What Is IOC (in Trading)?

An IOC (Immediate or Cancel) Order is a trade instruction designed to execute as much of your order as possible immediately. Any portion of the order that isn’t filled right away is canceled.

How It Works

• Partial Execution: If part of the order can be matched right away, that portion is executed, and the rest is canceled.
• No Waiting: If no part of the order can be executed immediately, the entire order is canceled on the spot.
• Purpose: It’s often used in fast-moving markets or when traders want instant results without lingering orders.

Example

You want to buy 1,000 shares of a stock at $50 per share using an IOC order:

• If 700 shares are available at $50, those are immediately purchased, and the remaining 300 shares are canceled.
• If no shares are available at $50, the entire order is canceled.

Why It’s Useful

• Speed Over Completeness: Ideal for traders who prioritize quick execution over filling the full order.
• Avoids Delays: Ensures no portion of the order remains active after the initial attempt.

Key Takeaways

An IOC order is all about speed—either execute what you can right away or cancel the rest. It’s a no-nonsense option for traders looking to act fast in dynamic markets.