An order is said to be a partial fill when it trades only some part of its total volume. It is a situation in which a broker order can only be fulfilled partially within the given time frame. When a broker is able to purchase only a part of the desired lot of shares either at or below the limit order price, it is known as a partial fill.
How do partial fill orders work?
Depending on market movements or new offers becoming available, there is a possibility that an order remains partially fulfilled. It is a common phenomenon that an order may be completed only as multiple partial fills over a long period of time. Brokerages may charge the same fees for partial fills as for fully-completed orders, which turns out to be expensive when an order can only be completed in multiple partial fills.
