Slippage
Order Types & Execution
Slippage is the difference between the expected price of a trade and the price at which it is actually executed, common in fast or illiquid markets.
What is slippage?
Slippage happens when the price at which a trade is actually filled differs from the price a trader expected when they placed the order. It’s most closely associated with market orders, which prioritize speed over an exact price, but it can also affect stop orders once they’re triggered and converted into a market execution.
Why slippage happens
Prices in the market update continuously, and even a fraction of a second between clicking “buy” and the broker actually filling the order can be enough for the price to move. Slippage tends to be larger:
- Around major news releases or economic data, when prices can jump sharply.
- In thinly traded instruments or during low-liquidity hours, when fewer orders are available at each price level.
- During fast-moving breakouts, when a triggered stop order chases a price that keeps running away from it.
Worked example
Suppose a trader places a market buy order on EUR/USD while it’s quoted at 1.0850. In a calm market, the order likely fills at or very close to 1.0850. But if a surprise central-bank announcement hits at that exact moment, the order might instead fill at 1.0856 — six pips of negative slippage. Slippage can also work in a trader’s favor: if price briefly improves during that same window, the fill could land at a better price than expected, which is called positive slippage.
Slippage vs. requote
Some brokers handle a moved price by filling the order at the new price automatically (slippage); others, particularly those using instant execution, instead pause and ask the trader to accept or reject the new price — this is called a requote rather than slippage.
Why it matters
Slippage is a real, if often small, trading cost that adds up over many trades, especially for active or news-based traders. A broker’s execution quality — how consistently it fills orders close to the quoted price — is one of the more practical, checkable differences between brokers, and independent reviews or a broker’s own execution statistics can help gauge it beyond marketing claims.
Trading carries a high level of risk and may not be suitable for all investors.