To buy a share or an ETF you need a broker: the company that takes your order to the stock exchange and holds what you buy. Choosing one is simpler than it looks if you know what to check. Our view, for anyone who does not want to read further: Trading 212 to start with, and Interactive Brokers once your savings grow. Below we explain why, and which alternatives we compare them with.
No broker pays us to appear in this article.
What to check in a broker
Safety. What you buy does not belong to the broker, it belongs to you. It works like a theatre cloakroom: if the theatre goes bust, your coat is still yours and they have to give it back. By law, the broker holds your shares separately from its own, usually through a custodian, the institution where they are deposited. And if something really goes wrong and securities are missing, each country has an investor compensation scheme. In Germany and Ireland, where the two brokers we recommend are based, it covers 90% of what is missing, up to 20,000 euros per person. That scheme protects you from the broker failing, not from your shares falling in price.
Fees. Three matter: what it charges on each purchase or sale, what it charges to convert euros into dollars when you buy something priced in dollars, and whether it charges anything for holding your shares.
Tax. In many countries a local broker reports to the tax office for you and withholds tax. A foreign one generally does not: you declare it yourself. In Spain, for example, if what you hold abroad goes over 50,000 euros you must also file form 720, which is only informative. It is no reason to rule out a foreign broker, but worth knowing beforehand.
Trading 212: the one we use and recommend to start with
Carlos Darder, founder of Catallaxis Capital, invests with Trading 212. For clients in the European Union it is run by Trading 212 EU GmbH, a German company supervised by the German financial regulator, BaFin. The securities are held by Interactive Brokers and Bank of New York Mellon, depending on the market, and the German compensation scheme covers 90% up to 20,000 euros per person if Trading 212 could not return them.
Its advantage is cost: 0 euros to buy or sell shares and ETFs, no custody fee, and 0.15% when you convert currencies. You can buy fractions of a share from 1 euro, so with 50 euros a month you can own part of a company whose share costs 400. And the app is the simplest we know: someone who has never invested can get the hang of it in an afternoon.
Its limits: it has no index funds, only ETFs, and as a foreign broker for most Europeans you declare the gains yourself.
Interactive Brokers: once your savings grow
Interactive Brokers is one of the largest brokers in the world. It is listed on the Nasdaq, and on 30 June 2026 it had 5.19 million client accounts and total equity of 22.3 billion dollars. Clients in the European Union are served by Interactive Brokers Ireland, supervised by the Central Bank of Ireland and a member of the Irish compensation scheme, which covers 90% up to 20,000 euros.
Why move to it when you have more money. The compensation scheme of Trading 212 or Interactive Brokers covers at most 20,000 euros. With 5,000 euros invested that cover is plenty; with 200,000, it stops counting and what matters is how solid the broker is. On that, Interactive Brokers is hard to beat. It also gives access to many more stock exchanges. In return it charges something on each trade, around 0.05% on European exchanges, with a minimum of between 1.25 and 3 euros depending on the price plan, and its platform is built for experienced investors: at first it is overwhelming.
If you live in the United States
Everything above is written for European investors. For Americans, the equivalent of Trading 212 is Robinhood: a simple app and, as its own annual report states, the first US broker to offer commission-free stock trading with no account minimum. Accounts are held by Robinhood Financial, a registered broker-dealer and member of SIPC, the US scheme that covers up to 500,000 dollars per customer, including 250,000 in cash, if the broker fails. Like the European schemes, it does not cover falls in market value.
It is worth knowing how it makes money without charging commission: a large part comes from payment for order flow, selling its customers’ orders to market makers. It is legal in the United States, but it means you pay through the price at which your order is executed rather than through a visible fee. For Americans, Interactive Brokers is also the step up once savings grow.
Robinhood also operates in Europe, but there it sells stock tokens: a product that follows the price of a share, not the share itself. For a European we prefer a broker that buys you the real share.
The alternatives
The fees below are those of each broker’s Spanish price list; in other countries they may differ.
| Broker | Who it is | What it charges | What it is good for |
|---|---|---|---|
| DEGIRO | flatexDEGIRO Bank SE, a German bank | Spanish or US shares, €1 + €1 per trade. ETFs in its core selection, €1; other ETFs, €2 + €1 | One of the most widely used in Europe, with many markets |
| Trade Republic | Trade Republic Bank GmbH, a German bank | €1 per trade. Regular savings plans, free | Automatic monthly contributions |
| MyInvestor | A Spanish institution supervised by the Bank of Spain and the CNMV | ETFs, 0.12% (min. €1, max. €25). Shares, 0.12% (min. €3, max. €25). Currency conversion, 0.30% | For Spanish residents: switchable index funds, and it reports to the tax office for you |
| XTB | XTB SA, a Polish company | €0 on shares and ETFs up to €100,000 a month; above that, 0.2% (min. €10). Currency conversion, 0.5% | Zero cost, like Trading 212 |
If you live in Spain and prefer index funds, MyInvestor is the option on this list built for them, because of the tax advantage of switching that we explain in Index fund or ETF: what is the difference. DEGIRO and Trade Republic charge per trade what Trading 212 does not, and with small contributions a fixed euro weighs: on a 50 euro purchase it is 2%. XTB costs the same as Trading 212 up to 100,000 euros a month, but charges 0.5% to convert currencies, against 0.15%.
What we stay away from
Many brokers, including some on this list, also sell CFDs: contracts that do not give you the share, but a bet on its price, almost always with leverage. XTB warns on its own website that 77% of retail investor accounts lose money with CFDs. That is not investing. If you open an account, make it the investment account, not the CFD one, and be wary of any broker that pushes you to trade with leverage.
In short
To start with little: a broker with no trading fees, simple, and with custody at solid institutions. That is why we use and recommend Trading 212. For index funds in Spain: a Spanish broker with fund switches. Once your savings grow: how solid the broker is matters more than saving a euro per trade, and there Interactive Brokers is our choice.
How to open the account, what to buy and how to leave your monthly plan running is what we do in the first session. If you are starting from scratch, the earlier steps are in Start investing from scratch.
Educational content and Catallaxis Capital’s opinion based on our experience. Not personalised financial advice. Fees and terms are those published by each broker on 27 October 2026 and may change: check them on their website before opening an account.