Why do the portfolios use index funds rather than ETFs?

Index funds and ETFs: the same on the inside, different on the outside

First, it's important to understand that index funds and ETFs are essentially the same thing on the inside. Both are funds that passively track a market index. The difference is purely in the "wrapper", meaning how they're structured and traded:

• Index funds are bought and sold directly through the fund provider, typically once per day at the closing price
• ETFs (Exchange-Traded Funds) are traded on stock exchanges throughout the day, like individual stocks

Both give you the same diversified, low-cost index investing strategy. The real difference that matters for Belgian investors is how they're taxed.

Why Curvo uses index funds: it's about taxes

The main reason is taxes. All ETFs are subject to the transaction tax ("taxe sur les opérations boursières" or "beurstaks" or TOB). This tax must be paid at every purchase and sale. Depending on the type of the ETF and its country of registration, the rate varies between 0.12% and 1.32% of the transaction value.

In contrast with ETFs, certain index funds are exempt from the transaction tax. For this reason, all Curvo portfolios are made up of index funds for which no transaction tax needs to be paid.

Updated on: 29/10/2025