Fill
The actual execution of an order, at the price and quantity you really received.
Also called: execution · filled
In plain language
A fill is the moment an order stops being an intention and becomes a position. The fill price — not the price you were watching — is what all of your math runs on.
A single order can produce several fills at different prices as it consumes multiple levels of the book. Your effective entry is the volume-weighted average of them.
Reviewing fills against intended prices is the cheapest audit in trading. Persistent gaps between the two point at order type, timing, or size problems.
Why it matters
Recalculating your risk from the real fill, not the planned entry, is what keeps your actual exposure equal to the exposure you designed.
Common mistakes
- Journaling planned prices instead of fill prices, which hides the real cost of execution.
- Leaving the stop at its planned distance from a fill that came in far away from the intended entry.
Keep exploring
These concepts are connected. Understanding one usually makes the next one easier.
When only part of your order executes and the rest stays open or is canceled.
The difference between the price you expected and the price you actually got.
The price at which you open a position.
The live list of all resting buy and sell orders at each price level.
A record of every trade, including the reasoning behind it and the result.