All or None (AON) Definition
Similar to the well-known Fill or Kill order policy, All or None is less common in Forex and CFD trading. An order using the All or None Time in Force will only be filled if the entire amount desired by the trader can be filled. If it can’t be filled completely, then the order will rest until it can.
Usually, this policy would usually not be used with Market Orders. This is because there is no protection from price movements unless an expiry can be assigned. However, usually, only one Time in Force can be applied to an order. This means that Good ‘til Date cannot be used with All or None. To prevent this situation most brokers who offer this setting would cancel all AON Market Orders at the end of a trading session. As we all know, the markets can be volatile and large price movements can occur in a single trading session.
More commonly this order type would be used with Limit Orders or Stop Orders. This is because these order types specify price conditions. Currently, cTrader does not support this Time in Force and it is unlikely the platform ever will as it’s not very popular in Forex trading.