Spread, slippage, liquidity

Every trade has a cost before it has a result. Spreads, commissions, and slippage are small on any single trade, but they are paid on every trade — and over hundreds of trades they decide whether a marginal strategy is profitable or not. Professionals obsess over execution costs. This lesson shows you how to measure them in real money, and how to keep them low.

What you'll learn

• What a pip is, and how to calculate pip value for a position
• How to convert the spread into a real cost in dollars
• The full cost of a trade: spread, commission, and swap
• What slippage is, what causes it, and which orders are exposed to it
• How liquidity ties all of this together

1. Pips and pip value

A pip is the standard unit for measuring price moves in forex.

• For most currency pairs, 1 pip = 0.0001 (the fourth decimal place). EUR/USD moving from 1.0850 to 1.0851 is 1 pip.
• For pairs quoted in Japanese yen, 1 pip = 0.01 (the second decimal place). USD/JPY moving from 150.20 to 150.21 is 1 pip.
• Many brokers quote an extra decimal — a pipette (a tenth of a pip). EUR/USD at 1.08503 is 1.0850 plus 3 pipettes.

Pip value tells you how much money 1 pip is worth for your position size. For pairs where USD is the second currency (EUR/USD, GBP/USD, AUD/USD):

For other pairs the pip value changes with the exchange rate — most platforms and position-size calculators show it for you.

2. The spread in real money

You buy at the ask and sell at the bid, so every round-trip trade pays the spread once.

Spread cost = spread (in pips) × pip value × lots

Worked example

(Illustrative.) EUR/USD spread is 1.2 pips. You trade 2 standard lots.

• Spread cost = 1.2 × $10 × 2 = $24

Your trade starts $24 down. It must move 1.2 pips in your favour just to break even.

Fixed vs variable spreads

• Variable spreads move with market conditions — tight during active sessions, wide during quiet hours and news.
• Fixed spreads stay the same in normal conditions, but are usually wider on average and may still change in extreme conditions.

3. The full cost of a trade

The spread is only one part of the bill.

Worked example: comparing two accounts

(Illustrative figures — compare your own broker's numbers.) You trade 1 standard lot of EUR/USD.

For someone trading 20 lots a month, that difference is $60 a month — $720 a year — without changing a single trading decision.

4. Slippage

Slippage is the difference between the price you expected and the price you actually got.

• Negative slippage: you get a worse price.
• Positive slippage: you get a better price — it happens too, and fair brokers pass it on.

What causes it

• Fast markets — price moves between the moment you click and the moment the order reaches the market.
• Thin liquidity — not enough size at the best price, so your order walks the book (see Buyers, sellers, order books, price discovery).
• Gaps — price jumps from one level to another with no trading in between (weekend opens, major news).

Which orders are exposed?

Worked example

(Illustrative.) You're long 1 lot of EUR/USD with a stop at 1.0830. A major US data release sends price sharply lower. Your stop triggers, but the next available bid is 1.0822.

• Slippage: 1.0830 − 1.0822 = 8 pips
• Extra loss: 8 × $10 = $80 beyond what you planned

If your planned risk was $200, the actual loss is $280 — 40% more than intended.

5. Liquidity: the thread connecting it all

Liquidity is how easily size can be traded without moving the price. High liquidity means:

• Tighter spreads — market makers compete to quote
• Less slippage — more size waiting at each price
• Cleaner fills on stop orders

Liquidity is highest in major markets during active sessions — for example, EUR/USD or gold during the London–New York overlap — and lowest around daily rollover, on holidays, at the weekly open, and in the minutes around big news (see Market sessions and liquidity cycles).

Practical ways to reduce costs

• Trade liquid instruments during their active session.
• Avoid opening trades in the few minutes before and after high-impact news unless your strategy is built for it.
• Use limit orders for entries when you're not in a hurry.
• Choose the account type that fits how often you trade.
• Log your fills. Compare your intended entry and stop with what you actually got.

Common beginner mistakes

• Not knowing the pip value of the position they've just opened.
• Comparing brokers on spread alone, ignoring commission and swap.
• Holding positions overnight without checking the swap rate.
• Blaming the broker for slippage that happened during a news spike or a weekend gap.
• Scalping small targets where costs consume a large share of every winner.

Key terms

Practice

1. Find your broker's contract specifications for EUR/USD and XAU/USD: contract size, typical spread, commission, and swap long/short.
2. Calculate the total cost of one 1-lot round trip on each instrument.
3. Pick a typical target for your style (for example 30 pips). What percentage of that target is your total cost?
4. Review your last five demo trades: compare the price you intended with the price you got. Record any slippage.

Quick recap

• A pip is usually 0.0001 (0.01 for JPY pairs); a standard lot of EUR/USD is worth about $10 per pip.
• Spread cost = spread × pip value × lots — paid on every trade.
• Total cost includes spread, commission, and swap, plus slippage when it happens.
• Market and stop orders can slip; limit orders cannot slip against you but may not fill.
• High liquidity means lower costs — trade liquid markets in their active hours.