Eligibility and ETF access first, then FX workflow. If you can’t reliably open or keep the account, or can’t buy the ETFs you’re allowed to buy (UCITS vs US-domiciled), no broker ranking matters. Fix those two constraints first, then optimise cost.

Because long-term investors fund accounts repeatedly. If each monthly contribution triggers a EUR to USD conversion at a 0.5–1% spread, that leakage compounds every month for years and routinely exceeds what you’d ever pay in visible commissions.

The fix: a multi-currency account (IBKR) where you convert once at near-institutional rates, then hold and buy from that balance without triggering further conversions.

No. UCITS ETFs track the same underlying indexes as their US equivalents. The exposure is identical; only the wrapper differs. Your focus shifts to: which UCITS listings your broker offers, their spread quality, and the FX workflow.

Non-US investors holding US-domiciled ETFs (such as VTI, SPY, or QQQ) hold assets classified as US-situs property. Non-US individuals face a much lower estate tax exemption threshold than US citizens — assets above that threshold can be subject to US estate tax at rates up to 40% on death, regardless of where the investor lives.

UCITS ETFs domiciled in Ireland or Luxembourg are generally not US-situs assets and are not subject to this tax. For non-US investors with meaningful portfolios who can access US ETFs, this distinction matters when choosing which ETF wrapper to hold. Verify your specific situation with a cross-border tax professional.

It’s the strongest default for most non-US investors because it addresses the two biggest pain points: eligibility breadth and FX workflow. But it’s not universally correct. If a simpler local broker covers your eligibility, has acceptable costs, and you’ll actually use it consistently, that can be the better behavioral choice.

Neither in isolation. For long-term ETF investing, choose the broker with the best combination of eligibility, FX workflow, safety, and tax reporting. A small cost saving is meaningless if the broker creates friction, forces bad currency conversions every month, or leaves you with a tax-reporting headache every year. Safety and cost are both factors — neither dominates blindly.

Sometimes. Local brokers may provide country-specific tax reports or handle certain obligations automatically — for example, Italian brokers operating under regime amministrato handle Italian capital gains tax on behalf of the client, removing significant admin. IBKR provides detailed raw statements but rarely offers country-tailored outputs. For large portfolios, the lower FX and custody costs at IBKR usually outweigh the reporting inconvenience. For smaller portfolios where admin time is the binding constraint, a local broker can be rational.

Invest monthly (income is monthly). For FX: if your broker’s spread is wide, batch the conversion into a larger, less frequent transaction rather than converting a small amount on each trade. On IBKR, you can deposit monthly in EUR and convert quarterly — just avoid sitting in uninvested cash for long periods.

Not always, but they matter most for small monthly contributions. If your monthly amount is below the price of a single ETF unit, fractional investing keeps cash fully deployed rather than sitting idle. For contributions above the cost of a full unit, this constraint becomes much less relevant. Brokers offering fractional ETF investing include Trading 212, IBKR, and Lightyear.

Optimising for the wrong variable — usually a small advertised commission difference — while ignoring FX spreads, eligibility constraints, and how the platform affects their own trading behaviour. The largest long-run edge is consistency with low friction, not chasing the cheapest headline rate.