Box 3 2026 — what expats in the Netherlands need to know

First published June 2026 · updated October 2026 · 8 min read

If you keep savings or investments in the Netherlands, you pay 36% tax on a deemed return every year — an assumed figure, not what you actually earned. This is Box 3, the Dutch wealth tax system, and it works very differently from the way investment income is taxed in Ireland or the UK.

How does Box 3 work?

Currently, the Dutch tax authority does not tax your actual investment returns. Instead, it uses a "deemed return" — a fixed assumed percentage applied to your wealth — and taxes that. The deemed return differs depending on what you hold. In 2026, the rate for investments and other assets is 6%. The rate for savings (bank deposits) is set at approximately 1.28% for 2026 (preliminary — the definitive savings rate is only confirmed in early 2027 once actual market rates for the full year are known). Both are taxed at 36%.^[1]

So if you hold €100,000 in investments on top of the tax-free allowance (more on that below), the tax authority assumes you earned €6,000 from it and charges 36% of that — €2,160 — regardless of whether your portfolio actually went up, down or sideways.

How much is tax-free in 2026?

There is a tax-free threshold of €59,357 per person in 2026 (€118,714 for couples with a fiscal partner). Assets below this threshold are not subject to Box 3 tax at all. This is called the heffingsvrij vermogen. The threshold applies to your total Box 3 wealth — across all accounts and asset types combined, not per account.^[1]

What about debts?

Debts can reduce your Box 3 wealth, but two things matter. First, there is a threshold (drempel): only debt above €3,800 per person (€7,600 for fiscal partners) counts, and the part above it carries its own deemed rate — provisionally 2.70% for 2026.^[1][2] Second, the mortgage on your main home is not a Box 3 debt at all. Your own home and its mortgage are taxed separately, in Box 1, not here. Only debts outside that — a consumer loan, or a mortgage on a second property — go into Box 3.^[2]

Work out your own Box 3 tax

The official method has several steps, so rather than walk through a static example, here is a calculator that does it for you. Change your situation, your investments and your savings (and a debt, if you have one) and it shows the full breakdown, step by step, with the Dutch terms the tax office uses.

This is the standard method. The two sections that follow — the counter-evidence rule and the year-end question — are the main exceptions to it.

What if your actual return was lower?

Since July 2025, there is a formal route to pay less. Under the tegenbewijsregeling (counter-evidence rule) you can declare your actual return, and the Belastingdienst then taxes whichever is lower: the deemed return or your actual one. Claiming never costs you more — if your actual return turns out higher, the deemed figure stands.^[7]

The comparison is not “my return against 6%”, though. The tax-free allowance (€59,357 for a single person) only applies to the deemed calculation. Your actual return is counted on all your wealth, from the first euro, and costs cannot be deducted (interest on Box 3 debts is the exception).^[7] So what you compare is your actual return in euros against your Box 3 income from the deemed calculation — the voordeel uit sparen en beleggen, with the allowance already taken off.

A rule of thumb. Take €80,000 invested, single. Only €20,643 sits above the allowance, so the deemed return is €20,643 × 6% = €1,239. Spread over the full €80,000, that is about 1.5%. Your actual return has to come in below that — not below 6% — before claiming helps. The larger your wealth, the less the allowance matters and the closer the break-even gets to 6%. For fiscal partners the comparison is made for the two of you together, against the combined €118,714 allowance, so the same break-even applies at double the wealth.^[1]

Treat this as a guide only. It assumes everything is invested and there are no debts. Savings pull the break-even down sharply — €100,000 held entirely in savings, single, breaks even at about 0.5% — and debts move it too. The calculator above shows the break-even for your own mix.

It is a decision you make after the year has ended, when you file your return and the actual figure is known.^[7] What it takes is careful record-keeping: interest, dividends, rent, and realised and unrealised changes in value.

Can you just park it all in savings on 1 January?

A tempting idea: shift everything out of investments into a deposit account just before 1 January — the snapshot date the tax is measured on — so it is taxed at the low savings rate, then move it straight back afterwards. It does not work. There is an anti-arbitrage rule (peildatumarbitrage): if you switch money between categories within the three months around the snapshot date and reverse it, purely to lower the tax, the Belastingdienst disregards the move and taxes you as though you had never made it. The annual return (aangifte) even asks you directly whether you made transactions like this around the snapshot date.^[3]

Foreign assets: is property abroad taxed in the Netherlands?

As a Dutch resident you declare your worldwide assets, so foreign bank accounts and foreign investments fall into Box 3 exactly like Dutch ones. Foreign property is an exception: a holiday home or rental abroad is still declared in Box 3, but tax treaties generally give the taxing rights to the country where the property sits, and the Netherlands then grants relief to avoid double taxation. The practical result is that you usually pay little or no Dutch Box 3 tax on the property's value — but the relief is calculated proportionally and is not always a complete offset, and the exact outcome depends on the specific treaty with that country. Worth getting checked rather than assumed.^[4]

The 30% ruling change

Until the end of 2024, expats with the 30% ruling could elect partial non-resident status, which kept foreign assets out of Box 3. That option was abolished from 1 January 2025.^[5] There is transitional relief, and which side of it you fall on depends on when your ruling started: if you were already using the 30% ruling before 2024, you can keep electing partial status until the end of 2026. But if your ruling started from January 2024 onwards, the option is already gone — from 2025 you must declare your worldwide Box 3 assets, including UK ISAs, foreign savings accounts and overseas investment portfolios.^[5]

For what the ruling itself is worth, and what changes when it ends, see The 30% ruling — what it’s worth, and what you lose when it ends.

A UK ISA has no special status in the Netherlands. It falls within Box 3 and is taxed like any other investment account.

Changes ahead

Box 3 is under active revision. The plan to replace the deemed-return system with a tax on actual returns from 2028 passed the Tweede Kamer (lower house) in February 2026, but the Eerste Kamer (senate) has not yet voted on it, and the cabinet has since put forward further proposals — both for 2027, within the current system, and for the shape of the 2028 regime. These are now going through parliament.^[6] Nothing is decided yet, and the figures in this article are the 2026 rules. A separate article on the proposals, and what they would mean in practice, will follow once there is a bill before the Tweede Kamer.