Day orders, Good-til-Cancelled (GTC) orders, and Immediate-or-Cancel (IOC) orders represent timing instructions for an order and may be applied to either market or limit orders. Unless an investor specifies a time frame for the expiration of an order, orders to buy and sell a stock are Day orders, meaning they are good only during that trading day. A GTC order is an order to buy or sell a stock that lasts until the order is completed or canceled.
Brokerage firms typically limit the length of time an investor can leave a GTC order open. This period may vary from broker to broker. Investors should contact their brokerage firms to determine what time limit would apply to GTC orders. An IOC order is an order to buy or sell a stock that must be executed immediately. Any portion of the order that cannot be filled immediately will be canceled.
Two other common special order types are Fill-Or-Kill (FOK) and All-Or-None (AON) orders. A FOK order is an order to buy or sell a stock that must be executed immediately in its entirety; otherwise, the entire order will be canceled (i.e., no partial execution of the order is allowed). An AON order is an order to buy or sell a stock that must be executed in its entirety, or not executed at all. However, unlike the FOK orders, AON orders that cannot be executed immediately remain active until they are executed or canceled.