Abstract
Anyone buying crypto in Belgium or the Netherlands sees one number: the fee. That number rarely tells the whole story. Besides the visible fee you pay a margin inside the price, possibly a surcharge on your payment method, and later withdrawal costs when you move coins to your own wallet. In this note we add those up into a single figure: the total cost of a purchase.
We did that across five trading days at eight platforms active in the Benelux, using three amounts and two coins. The result: the cheapest route costs about 0.30% of your money, the most expensive nearly 2%. On a single thousand-euro purchase that gap looks small. Under monthly investing over ten years it grows into several hundred euro, money that is not in your position and therefore never compounds.
The key conclusion is not which platform wins, but which choices inside a platform make the difference: the interface used, the payment method, the order type and how often you withdraw. Set those four dials well and you pay a fraction of the default at nearly any provider.
Key findings
- The gap between the cheapest and most expensive route is roughly twenty euro on 1,000 euro, or 2% of the amount invested.
- At six of eight platforms the spread exceeds the visible fee for amounts below 250 euro.
- The pro interface of the same platform is on average 78% cheaper than the simple buy button.
Fee plus spread plus payment surcharge, measured across five trading days. The pro interface with a limit order is the cheapest route in the test.
Why the visible fee misleads
Platforms advertise a per-transaction fee but also apply a margin in the price you receive. That margin appears nowhere in the confirmation and therefore does not show up as a cost in your annual statement. All you see is that a thousand euro bought slightly less bitcoin than the market price suggested.
Investing 100 euro monthly through a simple buy button costs about 239 euro over ten years at 1.99%. Through the pro interface of the same platform it is around 36 euro. That gap of over two hundred euro is not a theoretical exercise: it is money that never enters the position and therefore never rises with it.
Comparisons that line up fees alone therefore distort the picture. A platform with a 0.25% fee and a 0.9% spread is more expensive than one with a 0.4% fee and a 0.1% spread, even though the first looks cheaper in every advert.
- Fee: the percentage explicitly shown on your confirmation
- Spread: the difference between your price and the mid-market price
- Surcharge: extra cost for the chosen payment method
- Withdrawal: the fixed or variable cost of sending coins out
How a spread arises
An order book holds buy and sell orders side by side. The best bid and best ask rarely sit at the same price; the difference is the market spread. On bitcoin at a large European venue that is often less than a hundredth of a percent. Anything you pay above that is not market reality but a platform choice.
With a simple buy button you are not buying from the order book but from the platform itself. The platform takes a position, hedges it and charges a margin for that risk and for the convenience. The construction is legitimate, but it is expensive and rarely explicit.
On Sunday evenings, when liquidity is thin, we saw spreads two to four times wider than on an ordinary Thursday afternoon. The moment you buy is therefore a genuine cost item, especially on smaller coins.
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