Broker Total Cost Calculator
“Commission-free” is rarely free. This calculator estimates your real all-in broker cost — commissions, FX conversion, bid-ask spreads, and custody fees — based on how you actually invest.
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What this calculator covers
- Trading commissions (with minimums)
- FX conversion — markup and fixed fee
- Bid/ask spread drag on each buy
- Platform and custody fees over time
- Annual drag in basis points for comparison
- ETF-level costs (TER, tracking difference)
- Dividend withholding tax layers
- Cash drag on uninvested balances
- Rebates, cashback, or tiered pricing
- Execution quality beyond spread assumptions
How to use this calculator
Three inputs drive most of your result: contribution size, FX frequency, and spread assumption. Get those right first.
Enter your real contribution amount and frequency. This determines how many times you pay each repeatable fee over the horizon.
Fill in commissions, FX markup, and custody fees from your broker’s fee schedule. Use 0 for anything that doesn’t apply.
The results panel ranks each cost component. Fix the largest one first — it’s usually FX or spreads, rarely the headline commission rate.
Estimate your all-in broker cost
Used only to estimate average balance for the bps number. Vary fee inputs to compare brokers, not this field.
Modelled as half-spread on each buy. 0.10% = typical liquid UCITS ETF (IWDA, CSPX).
Batching reduces fixed fees but creates cash drag between conversions.
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How to act on the result
Batch conversions quarterly instead of monthly, or switch to a broker with institutional FX rates. Interactive Brokers charges roughly 0.002% at scale — most neobrokers charge 10–100× that. Even batching alone can cut FX drag by 50–75%.
Use limit orders on the way in. Avoid trading in the first and last 15 minutes of the session. Prefer high-AUM ETFs — IWDA and CSPX regularly trade at under 0.03% during normal hours. Thin ETFs in the same index can trade 5–10× wider.
Consolidate buys: fewer, larger contributions save money when a minimum commission applies. Or use a commission-free broker (Trading 212, Trade Republic) for small recurring contributions and move to IBKR as the portfolio scales.
Percentage custody grows as your portfolio grows — it’s the cost that matters most at scale. Moving to a flat-fee or custody-free broker (IBKR, DEGIRO) above a certain portfolio size typically saves a meaningful amount per year. Calculate the crossover point.
Want the full cost model in a spreadsheet?
The EU Investor Cost Toolkit goes further: broker comparison across three scenarios, UCITS vs US ETF drag with withholding tax layers, 30-year projection with charts, and a full cost dashboard — all in one .xlsx file with 11 tabs and no macros.
30-day money-back guarantee. Educational content only — not personalized investment or tax advice.
Go deeper
Frequently asked questions
What counts as “total cost” for a broker?
For long-term investors it’s usually the repeatable leaks: FX conversion, spreads, platform/custody fees, and trade minimums. This calculator estimates those using your actual cadence. ETF-level costs (TER, tracking difference) and dividend withholding tax are fund-level costs that layer on top — they’re not included here.
Why does FX conversion come out so high?
Because you pay it on every contribution. A 0.20% markup is roughly €1 per €500 — small in isolation. But paid monthly for 10 years that’s €120+ before compounding effects. The fix is batching conversions quarterly or using a broker with institutional FX rates. Interactive Brokers charges roughly 0.002% at scale; most neobrokers are 0.15–0.50%.
Is spread cost real if I plan to hold forever?
Yes. You pay it on the way in — you buy at the ask, which sits above mid-price. Even if you never sell, each contribution buys slightly fewer units than at mid. Over hundreds of contributions this adds up to a real shortfall in units accumulated.
What does “annual drag in basis points” mean?
It converts your total lifetime fees into an approximate annualised drag using the estimated average balance. One basis point equals 0.01%. It’s designed as a comparison number: run the same inputs for two different brokers and compare the bps figure. It’s not a return forecast.
What should I optimise first?
The largest repeatable leak in your breakdown. Usually that’s FX frequency or spread assumptions. Commissions are rarely the main issue on contributions above €200–300. Fixed platform fees hurt small accounts most; percentage custody fees hurt large accounts over long horizons. Fix the line at the top of the breakdown chart.
Why isn’t ETF TER included?
TER is a fund-level cost, not a broker-level cost. This calculator focuses on broker execution costs so you can compare brokers and workflows independently. For a complete cost picture — including TER, tracking difference, and withholding tax layers — use the EU Investor Cost Toolkit, which models all layers together in one spreadsheet.
QuantRoutine provides educational content only. Nothing on this page is an offer, solicitation, or recommendation to buy or sell any security or to open an account with any specific broker. Calculator outputs are estimates based on your inputs and simplified modelling assumptions — real costs depend on execution quality, exact fee schedules, rebates, and account type. Spread assumptions in particular can vary significantly from actual execution. Always review each broker’s current terms and fee schedule before making decisions. You are responsible for your own financial decisions and for confirming the tax and legal rules that apply in your country.