**Educational Post**

**All or None Order (AON)**

An All or None order (AON) is a financial exchange order to buy or sell a specific asset volume at a predetermined price. Unlike other order types, such as market or limit orders, an AON order carries a specific instruction regarding its execution.

As its name implies, an AON order must be filled in its entirety or not at all. This prevents partial order fulfillment, ensuring the buyer or seller a fixed execution price for the entire volume.

AON orders find application in algorithmic trading, where they serve as a tool to assess market directional trends and mitigate partial fill scenarios. These scenarios may arise in highly volatile markets with low volumes, such as during flash crash events.