Blog > Dutch Box 3 changes. What do you need to know about your investments.

Dutch Box 3 changes. What do you need to know about your investments.

For most people living in the Netherlands, Box 3 is a term that you hear a lot in the news but what is it exactly? And more importantly why do you need to worry about the upcoming changes. In short box 3 applies to your worldwide savings and investments. Over the last years, it has been messy, with legal battles between investors and the Belastingdienst. If you have significant savings or an investment portfolio, you need to be preperared of the changes to your situation.
Dutch Box 3 changes. What do you need to know about your investments.
Taxes: Dutch Box 3 changes. What do you need to know about your investments.
 3/12/2026   By Maurits, Team Expat Guide    Taxes

Dutch Box 3 changes. What do you need to know about your investments.

Box 3 - Why it didn't work

Until recently, the Dutch Tax Authority (Belastingdienst) taxed your wealth based on fictional returns. Regardless if you actually earned anything on your stocks or savings. They simply assumed you earned a certain percentage because you normally did in the past by getting interest and dividends.

This worked reasonably well until interest rates went to 0%. Savers were being taxed on assumed 4% returns while their bank was paying them 0% interest rate.
In late 2021, the Dutch Supreme Court (Hoge Raad) finally declared this system unlawful, ruling that it violated fundamental rights when the assumed return was higher than the actual return. This triggered a period of legislative chaos.

 

Where are we now

After the decision of the Dutch Supreme Court the goverment thought it was time for a different system. This is how it works now: 
The Belastingdienst still uses assumed returns, but they are segmented more realistically:

But when your actual total investment return is lower than the total assumed return the Belastingdienst calculates, you can now object. This is the direct result of the Supreme Court rulings.

You must be able to prove that your actual income (dividends, interest, rent) plus your realized and unrealized capital gains (price increases of stocks or property, minus value decreases) was lower than their assumed number. If you can prove it, your Box 3 tax bill will be recalculated based on your lower actual return. A fair system people believe but this is changing now. 


Box 3 - The new proposal


Capital Growth Tax
This applies to your stocks, bonds, bank deposits and cryptocurrencies.

Each year, you will be taxed on the actual income received (interest, dividends) plus the change in value of your portfolio between January 1 and December 31.
This means you will pay tax on unrealized gains. If your portfolio goes up by €10,000 "on paper" but you don't sell any shares, you still owe Dutch tax on that €10,000 growth that year.

Capital Gains Tax
This applies to your real estate (secondary properties/holiday homes) and shares in qualifying startups.
You are taxed on actual rental income annually, but the increase in the property's value is taxed only when you sell it (realized gains). This is much closer to what many people consider a standard capital gains tax.

No more Tax-Free Allowance
The current system allows a tax-free threshold of wealth (around €51,000 per person in 2026). The new system is expected to replace this with a tax-free annual return of €1,800. If your total actual return from all assets is less than €1,800, you don't pay any Box 3 taxes.

Losses
If you have a net loss in Box 3 in a given year, you will be able to carry that loss forward to offset future positive results, with no time limit. 

What does this mean for you as an expat

Taxing actual returns and unrealized gains on investments from 2028 will fundamentally change how you need to structure your assets.
Tt is important to note that these rules are not yet final. They face a lot of crisitism from experts and the public. The Dutch government is still working on the legislation and details may change before the system is introduced. But the tweede kamer agreed on it, so be prepared for the worst.

Liquidity problems

Under the proposed system, you may have to pay tax on unrealized gains which means increases in the value of your investments that you have not yet sold. If your stock portfolio grows significantly in value during the year but you do not sell any shares, you could still face a Dutch tax bill. Because you have not actually received cash from the investment, you may need to sell part of your portfolio simply to pay the tax, which could interfere with long-term investment strategies.


Partial foreign tax liability

With the 30% ruling, you could (until 2025/2026) make use of partial foreign tax liability. This meant that you do not have to declare your foreign assets in the Netherlands, which saves on administration and prevents double taxation. Property in the Netherlands was excluded. This advantage is now gone.

Strategy Realignment

The new rules force you to rethink how to allocate assets.

You will need to balance the advantages and disadvantages of different asset classes:

Liquid assets such as stocks and ETFs may face annual taxation on unrealized gains.
Illiquid assets such as real estate may still allow taxation to be deferred until the asset is sold, depending on the final legislation.

This shift could influence how you structure your long-term portfolios. Do you want to learn more, consult a Dutch Tax Advisor. 


The good news, it is not final yet. We will keep you posted!