Understand · ETF
The honest answer to the question your bank doesn't want you to ask.
Unfamiliar with some terms? Check the glossary →
An ETF (Exchange Traded Fund) is an investment fund that automatically replicates a stock market index — for example, the 1,400 largest global companies.
Concretely, buying a share of IMIE means buying a fraction of Apple, Microsoft, Nestlé, Samsung, Toyota and 8,999 other companies in a single transaction. Your capital is instantly diversified on a global scale.
Two characteristics distinguish ETFs from traditional funds:
Instead of betting on a single company, an ETF allows you to own a fraction of hundreds or thousands of companies simultaneously. If one company goes bankrupt, the impact on your portfolio is negligible.
Simulation — €300 / month for 30 years
Index ETF
IMIE · ~8% gross · TER 0.17%
~€408,000
Bank Active Fund
~8% gross · TER 1.73%
~€296,000
Difference · fees only
+€112,000
Indicative simulation before taxation. Identical gross rate — only fees differ.
It's not a question of the manager's talent. It's a mathematical question. Over 30 years, every euro taken in fees is a euro that no longer compounds. The effect is exponential: fees don't just reduce your return by 1.5% — they reduce your final capital by 25 to 35%.
Traditional banking funds often charge between 1.5% and 2.5% in annual fees. An ETF like those recommended here costs between 0.07% and 0.20% per year. Over 30 years, this difference in fees can represent more than 30% of your final capital.
Management fees are the only variable you can control with certainty. Predicting the future of the market is impossible; reducing your costs is a guaranteed return.
The practical conclusion: paying 1.5% in additional fees for active management is paying for a promise that statistics prove is rarely kept over the long term.
Classic savings products suffer from three structural handicaps compared to ETFs:
Handicap 1
Silent inflation
A savings account at 2.5% in a 2% inflation environment earns you 0.5% real. Your purchasing power stagnates. Over 20 years, your capital does not double — it loses value in real terms as soon as inflation exceeds your return.
Handicap 2
Punitive taxation
Interest from savings bonds and term accounts is taxed at 30% from the first cent. A gross rate of 3.10% becomes 2.17% net. Accumulating ETFs, on the other hand, generate no taxable income until you sell — gains compound freely for decades.
Handicap 3
The structural ceiling
A savings account cannot make you rich. Its return is capped by ECB policy rates, redistributed with a generous margin for the bank. In 2015, the best savings accounts earned 0.50%. In 2022, some fell to 0.01%. A global ETF follows global economic growth — a structurally more powerful engine.
That would be false. Banking products have their place — but a precise and limited place.
A savings account is irreplaceable for your emergency fund: 3 to 6 months of expenses, available immediately, without risk of capital loss. This is its legitimate function.
Beyond this security reserve, every euro left indefinitely in a savings account is a euro that underperforms.
« The question is not 'savings or investment?' It's 'what part of my savings needs to be liquid and risk-free?' »
Belgium presents a particularly unfavourable combination for the passive saver:
When you buy a share of IMIE, you become the owner of a fraction of 9,000 companies. Factories, patents, brands, logistics networks. These assets produce goods and services every day. A portion of these profits comes back to you, automatically reinvested. This is not speculation. It is the capture of human economic activity.
Three factors explain the long-term rise.
Global economic growth
Global economic growth
More people, more productive. Every year, innovations allow us to produce more with less. The global economy has grown by 3 to 4% per year on average for a century. The ETF merely reflects this expansion.
Inflation
Inflation
Your baker sells bread more expensively every decade. Listed companies do the same. Inflation erodes your savings, but it mechanically increases the revenues of the companies you own.
Reinvestment of profits
Reinvestment of profits
A company that earns 100 does not distribute everything. It builds a factory, develops software, buys a competitor. This reinvestment generates additional profits the following year. You are not only compounding your own contributions. The companies compound internally.
Add to this that the index cleans itself automatically: Kodak disappears, Apple emerges. No human manager, no emotion, no bias.
A simple analogy. Imagine owning 0.00000001% of every bakery, every port, every power plant, every laboratory, and every data center on the planet. As long as humanity bakes bread, transports goods, produces energy, and develops software, your slice of the cake grows.
This is not a prediction. It is the mechanism that took the MSCI World index from 100 points in 1969 to over 3,600 today.
"If the economy grows at 3%, why does the ETF return 8%?"
The question is legitimate. The answer comes down to three points.
You are not buying "the economy", you are buying listed companies. The 9,000 companies in the index are more profitable than average. They capture a growing share of global activity. Their profits grow faster than GDP, historically around 5% per year. Add 2% inflation passed through in prices and 1 to 2% dividends, and you get 7 to 9% total return. This is not an anomaly. It is the difference between owning the corner bakery and owning Nestlé.
Markets do not "have to" stagnate for the economy to catch up. Valuations fluctuate, sometimes too high, sometimes too low, but no mechanism forces stocks to stop. An ETF bought expensively will take longer to deliver its returns, but economic activity continues. No 20-year period has ever produced a negative return for a diversified global portfolio.
If growth stops permanently, your savings account won't save you. A catastrophe that kills capitalism also kills the banking system. Conversely, the crises that capitalism survives are precisely those where guaranteed products underperform the most. Your emergency fund in a savings account is essential. Your 20-year capital is better served by the productive diversity of the entire planet.
The real difference? €300 per month for 30 years in a savings account leaves you with about €148,000. In a world ETF, about €408,000. It's not a question of a few percentage points. It's €260,000 difference.
The only requirement: stay invested. Corrections of 20, 30, or 50% are part of the landscape. They occur every 5 to 7 years on average. This is the price to pay for returns that banking products cannot offer. This volatility is the filter that separates patient investors from those who sell at the worst moment.
Ready to take action?
Compare ETF strategies adapted to the Belgian context, or simulate your situation with our calculator.
Last updated: May 2026