7 things eating into your Dutch investments (and how to avoid them)

Between the taxman, brokerage fees, and currency conversion costs, your investments can end up taking quite the hit. Let’s fix that.

Here are seven of the most common culprits whittling away at your Dutch investments, and what you can actually do to mitigate the effects of each.

1. Box 3 taxes your estimated gains, not your actual earnings

In the Netherlands, the tax you pay on investments, known as Box 3 taxes or vermogensrendementsheffing (capital gains tax), has precious little to do with your actual earnings. Instead, the Belastingdienst takes a slice of your estimated gains.

In other words, you’re taxed on earnings the tax office assumes you’ve made, irrespective of whether you’ve actually gained that value through your investments.

For 2026, the Belastingdienst assumes a flat 5.88% return on investments like shares, ETFs, and bonds, then charges a 36% tax on that figure.

Have you made less than 5.88% on your investments? Doesn’t matter. Have you lost money entirely? Still doesn’t matter. To the tax office, you’re taxed as if you’ve hit that 5.88% regardless.

So, what can you do about it? Well, your first port of call is making sure you’re claiming your full tax-free allowance.

In 2026, the Belastingdienst sets this at €59,357 per person (or €118,714 with a tax partner). Anything below this value is tax-free, and you can deduct this value from your taxable return.

Meanwhile, if your actual returns are lower than the assumed 5.88%, a handy little scheme called the Wet tegenbewijsregeling box 3 (Box 3 counter-evidence act) has your back.

Just report your actual returns on your income tax return, and the Belastingdienst will use the more accurate figure instead.

2. Currency conversion costs chip away at non-euro purchases

Many of the most popular ETFs and shares trade in US dollars, not euros. This means that every time you purchase non-euro investments, your broker needs to convert your money into USD — pocketing a currency conversion fee for the trouble.

While FX or foreign exchange fees might seem like small fry, they definitely add up over time. Thankfully, there are two main ways to keep them in check.

Before you sign up anywhere, check, double-check, and triple-check your broker’s FX or auto-conversion fees. These can vary more than you’d expect, and percentages will add up the more you trade.

And, where it suits your investment strategy, try leaning towards EU-listed ETFs and euro-priced shares.

3. Investment platforms can charge you just for making an account

Currency conversions aren’t the only fees hitting your account, because some brokers can hit you with charges before you’ve even bought a single share.

These are called “custody” or “platform” fees, and they’re a monthly or yearly charge that brokers levy for keeping your account open.

Prices vary per platform, but they’re typically a flat fee of several euros or a percentage of your total portfolio.

While “several euros” sounds relatively harmless, these have a nasty way of compounding in the long run. Within a few years, they could easily skim hundreds of euros off your returns — and that’s before we’ve even hit transaction fees.

If you want to avoid the steepest platform fees, check two things before you open an account:

• Does the broker charge an account fee? Many don’t.
• If they do charge an account fee, is it a flat fee or a percentage of your portfolio? If it’s the latter, the value of that percentage fee grows as your investments do. For anything but the smallest of portfolios, a flat fee usually works out cheaper in the long run.

4. Panic selling in a downturn might add to your losses

If you thought fees and taxes were the only things whittling away at your investments, helaas… you’re (probably) to blame, too.

When the market drops, many investors scurry to jump ship and sell their stocks before the downturn gets worse.

However, the problem with selling during a downturn is that you miss the market’s inevitable rebound, thus compounding your losses.

Needless to say, the fix is mostly mental. While every fibre of your being might be screaming at you to sell, it’s helpful to treat downturns as a normal part of investing, as opposed to a financial nightmare.

And, if you haven’t already, consider opening a separate emergency fund for savings that can cover your expenses in a pinch. That way, when life throws you a financial curveball, you aren’t forced to sell your investments to cover your bills.

5. Broker fees are charged on each trade you make

Beyond any account fee, plenty of brokers pocket small charges on transactions you make.

These can range from a commission every time you make a trade, a transfer fee if you move your investments elsewhere, or even an inactivity fee if you forget to log in for a while.

While these small charges are easy to miss on their own, they can certainly stack up over a few years of trading, taking an unwelcome chunk out of your investments.

Where you can, opt for brokers that offer commission-free trading or a core selection of low-cost funds.

And we hate to state the obvious, but always make sure to read the fine print before you start trading, especially when it comes to brokerage fees.

6. Inflation will quietly erode your uninvested funds

Waiting for the “perfect” moment to buy stock is a very natural urge, because we’re all hoping to get the most bang for our buck.

The downside, however, is that while your money sits in a low-interest Dutch savings account, inflation is busy chipping away at what your funds are actually worth.

In the investing world, this is known as “cash drag”: the opportunity cost of holding uninvested cash, instead of investing it in higher-yield assets. 

The good news is that there are some easy fixes, with relatively minimal risk. One option is to move your funds into a money market account until you’re ready to invest.

A money market account is a type of deposit account offered by banks and credit unions, which typically offers much higher variable interest rates than standard savings accounts. (The trade-off, however, is that these typically require higher minimum balances.)

If a money market account isn’t your scene, it’s worth checking whether your investment platform pays interest on uninvested cash. Some offer regular interest on cash in your account, often at higher rates than traditional banks.

7. Chasing last year’s winners will have you buying at peak price

Everyone loves jumping on the hype train, and investors are no different.

But while it’s tempting to hop on whichever stock was hot property last year, strong past performance isn’t always the best predictor of future returns.

There’s even a name for what often happens next: mean reversion. This financial theory states that asset prices eventually return to their long-term average, even if they’ve currently soared or plummeted.

And if you’re buying assets at the peak of their popularity, you’re likely facing the steepest prices for investments that likely won’t hold that value long-term.

The more sensible approach is to choose a broad, diversified portfolio, as opposed to betting on individual winners. Your risk is then spread over a wide range of investments, and you needn’t pay top dollar (or euro!) for diminishing returns.

What are some handy investment tips you’ve learnt over the years? Share them in the comments below.