? Book a free 30-minute call to model your Box 3.

Model my Box 3 →


Frequently asked questions

Yes, since the partial non-resident election ended in 2025. As a Dutch tax resident, you declare worldwide Box 3 assets. Tax treaty rules may give relief on specific assets but the default is full Dutch declaration.

A tax-free wealth threshold. In 2026 it is roughly €59,357 per person — meaning a couple has roughly €118,714 of Box 3 base before any tax is due.

Your primary residence is in Box 1, not Box 3. A second property or a property you rent out is in Box 3.

ETF holders with high actual returns will likely pay more, because unrealised gains are taxed annually as they accrue rather than on sale. The exact impact depends on portfolio composition and return history.

Yes, if it relates to a Box 3 asset (a second property or investment property). The deemed-cost percentage applies. A mortgage on your primary residence stays in Box 1.


Related guides

Reviewed by Joan Ottenheim, CFP & FFP — last reviewed 2026-06-03.