📖 How spread, swap and commissions work in Forex
Every FX trade carries costs: some are charged at entry (the spread and sometimes a commission), others accrue while you hold the position (the swap). These costs quietly erode returns, especially in active strategies with frequent entries and exits.
This guide explains—in plain language—what the spread, swap, and broker commission are; when a swap can be positive or negative; how to compute the all‑in cost of a trade across Standard, STP, and ECN accounts; and practical ways to reduce these costs.
🧭 How to read quotes: base/quote currency, Bid/Ask, pip and lot
Before we break down costs, let’s define the core terms you’ll meet in any currency‑market trade.
Base and quote currency. In EUR/USD, the currency on the left (EUR) is the base; the one on the right (USD) is the quote. The price tells you how many units of the quote buy one unit of the base (e.g., 1.0950 USD per 1 EUR).
Bid and Ask. Bid is the price at which the market is willing to buy the base currency (you sell at Bid). Ask is the price at which the market is willing to sell the base currency (you buy at Ask). Ask is always above Bid.
Spread. The difference between Ask and Bid in pips. This is your “starting” cost: entering at Ask puts you immediately at a loss equal to the spread, because you could only close instantly at Bid.
Pip. The minimum price increment: for most pairs — 0.0001; for JPY pairs — 0.01. Some platforms show a “fifth digit” as a fractional pip (point), but core calculations use pips.
Lot and pip value. A standard lot equals 100,000 units of the base currency. For EUR/USD at 1 lot, 1 pip ≈ $10; at 0.1 lot — ≈ $1. You need this to convert spreads and swaps from pips into money.
💱 Spread: types, drivers, and calculation in money
Spread is the Ask–Bid difference. It’s embedded in the execution price at entry and shifts your breakeven away from the entry price.
Fixed vs. floating spread
- Fixed spread. Kept constant by the broker in normal markets. Pro — predictable costs; con — typically higher than an average floating spread during quiet hours.
- Floating spread. Moves with the market: tighter in calm periods, wider around news or low liquidity. It’s economical in “normal” time but less predictable.
What drives the spread
- Pair liquidity. “Majors” (EUR/USD, USD/JPY, etc.) trade more and have tighter spreads; crosses and exotics are wider.
- Sessions and overlaps. When European and U.S. sessions overlap, spreads are often at their narrowest; deep night is the opposite.
- Volatility and news. Before and right after macro releases, spreads widen and transactions temporarily “cost more.”
- Account type. On Standard, part of broker revenue is built into the spread; on STP/ECN, spreads are closer to interbank and often tighter.
Calculating spread in money
🔄 Swap: overnight rollover, “triple” Wednesday, and carry trade
Swap is the debit/credit for rolling a position overnight at a predefined settlement time. It reflects the interest‑rate differential between the pair’s currencies.
When the swap is positive or negative
- Negative swap. Holding the lower‑rate currency against a higher‑rate currency results in a rollover debit.
- Positive swap. Holding the higher‑yielding currency against a lower‑yielding one results in a credit. This underpins carry trade — seeking to earn the rate differential.
How to estimate the swap
💰 Broker commissions and account models (Standard, STP, ECN)
Commission is an explicit per‑lot fee charged on execution. On Standard it’s usually absent (the cost is “in the spread”); on STP/ECN it’s charged separately while spreads are noticeably tighter.
Standard (market maker/Dealing Desk)
An “all‑in‑spread” cost structure. Suits infrequent trades with small size and beginners who value simplicity.
- Pros: predictable, no explicit commission.
- Cons: wider spreads and a breakeven further from entry.
Bottom line: if you trade infrequently and small, simplicity often matters more than the absolute tightest spread.
STP (straight‑through to liquidity providers)
Market‑like spreads; the commission may be charged separately or “baked” into a small markup.
- Pros: closer to market pricing; pip savings for active trading.
- Cons: spread is more volatile; conditions depend on time of day and news.
Bottom line: a practical balance between simplicity and market‑level execution.
ECN (Electronic Communication Network)
Ultra‑tight spreads (down to 0.0) plus a transparent per‑lot commission. Preferred for active and algorithmic strategies.
- Pros: savings on every pip; often better execution.
- Cons: the commission is noticeable at very small sizes and with rare trades.
Bottom line: if you count every pip and place many trades, ECN usually wins on total cost.
📊 Summary table of costs: when and how they’re charged
The figures below are typical orders of magnitude for 1 lot in quiet hours. On a live account, use the instrument specification and your account type.
| 💱 Cost item | When it arises | How to calculate | Typical magnitude |
|---|---|---|---|
| Spread | At entry | Pips × $/pip × lots | ~0.4–1.5 pips (majors) → $4–$15 |
| Commission | Opening/closing | Per‑lot tariff (per side/round‑turn) | $5–$8 per lot (round‑turn) |
| Swap | Each rollover | Rate differential × notional ÷ (360/365) | Fractions to several $/day; Wednesday ×3 |
🔢 Calculation examples: scalping, swing, and carry‑trade
Numbers are hypothetical but realistic. Your actual economics depend on the pair, time of day, liquidity provider, and account settings.
Case 1. Intraday trade without rollover (1 lot)
- 💵 Entry: spread 0.6 pips ≈ $6 + commission $3 (per side) → $9.
- 🚪 Exit: commission $3 → another $3.
- 🔄 Swap: none (closed before rollover).
Case 2. Swing with a 2–3‑night hold
- 💵 Entry: ~$9.
- 🔄 Swap: −$1.5/day × 2–3 = −$3–$4.5 (if Wednesday is included — up to ~−$6.5–$7).
- 🚪 Exit: ~$3.
Case 3. Position idea with a positive swap (carry)
- 💵 Entry: ~$9.
- 🔄 Swap: daily +$1.2 → over 30 days ~+$36.
- 🚪 Exit: ~$3.
🛠️ How to reduce costs: a toolbox
You don’t need every tip — pick 2–3 that match your trading frequency and size.
Trade during narrow‑spread windows
These often coincide with session overlaps. Avoid thin‑liquidity hours and major releases when spreads widen and push breakeven further away.
Test execution on a demo/cent account
Check actual spreads and commissions with your broker during your hours. Compare Standard and ECN on identical scenarios.
Match position size to the fee plan
Per‑lot ECN commissions at very small sizes can eat the savings from tighter spreads. If you trade rarely and small, a no‑explicit‑commission account can be cheaper.
Plan rollovers
Close positions before rollover if the strategy doesn’t require holding. If rollover is inevitable, account for the Wednesday “triple” swap and your pair’s swap table.
Account for “off‑market” expenses
Account‑currency conversion, deposit/withdrawal fees, and inactivity charges are costs too. Keep a separate log of these expenses.
Bottom line: implementing just 2–3 well‑chosen techniques can materially cut costs. You don’t have to apply everything.
🧨 Typical beginner mistakes
❌ Comparing “raw” spreads
- Comparing ECN and Standard without factoring commissions is misleading. Always compute total trade cost.
❌ Trading in thin hours
- At night and on holidays, spreads widen and worsen expectancy for small profit targets.
❌ Ignoring Wednesday
- The triple swap can eat a large share of the profit of a long‑held position.
❌ Wrong account type
- For frequent trades, Standard is costly due to spread; for rare trades, ECN can be overkill due to commission.
📚 Glossary: key terms in two lines
- Forex (FX): a global over‑the‑counter currency market; trading runs 24/5 with no single central exchange.
- Base/quote: left/right currency in a pair; the price shows how much of the quote buys one unit of the base.
- Bid/Ask: market buy price / market sell price for the base currency; Ask is above Bid.
- Spread: Ask − Bid, measured in pips; your initial “cost of entry.”
- Pip: the minimum price increment; usually 0.0001, for JPY pairs — 0.01.
- Lot: a standard size of 100,000 units of the base currency; mini — 0.1; micro — 0.01.
- Pip value: the dollar value of 1 pip for your chosen size and pair.
- Volatility: the amplitude and speed of price change; raises risk and widens spreads around events.
- Rollover: moving open positions to the next day with a swap debit/credit.
- Swap: the debit/credit for rollover, driven by the interest‑rate differential between the pair’s currencies.
- Carry trade: a strategy aiming to earn a positive swap; price risk remains.
- Standard/STP/ECN: account models: “all‑in spread” / straight‑through / ECN; a balance between spread width and explicit commission.
- Round‑turn: the full “entry + exit” cycle, sometimes priced as a single commission amount.
- Liquidity provider: a bank or major participant that quotes two‑way prices and executes orders.
- Slippage: execution at a price different from the requested one; common in fast markets.
- Requote: a new‑price proposal if the old price is no longer available; more common with manual order handling.
📆 Monthly series: ECN vs. Standard by the numbers
Compare simplified monthly scenarios to see the effect of scale.
Day trader: 100 trades at 1 lot
- 💵 ECN: spread ~0.5 pips → ~$5 × 100 = ~$500; commission ~$6/lot × 100 = ~$600. Total ≈ $1,100.
- 📦 Standard: spread ~1.5 pips → ~$15 × 100 = ~$1,500; no commission. Total ≈ $1,500.
Swing trader: 12 trades, 2‑night hold
- 💵 ECN: entry/exit ≈ $12 × 12 = $144; swap ~−$2 × 2 × 12 = −$48. Total ≈ $192.
- 📦 Standard: entry/exit ≈ $15 × 12 = $180; same swap. Total ≈ $228.
❓ Questions & Answers (FAQ)
Can I avoid paying swaps altogether?
Fixed or floating spread — which is better for a beginner?
Is a no‑commission account always cheaper?
Will there be a swap if I close the trade the same day?
Why is Wednesday’s swap triple?
Can you “earn on the swap”?
✅ Conclusion
Forex trading costs are not just the spread — they also include per‑lot commissions and recurring swaps. Together they form the real price of a trade and change a strategy’s expectancy. Knowing how and when each component is charged lets you control breakeven and protect your results.
Practical plan: trade during narrow‑spread hours, choose the account type to match your frequency and size, calculate the full entry/exit cost in advance, plan rollovers with Wednesday in mind, and keep a log of “off‑market” fees. These steps deliver measurable benefits in the first month.