What is partial order execution?

Partial execution happens when the market doesn’t have enough matching quantity at your price to fill your entire order in one go. For example, if you place a buy order for 1,000 shares at ₹250, and only 400 shares are available from sellers at that price at that moment, 400 shares get executed and the remaining 600 stay pending, waiting for more sellers to appear at ₹250 or better. The unfilled portion either fills later if the price stays available, gets cancelled by you manually, or expires at the end of the order’s validity period (commonly end of day for a regular order). Charges like brokerage can sometimes apply separately to each partial fill depending on the broker’s billing logic, so you check the contract note for the actual filled quantity and corresponding charges rather than assuming your full order size was billed.