Glossary
Slippage
Trading
Slippage is the difference between the price a trader expects on an order and the price at which it actually fills.
Slippage appears when liquidity cannot absorb an order at the quoted price — around news releases, at the open, and on stop orders in fast markets. It can be negative or positive.
Limit orders eliminate price slippage but risk not filling at all; market and stop orders guarantee execution but not price. Measuring average slippage per strategy matters most for scalping, where it can exceed the spread.