The biggest investing mistake is waiting until you "have enough" to start. Thanks to compound interest, starting with €50 per month at 25 beats starting with €500 per month at 40.
The compound interest reality
Compound interest means you earn returns on your returns. €1,000 invested at 7% annual return becomes €1,070 after year one, then €1,145 after year two — and the growth accelerates over time. Over 30 years, that €1,000 becomes approximately €7,600. The same amount invested for 20 years is only €3,870. Time in the market is everything.
What to actually invest in
For most beginners, low-cost index funds are the best starting point. An index fund simply tracks a market index (like the S&P 500 or a global fund) and automatically diversifies your money across hundreds or thousands of companies. You are not trying to pick winners — you are buying the whole market.
The key advantage: index funds have very low fees (0.05-0.20% annually vs 1-2% for actively managed funds). Over 30 years, that difference in fees can be worth tens of thousands of euros.
Where to invest
Platforms like Degiro, Trade Republic or eToro allow you to start investing with small amounts. In Spain, a pension plan (plan de pensiones) offers tax advantages. In many countries, ISAs or equivalent tax-efficient wrappers are worth using first.
The rules that matter most
Never invest money you might need in the next 3-5 years. Diversify across asset classes and geographies. Keep costs low. Stay invested during market downturns — time in the market beats timing the market. And above all: start.
