Take a German investor building a long-term portfolio in US ETFs. She opens an account with a USD-only broker, spends weeks comparing commissions, picks the zero-commission option, and feels good about the decision. What she doesn’t notice: every time she wires euros into her account, her broker converts at a rate 1.5% below the interbank mid-market. Four deposits a year. €5,000 each. That’s €300 disappearing quietly every year - not as a fee, not as a line item, just as a slightly worse exchange rate. Over ten years, with compounding, that’s closer to €4,000 gone.
The broker she almost chose instead charged $0.03 per $100 converted. The same four deposits would have cost her about $12 per year total.
That gap - between a lazy FX setup and a deliberate one - is what this guide is about. Not which broker has the prettiest app. Which one handles your money across currencies without bleeding you at the exchange rate.
The numbers above aren’t hypothetical. On a $100,000 portfolio with four deposits a year, a 1.5% FX markup costs roughly $6,000 over ten years. The best brokers charge 0.03 basis points - the same deposits cost about $120. The difference is $5,880, and most reviews don’t mention it at all.
Here are the accounts that get this right.
Why FX Costs Matter More Than Commissions
When you’re an international investor, every trade that crosses a currency border involves a conversion. You fund your account in euros or shekels or Singapore dollars. You buy US-listed ETFs denominated in USD. You eventually withdraw back to your home currency. Each of those steps can cost you - and the markup isn’t always labeled as a fee.
Most brokers embed the FX cost in the exchange rate itself. They convert at a rate that’s 0.5% to 2% worse than the interbank mid-market rate, pocket the difference, and show you a $0 commission. The trade looks free. It wasn’t.
The brokers in this guide are the ones that actually show you what FX costs, charge it transparently, and charge it cheaply.
The Top Options
1. Interactive Brokers - The Best Overall
IBKR is the default answer for most serious international investors, and the FX workflow is the main reason why.
Currency conversion at IBKR costs 0.03 basis points (0.0003%) with a minimum commission of $2. The numbers are worth making concrete: an Israeli investor converting ₪20,000 (roughly $5,500) to USD pays $2 at IBKR. The same conversion at a typical Israeli bank with a 1.2% spread costs around $66. Do that eight times a year and IBKR saves you over $500 annually on funding costs alone - before a single trade.
The account supports funding in 29 currencies. You can hold balances in multiple currencies simultaneously without forced conversion - euros and USD and GBP can coexist in the same account, each earning their respective interest rates, and you convert only when you choose to. That “convert on purpose” approach is one of IBKR’s most underrated features. If your trading currency and funding currency match, you skip the conversion entirely.
IBKR also integrates directly with Wise. Clients can fund their IBKR account using Wise Balance at the true mid-market rate, with a fixed transfer fee of around $0.39. That combination - Wise for the currency move, IBKR for the investment - is close to the theoretical minimum for FX drag on a cross-currency investing workflow.
Beyond the FX side: 150+ global markets across 33 countries, margin rates around 5-6% for most balances, competitive cash yields (up to 3.14% on USD balances above $100k as of May 2026), and SIPC protection plus supplemental Lloyd’s of London coverage. The platform is genuinely complex - Trader Workstation is not something you open for the first time and immediately understand - but the GlobalTrader mobile app offers a more accessible entry point.
FX cost: 0.03 basis points + $2 minimum Supported funding currencies: 29 Best for: Serious long-term investors, anyone making regular cross-currency deposits, multi-market portfolios
2. Saxo Bank - The Premium Multi-Asset Option
Saxo is a Danish investment bank with a different positioning than IBKR - closer to a private bank experience, with 70,000+ instruments across every major asset class and a platform quality that consistently wins industry awards. For multi-currency specifically, it supports account funding in 21 currencies and allows sub-currency accounts to manage FX exposure separately within a single account structure.
The FX story at Saxo is more complicated than at IBKR, and it depends heavily on which account tier you’re on.
Classic accounts (no minimum deposit in most countries) convert currencies at mid-FX ±0.25%. That’s reasonable but not competitive with IBKR. Classic accounts also carry a 0.15% annual custody fee on stock, ETF, and bond holdings - a cost that rarely gets highlighted in reviews but matters significantly for buy-and-hold investors. A $100,000 stock portfolio pays $150/year in custody fees before any trading commissions. Over ten years, that’s $1,500 in a cost that IBKR doesn’t charge at all.
Platinum accounts (€200,000 minimum) get better rates. VIP accounts (€1,000,000 minimum) get the tightest FX spreads - 0.25% - and waived or reduced custody fees. At the VIP tier, Saxo genuinely competes. Below that, the cost structure favors active traders who generate enough commission to offset the custody drag.
Where Saxo wins clearly: 190 currency pairs, platform depth and usability (SaxoTraderGO and SaxoInvestor are genuinely excellent), and the feel of a properly regulated bank. It’s regulated in 15 countries, holds a full banking license in Denmark, and client funds are segregated. For investors who value platform quality and want a near-private-bank experience, Saxo justifies its cost premium.
FX cost: ±0.25% (Classic), tighter at higher tiers Supported funding currencies: 21 Best for: Active traders and high-net-worth investors who value platform depth; less ideal for passive buy-and-hold at Classic tier
3. The IBKR + Wise Combination
Strictly speaking, Wise isn’t an investment account. You can’t buy stocks or ETFs through it. But for international investors using IBKR, the Wise integration changes the economics of cross-currency funding enough that it deserves its own section.
The setup: you hold your home currency in Wise (which supports 40+ currencies), convert at Wise’s mid-market rate with a transparent small percentage fee, and transfer to IBKR with a fixed fee of around $0.39. Funds arrive in IBKR in the converted currency and are available for trading immediately once posted.
The practical effect is that you bypass your local bank’s FX markup entirely. For investors in countries where local bank wire fees and FX spreads are high - which covers most of the world - this combination can save hundreds of dollars per year on funding costs alone.
Wise itself is regulated by the FCA in the UK and multiple other jurisdictions, holds client funds in segregated accounts, and has processed over $100 billion in transfers. It’s a legitimate, well-regulated piece of infrastructure, not a workaround.
FX cost at funding stage: Wise’s transparent percentage fee (varies by currency pair, typically 0.4-1.0%) + $0.39 transfer to IBKR Best for: Investors in countries with expensive local bank FX or wire fees
4. HSBC Expat - The Banking Solution
HSBC Expat is in a different category than the brokers above - it’s a full-service offshore bank based in Jersey, not a discount brokerage. But for certain investors, particularly those with significant assets and complex cross-border financial lives, it solves problems the pure brokers don’t.
The multi-currency capability is genuine: you can hold balances across multiple currencies in one place, access international mortgages, make free transfers between Citibank accounts worldwide via HSBC’s global network, and manage currency positions alongside actual banking services. The investment range includes global equities, ETFs, bonds, and funds.
The significant catch is the entry point. Fee-free access requires a CitiGold account with a minimum combined balance of $200,000. Below that, monthly fees and reduced international perks change the value calculation considerably. HSBC has also been reducing its physical branch presence in a number of countries, which limits its accessibility in some markets.
For a high-net-worth investor who needs banking, investing, and multi-currency management in one place and can meet the balance threshold, HSBC Expat is a serious option. For everyone else, the balance requirement and banking overhead make it the wrong tool.
FX cost: HSBC’s proprietary exchange rate, below interbank mid-market Best for: HNW investors with $200k+ who need full banking services alongside investment accounts
Comparison Table
| IBKR | Saxo (Classic) | Saxo (VIP) | HSBC Expat | |
|---|---|---|---|---|
| FX Conversion Cost | 0.03 bps + $2 min | ±0.25% | ±0.25% (tighter) | Proprietary rate |
| Supported Currencies | 29 | 21 | 21 | Multiple |
| Custody Fee | None | 0.15% p.a. | Reduced/waived | N/A |
| Minimum Deposit | $0 | $0 (most countries) | €200,000 | ~$200,000 |
| Market Access | 150+ markets | 70,000+ instruments | 70,000+ instruments | Global |
| Wise Integration | Yes (native) | No | No | No |
| Cash Yield | Up to 3.14% (USD, $100k+) | None (Classic/Platinum) | Yes (VIP only) | Yes |
| Platform Complexity | High | Moderate-High | Moderate-High | Moderate |
| Regulation | SEC, FINRA | 15 countries, Danish FSA | Same | FCA, Jersey FSA |
How to Choose
The right account depends on what you’re actually doing with your money.
If you’re building a long-term, diversified international portfolio and making regular deposits from a non-USD account, IBKR is almost certainly the right answer. The FX cost advantage compounds over time, the market access is unmatched, and the Wise integration makes funding close to frictionless. The platform takes time to learn, but you don’t need to use all of it - most long-term investors use a fraction of IBKR’s features and still benefit from the fee structure.
If you’re an active trader who values platform experience and is willing to pay for it - or if you’re operating at the Platinum/VIP tier where Saxo’s costs become more competitive - Saxo makes sense. The instruments available, the platform quality, and the bank-level security are genuine advantages. Just model out the custody fee cost over your expected holding period before committing.
If your main problem is expensive local bank FX rather than broker choice, set up the Wise + IBKR combination before worrying about anything else. It’s the single highest-ROI change most international investors can make to their setup.
If you have $200k+ and want genuine offshore banking alongside investments, HSBC Expat deserves a serious look. The balance threshold is high but the product breadth is real.
What to Do Today
If you’ve read this far, you probably recognize your own setup somewhere above. Here’s how to act on it.
Step 1: Open an IBKR account. It’s free, there’s no minimum deposit, and the application takes 20-30 minutes. Even if you don’t move your entire portfolio immediately, having the account open means you can start using it for new deposits.
Step 2: Link Wise to your IBKR account. Create a Wise account if you don’t have one, verify it, and connect it to IBKR using the “Pay with Wise” integration in the IBKR Client Portal. Your next deposit will cost a fraction of what your bank charges.
Step 3: Do the math on your current setup. Find your last three or four broker deposits. Calculate what percentage you lost to FX conversion. If it’s above 0.5%, you now know exactly how much you’re saving by switching.
The first transfer tends to be the moment it clicks. Seeing $2.00 on the IBKR conversion confirmation, versus whatever your bank was charging, makes the case more clearly than any guide can.
This article is for informational purposes only and does not constitute financial or investment advice. Fee data is sourced from official broker pricing pages and verified third-party reviews. Exchange rates, account minimums, and features are subject to change - verify current terms directly with each provider before opening an account.
