Partial Fill

A partial fill occurs when only a portion of an investor's buy or sell order is executed — rather than the entire quantity specified in the order — because insufficient matching orders exist on the other side of the trade at the specified price or within the acceptable price range. For example, if an investor places a limit order to buy 1,000 shares of a stock at ₹500 but only 600 shares are available at that price in the order book, the order will be partially filled for 600 shares — leaving the remaining 400-share balance as an open order waiting for additional matching supply. In Indian equity markets on NSE and BSE, partial fills are common for limit orders in less liquid mid-cap and small-cap stocks, or for large institutional orders that exceed the available depth at any single price level. Most online trading platforms and mobile apps display the filled quantity and remaining open quantity clearly in the order book section, allowing investors to monitor and manage partial fills in real time. Investors placing orders in illiquid stocks should be particularly mindful of partial fill risk, as it can result in unintended partial exposure and higher average transaction costs if the remaining balance is filled at less favourable prices subsequently.