An order that can be filled partly rather than in its entirety. In other words, such an order involves the execution of part, but not all, of a trade at the desired price. Partial orders are used with limit orders, as execution of such order will occur only when the price is within a pre-defined range, while it may only remain in the range for a volume not enough to fill the entire order in one execution. By default, limit orders usually comes with a partial fill setting.

If the entire size of an order is to be filled in one execution at a specified price or better, a limit order, rather than be partially filled, can be modified (using order modifications). A trader getting a partial fill on a volatile security would better cancel the remaining portion and wait for the price to move in a desired direction.

Unlike a partial order (or a limit order), a market order or a stop order will continue to fill once the price enters, and remains in, the range until the entire order amount is filled.

This order is also known as a partial fill.