Ask what a trade "costs" and most people quote the spread. That's one line item out of five, and for anyone holding longer than a few hours it usually isn't the biggest one. Here's how to build the full number for a trade you actually plan to place, using our cost calculator or the arithmetic below.
The five line items, in the order they hit
- Spread — paid the instant you open the position, built into the price itself. This is the only cost most comparison tables show.
- Commission — a fixed per-lot charge, if your account type carries one, added on top of a tighter spread rather than replacing it.
- Swap / overnight financing — charged once per calendar night you hold the position past the broker's cut-off, and tripled on one night a week to cover the weekend. See what holding a trade overnight costs for the mechanics.
- Currency conversion — applies only if the instrument's currency differs from your account currency; easy to miss because it never appears as a separate line on your statement.
- Non-trading fees — inactivity charges, withdrawal fees or account fees that have nothing to do with this specific trade but still come out of the same balance. See inactivity fees explained.
A trade closed within the same day only ever touches items 1 and 2. Everything past an overnight hold has to account for item 3 as well, and it compounds every extra night you stay in.
A worked example
Illustrative numbers — plug your own broker's published figures into the cost calculator for a real answer. Say you open a 1-lot EUR/USD position (100,000 units) on a raw-spread account:
- Spread: 0.1 pips ≈ $1 round turn (in and out).
- Commission: $6 per round lot, round turn.
- Swap: −0.6 pips per night held long ≈ $6/night.
- Held 9 nights, including one Wednesday triple-charge night, so that's 11 chargeable nights ≈ $66.
- No conversion fee — account and instrument currency match.
Total: $1 + $6 + $66 = $73 to hold and close this one trade — and $66 of it, over 90%, is swap that a spread comparison would never have shown you. Shorten the hold to a single day and the same trade costs $7. The holding period, not the broker's advertised spread, decided which number was true.
Why the "cheapest broker" answer changes with your own numbers
Run the same worked example for a scalper doing ten round trips a day and swap barely registers — spread and commission dominate, so a broker with a slightly wider spread but zero commission could easily lose that comparison. Run it for a swing trader holding for three weeks and commission becomes the rounding error while swap and any conversion fee dominate. There is no single "cheapest broker" answer independent of how you trade — see raw-spread vs standard accounts for how the account type itself shifts which line item matters most.
Building your own number
- Pull your broker's published spread, commission and swap rate for the instrument you actually trade — not a "from" headline figure.
- Multiply spread and commission by your typical trade size and frequency for a month.
- Multiply the swap rate by your average holding period in nights, remembering the weekly triple-charge night.
- Add any non-trading fees that apply to your account regardless of trading — inactivity or withdrawal charges.
- Compare the total, not any single line item, across brokers on our fees comparison.
That total is the number worth comparing broker to broker. The headline spread on its own tells you almost nothing about what a real position costs to hold.
Figures used here are illustrative; published rates change and vary by account type and instrument. Verify current pricing with your broker before you trade. Educational content, not financial advice.