Does a stop loss work after hours?
Stop loss orders are generally only executed during regular market hours, which can pose a problem for investors trading securities that gap down or up overnight. A significant drop in a stock’s price could trigger a good-til-canceled stop order that is actually executed at a much lower price than that specified in the stop order. To avoid this problem, you can place a stop-limit order, ensuring the trade will only be executed at a specified price or better.