"AON" is a type of restricted order where the entire order must be filled at one time or nothing will be filled at all. If you do not specify your order as "All Or None" when placing a limit order, there is a possibility that your order will be filled partially. Full commission fees and charges apply for each partial fill, except those transacted within the same business day.
Requirement that none of an order be executed unless all of it can be executed at the specified price.
Directs the broker to attempt to fill the entire amount of the order or none of it during the time limit you specify. This differs from "Fill or Kill" orders because "All or None" orders do not require immediate execution. Only applicable to Limit Orders.