Order fill

An order fill occurs when a broker successfully executes a trader's instruction to buy or sell a financial instrument. This involves matching the trader's order with available liquidity in the market. For instance, a market order to buy EUR/USD is filled when a seller at the current ask price is found, and the trade is completed. The fill price is the actual price at which the transaction is finalized.

For a retail trader, the order fill price is crucial as it directly impacts profitability. Slippage, where the fill price differs from the requested price, can occur, especially during volatile market conditions or with large order sizes. A positive slippage means a better price, while negative slippage means a worse price. Understanding fill quality helps assess broker execution, as consistent negative slippage can erode trading capital over time.