Fill or Kill (FOK)
Order TypesAn order that must be filled immediately and in its entirety, or it is cancelled completely. There is no partial fill.
What Is a Fill or Kill Order?
A Fill or Kill (FOK) order demands immediate execution of the entire order quantity at the specified price or better. If the full quantity cannot be filled instantly, the entire order is cancelled. There is no waiting and no partial fills. It is an all-or-nothing instruction with a time constraint of essentially zero.
FOK vs. Other Order Types
FOK orders differ from Immediate or Cancel (IOC) (IOC) orders, which allow partial fills. With IOC, if you order 10 Lots and only 7 are available, you get 7 lots and the remaining 3 are cancelled. With FOK, you get nothing unless all 10 lots are available. FOK also differs from All or None (AON) (AON) orders, which do not require immediate execution.
FOK Orders in Forex
FOK orders are rarely used by retail forex traders because standard lot sizes (1 micro to a few standard lots) are easily filled in the liquid forex market. They are more relevant for institutional traders dealing in very large sizes where partial fills could disrupt their strategy. Most retail trading platforms do not offer FOK as an order option.
Related Terms
Good Till Cancelled (GTC)
A pending order that remains active until it is either filled or manually cancelled by the trader. There is no expiration date.
Immediate or Cancel (IOC)
An order that must be filled immediately. Any portion not filled instantly is cancelled. Unlike fill-or-kill, partial fills are accepted.
All or None (AON)
An order that must be filled entirely or not at all, but unlike fill-or-kill, it does not require immediate execution. The order can wait for full liquidity.