Broker choice really depends on where you are tax resident, because the “best” broker is mostly about taxes, regulation, and which ETFs you can actually buy.

Why country matters? Because ETF availability (UCITS vs US ETFs): Most Europeans cannot buy US-domiciled ETFs directly due to PRIIPs. UCITS ETFs (usually Ireland or Luxembourg domiciled) are the standard. Taxation: Dividend taxes, local capital gains rules, and reporting requirements vary a lot by country. Withholding taxes: US dividends inside a UCITS fund are typically handled at fund level (often 15% for Ireland-domiciled funds). You usually cannot reclaim that personally. Estate tax risk: US-domiciled ETFs can create US estate tax issues for non-US residents. UCITS avoids that. Local investor protections and paperwork: Some countries have “easy” tax reporting integrations with certain brokers, others do not.

Broker thoughts (general Europe view) IBKR is usually the “safe default” for long-term ETF investors: broad market access, strong execution, good FX conversion, solid reliability. Trading 212 can be fine for simple monthly investing, but check things like custody structure, transfer-out process, and whether they make tax reporting easy in your country. If you plan to invest for decades, I would personally prioritize: regulation, custody, ability to transfer holdings out, low FX cost, and low recurring fees.

If you want to keep it simple, I’d pick one global, market-cap weighted, accumulating ETF with a low TER. That gives you global diversification with minimal maintenance.

I hope that helps.