All-or-none (AON) orders are most commonly used in equity markets, particularly for trading large blocks of stocks. These orders ensure that a trader’s full order is executed at a specified price or not executed at all. This condition is especially useful when dealing with illiquid stocks or when a trader wants to avoid partial fills, which can distort the average execution price or leave an incomplete position.

In over-the-counter (OTC) markets, where trades are negotiated directly between parties, AON orders are also more prevalent. These markets often involve larger and less frequent trades, making the all-or-none condition valuable for institutional investors seeking to maintain control over large transactions.

While AON orders can technically be used in bond markets and some commodity trades, they are less common there due to different trading structures and execution priorities. In contrast, forex markets typically do not support AON orders because of their high liquidity and decentralised structure.

Not all exchanges or brokers offer AON order functionality. Some have phased it out due to inefficiencies or the rise of algorithmic trading. Still, AON orders remain relevant for traders who prioritise complete execution over speed, especially in lower-volume stocks or complex trading strategies.