Partial Fills: When Only Part of Your Order Trades
An order does not always trade in one go. It can fill in pieces, at different prices, or only partly.
Why this matters for beginners
Knowing order statuses tells you what you actually own and what is still just an instruction. This is general education, not personal advice.
Main explanation
After you place an order it is open. As matching sellers or buyers appear, pieces of it execute.
Each filled piece is a real trade. The unfilled remainder follows the order's duration, for example it expires at the close for a day order.
Your average price across fills is your real cost per share.
Settlement completes the filled trades, typically one business day later in many markets.
Example using a real company
A limit order for 500 shares of a small company might fill 300 shares today and expire with 200 unfilled.
- →200 @ 29.98 and 100 @ 30.00 average about 29.987.
Common beginner mistakes
- ✕Assuming an order is all or nothing.
- ✕Forgetting about an open remainder that may fill later.
Key terms
- Partial fill
- Only part of an order has executed.
- Day order
- An order that expires at the end of the trading session.
- Average price
- Total cost of all fills divided by shares filled.
Key takeaways
- 01Filled pieces are real trades.
- 02Check order status and duration after placing an order.
Check yourself
- 01A day order fills 300 of 500 shares by the close. What happens to the other 200?
- 02Which order type is most likely to fill only partly?
Try the concept on a real company
Open a smaller company in the Analyzer and consider how easily large orders in it might fill.
Educational examples only. Not buy or sell recommendations.