Box 3: the Dutch tax on savings for Americans

Once you live in the Netherlands, your US brokerage account, your savings and even your rental condo back home can land in Box 3, a tax on an assumed return that the Dutch Supreme Court has spent five years picking apart.

The short version

Box 3 taxes a deemed return on your net assets on January 1, not your actual dividends and gains [1].
For 2026, the deemed returns are 1.28% on bank balances (provisional), 6.00% on investments and other assets, and 2.70% on debts (provisional), taxed at 36% [1].
The first EUR 59,357 (about USD 66,300) per person is tax-free in 2026, or EUR 118,714 (about USD 132,500) for a couple [1].
If your actual return was lower, you can now report it and pay tax on that instead, thanks to Supreme Court rulings in 2021 and 2024 [2][3].
An actual-return system is planned from 2028. The lower house has passed the bill, but the Senate still has to vote [4].

USD conversions in this guide use the Federal Reserve H.10 rate of October 30, 2026 (USD 1.1163 per euro).

What Box 3 is

Dutch income tax splits your income into three "boxes." Box 1 is work and your home, Box 2 is a substantial stake in a company, and Box 3 is savings and investments (sparen en beleggen). There's no US equivalent. Back home, the IRS taxes interest, dividends and capital gains when you actually receive them. The Netherlands, for decades, has taxed what it assumes your wealth earned.

Box 3 applies to Dutch tax residents on their worldwide assets. That includes things Americans often forget:

US checking and savings accounts
US brokerage accounts, ETFs, mutual funds and individual stocks
Crypto
A rental property or vacation home in the States, or a second home in the Netherlands
Money other people owe you

Your own main home is taxed in Box 1, not Box 3 [4]. US retirement accounts such as 401(k)s and IRAs raise their own questions under the Dutch rules and the US–Netherlands tax treaty. A tax adviser who knows both systems can check how yours are treated.

How the 2026 calculation works

The Belastingdienst calculates the provisional 2026 assessment using the Overbruggingswetgeving, the bridging law adopted after the courts struck down the old system. It looks at what you actually held on January 1, 2026, split into three categories [1]:

Category (2026)	Deemed return	Status
Bank balances	1.28%	Provisional, finalized early 2027
Investments and other assets	6.00%	Fixed
Debts (above the EUR 3,800 threshold per person)	2.70%	Provisional, finalized early 2027

Then [1]:

Work out the deemed return on each category and add them up, subtracting the deemed cost of your debts.
Work out your net assets (assets minus debts above the threshold).
Subtract the tax-free allowance of EUR 59,357 per person.
Take your share of what's left as a percentage of the net assets.
Apply that share to the deemed return. That's your Box 3 income.
Multiply by 36%.

The Belastingdienst's own example: a single person with EUR 150,000 (about USD 167,400) in savings and nothing else owes about EUR 417 (about USD 465) in Box 3 tax for 2026. A couple with the same savings owes about EUR 72 (about USD 80) each, because each partner gets an allowance [1].

The picture changes fast with investments. At a 6% deemed return, a EUR 300,000 (about USD 334,900) brokerage account is assumed to earn EUR 18,000 (about USD 20,100) a year before the allowance, whether the market went up, sideways or down.

The court fights: 2021, 2024 and 2026

This is the part that explains why the system keeps changing.

Date	What happened
December 24, 2021	The Supreme Court (Hoge Raad) rules in the "Christmas ruling" (Kerstarrest) that the old Box 3, which assumed a fixed mix of savings and investments, discriminates against people whose real return was lower [2].
From 2021	The bridging law uses your actual mix of savings and investments, with deemed returns closer to reality [2].
2024	The Supreme Court rules that the new deemed returns still discriminate if your actual return was lower, so taxpayers must be able to show their real return [2].
July 1, 2025	The Wet tegenbewijsregeling box 3 (counter-evidence law) lets taxpayers claim back tax using the form Opgaaf werkelijk rendement [2].
June 25, 2026	The Supreme Court rules that people who didn't file an objection for 2017–2020 have no right to a refund for those years [3].
July 17, 2026	The Belastingdienst adopts that ruling in a collective decision [3].

What that means for you today:

For 2021 through 2024, anyone with Box 3 income can file the Opgaaf werkelijk rendement form, even without a letter from the tax office [3].
For 2025, you report your actual return directly in your income tax return. If your assets are above the tax-free allowance, the return asks whether you want to. It's optional, and the Belastingdienst uses whichever calculation is better for you [5].
For 2026, your provisional assessment uses the deemed returns above. If your actual return turns out lower, the tax office adjusts your Box 3 income when you file your 2026 return [1].

"Actual return" here means interest, dividends and rent plus changes in value, minus costs, so a strong year on Wall Street won't help you. It helps most in years when markets fell or when your money sat in low-interest savings.

The planned actual-return system from 2028

The government's plan is a new Box 3 that taxes your real return each year [4]:

Interest, dividends and rent are taxed as received.
Stocks and similar assets are taxed on their change in value each year, even if you don't sell. The Dutch call this a vermogensaanwasbelasting. Losses can be offset against later gains.
Real estate other than your main home, and shares in qualifying startups and scale-ups, would be taxed on gains only when you sell.
Costs such as interest paid and transaction costs would be deductible.

The Wet werkelijk rendement box 3 passed the lower house (Tweede Kamer), but the Senate (Eerste Kamer) still has to deal with it. The government aims for January 1, 2028, and the bill must take effect by January 1, 2029 at the latest [4]. Until it's law, treat the details as proposed.

What Box 3 means for Americans

Here's the awkward part. Box 3 and the US tax system don't line up.

Timing mismatch. The Netherlands taxes a deemed or annual return. The US taxes realized gains and actual income. You can pay Dutch tax on a paper gain this year and US tax on the actual gain years later.
Foreign tax credit questions. Whether Box 3 tax counts as a creditable foreign income tax against your US tax, and on which income, is a technical question. A US expat tax preparer can check your situation.
Partial non-resident status is ending. Americans on the 30% ruling used to elect out of Box 3. That choice is gone from the 2025 return, except for those who used the ruling before 2024, who can keep it through the 2026 return [6]. See our 30% ruling guide.
Dutch funds and PFICs. If you invest locally to keep things simple in Box 3, be careful: Dutch and other non-US mutual funds and ETFs are usually PFICs for US tax purposes, with punishing rules.
Reporting doesn't change. Your Dutch accounts still count toward the FBAR once the total tops USD 10,000 at any time in the year. Living abroad, Form 8938 applies above USD 200,000 at year-end or USD 300,000 at any time for single filers, and USD 400,000 or USD 600,000 for joint filers [7].

Want to compare notes on how others handle a US brokerage account under Box 3? Ask in our community group for Americans in the Netherlands.

Box 3 for Americans: how the Dutch tax your savings, the court fights and the 2028 overhaul