What Is Slippage and How Does It Affect the Execution of a Stop-Loss Order?

Slippage is the difference between the expected price of a trade and the price at which the trade is actually executed. In volatile or illiquid markets, a stop-loss order, which often converts to a market order, may be filled at a significantly worse price than the stop price.

This results in larger losses than anticipated, potentially still triggering a margin call.