Limit Orders

To avoid buying or selling a stock at a price higher or lower than you wanted, you need to place a limit order rather than a market order. A limit order is an order to buy or sell a security at a specific price. A buy limit order can only be executed at the limit price or lower, and a sell limit order can only be executed at the limit price or higher. When you place a market order, you can't control the price at which your order will be filled.

Remember that your limit order may never be executed because the market price may quickly surpass your limit before your order can be filled. But by using a limit order you also protect yourself from buying the stock at too high a price. Some firms may charge you more for executing a limit order than a market order.

For more information on the different types of orders you can place when you buy or sell a stock, please read "Brokerage Orders" in our Fast Answers databank.

Source: http://www.sec.gov/answers/limit.htm