Commission vs Spread: Which Trading Cost Is Better?

Spread Cost: How It Works

Spread is the difference between the bid price (what you can sell at) and the ask price (what you can buy at). If EUR/USD shows 1.0850 bid / 1.0851 ask, the spread is 1 pip. You effectively pay 1 pip the moment you enter a trade — if you closed immediately, you would lose 1 pip.

On a standard lot (100,000 units), 1 pip on EUR/USD is $10. So the round-turn cost of that trade is $10 in spread. Spreads vary: majors 0.1–2 pips, minors 1–3 pips, exotics 5–15 pips, stocks depend on liquidity. "Commission-free" brokers add 0.5–1.5 pips to interbank spreads as their markup — this is where they make money.

Commission Cost: How It Works

Commission is a flat fee charged per standard lot (or per $100k notional) regardless of spread. On ECN accounts, commission is typically $3.5 per lot per side, or $7 round-turn. The spread itself is tight (often 0.0–0.3 pips on majors) because the broker is not marking it up.

On a $100k EUR/USD trade with 0.1 pip spread + $7 commission: total cost is $1 (spread) + $7 (commission) = $8 round-turn. Compare to MM broker: 1.5 pip spread = $15 round-turn, no commission. ECN saves $7 per standard lot in this case. Commission models scale linearly with lots, so at 10 lots/day = $70/day in commissions, but savings on spread (vs MM) = $140/day.

The Crossover Point

At what volume does commission become cheaper than spread? Formula: if commission per round-turn = C and spread difference = S (in $ per lot), commission is cheaper once C < S. For EUR/USD: ECN $8 vs MM $15 → ECN cheaper from trade 1. For less liquid pairs: MM spread might be 2 pips ($20), ECN spread 0.5 pip + $7 commission = $12 — still cheaper.

Commission only loses to spread on very thin instruments where ECN spreads balloon during volatile hours. For mainstream pairs, ECN is almost always cheaper for any active trader. Calculate your specific pairs' all-in cost per broker using 1-month data — do not trust marketing claims.

"No Commission" Marketing Traps

"Zero commission" is a popular tagline at MM brokers, eToro, Robinhood, and even some forex platforms. Mathematically it is usually misleading — the cost is baked into wider spreads. A "commission-free" stock CFD platform charging 0.15% spread on Apple is identical to a commissioned platform with 0.05% spread + 0.10% commission.

The psychological trick works: clients remember "I didn't pay commission" and forget the 3x wider spread they paid on every trade. Regulators (MiFID II, SEC) now require "total cost of ownership" disclosures, but most clients skip these. Always compare all-in cost per round-turn on your actual trades — that single number reveals the truth.

Which Structure Fits Your Strategy

Scalpers (sub-5-pip targets, 10+ trades/day) should use ECN with commission — every 0.5-pip spread saving compounds massively. A scalper doing 20 lots/day saves $70–140/day on ECN vs MM, which is $18k–36k/year.

Swing traders (50+ pip targets, 1–3 trades/week) are roughly indifferent — the spread vs commission difference is small relative to targets. Use whichever broker has better platform, regulation, or other features.

News traders and high-slippage pairs (exotic crosses) benefit from ECN due to tighter spreads during liquid hours, but commission-spread on thin hours can be wider. Run 30 days of logs on each broker before making a final decision.