Slippage explained: why your fill price differs from your click

By Ken Chigbo, Founder, KenMacro. Published 2026-05-12.

What is slippage?

Slippage is the gap between displayed price at the moment of order submission and the actual fill price. The gap arises because price moves continuously, while order submission and confirmation take milliseconds to seconds. Slippage can be positive (fill better than displayed) or negative (fill worse than displayed). On ECN and STP venues, orders fill against the next available liquidity at the time of execution, which produces slippage that follows the underlying market move. On market-maker venues, slippage tends to skew negative because the broker decides whether to honour a stale quote or to requote.

How traders use slippage

Professional traders measure slippage as a documented venue metric, not an anecdote. The desk benchmarks slippage on each reviewed broker under controlled conditions: 100 round-turn market orders on EUR/USD during the London session, recorded fill price versus displayed price at submission, average and worst-case slippage tabulated. A well-conducted ECN raw-spread account typically shows 0.0 to 0.2 pips of average slippage during liquid hours with symmetric distribution. A poorly conducted venue shows 0.5 to 2.0 pips of average slippage with negative skew. Slippage during news prints can run 5 to 30 pips on any venue and is a normal market cost. Trading strategy should account for documented average slippage as a fixed cost per trade.

Worked example with slippage

Consider a EUR/USD trader who submits 100 market orders during the London session, each at a displayed price of 1.08500. On a well-conducted ECN, fills average 1.08501 (0.1 pips negative slippage) with a symmetric range of 1.08498 to 1.08504. On a poorly conducted market-maker venue, fills average 1.08507 (0.7 pips negative slippage) with an asymmetric range of 1.08501 to 1.08520. Over 100 trades, the slippage cost differential is 60 pips, which on one-lot positions equals roughly 600 US dollars of pure venue cost. Slippage is the silent tax on poorly conducted execution.

Open a Vantage raw-spread account

Frequently asked

Is slippage normal in forex trading?

Slippage during news prints and low-liquidity windows is normal on every forex venue, including the best ECN and STP brokers. Average slippage of 0.0 to 0.3 pips on liquid pairs during liquid hours is normal. Average slippage above 0.5 pips on liquid pairs during liquid hours suggests poor venue conduct and warrants a switch.

How do I measure slippage on my broker?

Slippage is measured by recording displayed price at the moment of market-order submission and comparing to actual fill price, across at least 50 to 100 orders on a single pair during controlled session windows. Aggregate the differences, calculate average and worst-case. Compare against published broker benchmarks like the KenMacro broker reviews tabulation.

Can slippage be positive?

Positive slippage (fill better than displayed) is normal on well-conducted ECN venues and reflects the underlying market moving in the trader’s favour during the milliseconds between submission and execution. A venue showing strictly negative slippage (every fill worse) is signalling that the dealing desk is filtering fills selectively against the client.

Educational analysis only. Past performance does not guarantee future results. Manage risk against your own portfolio.