Definition
IOC Order (Immediate or Cancel)
An Immediate or Cancel order executes immediately against available orders to whatever extent possible, and any unfilled portion is cancelled instantly rather than resting in the order book.
On Indian exchanges, an IOC order is useful when a trader wants to grab whatever liquidity is available at or better than a limit price right now, without leaving a resting order that signals intent. It can result in a partial fill, with the remainder cancelled at once.
IOC is favoured by algos and active traders who do not want exposure to a resting order being picked off as conditions change. It contrasts with a normal day order that rests until filled or end of day, and with Fill or Kill, which demands the entire quantity be filled immediately or none at all.
Related terms
- Fill or Kill (FOK) OrderA Fill or Kill order must be executed in its entirety immediately, or the whole order is cancelled; partial fills are not permitted.
- Day OrderA day order is valid only for the trading session in which it is placed; if it is not executed by the close, it is automatically cancelled and does not carry over to the next day.
- Limit OrderA limit order specifies the maximum price a buyer will pay or the minimum a seller will accept, executing only at that price or better and resting in the order book until it can be filled.
Plain-English explainer from The Dispatch Investors Encyclopedia. General information, not financial advice.