Home » Fill Ratio

Fill Ratio

« Back to Glossary Index

The fill ratio measures the number of successfully filled orders as a fraction of the total number of orders placed, normally stated as a percentage.

The efficiency and success of executing orders play a crucial role in determining the performance of a trading strategy.

One metric that helps traders assess the effectiveness of their order execution is the fill ratio.

Let’s explore the concept of fill ratio, the factors that influence it, and its importance in trading.

Understanding Fill Ratio

The fill ratio refers to the percentage of an investor’s or trader’s order that is executed or “filled” in the market.

It serves as an indicator of how effectively and successfully an order has been executed, especially in scenarios where large orders are divided into smaller parts to minimize market impact or manage risk.

A high fill ratio signifies that most of the order was executed, while a low fill ratio indicates that only a small portion was filled.

Calculating Fill Ratio

The fill ratio is calculated by dividing the total number of shares (or contracts) executed by the original order size, and then multiplying the result by 100 to express it as a percentage:

Fill Ratio (%) = (Total Shares Filled / Original Order Size) * 100

A higher fill ratio is generally preferable, as it implies that a larger portion of the order was executed at the desired price levels, potentially leading to better overall trade performance.

Factors Influencing Fill Ratio

Several factors can impact the fill ratio:

1. Market liquidity: Highly liquid markets with numerous buyers and sellers usually have a positive effect on the fill ratio, as there are more opportunities for orders to be executed.
2. Order size: Large orders may result in lower fill ratios, as they can be more challenging to execute without affecting market prices.
3. Order type: Different order types, such as market orders or limit orders, can influence the fill ratio. For instance, market orders might have a higher fill ratio but may also result in unfavorable execution prices.
4. Trading strategy: Algorithmic trading strategies and smart order routing systems often aim to optimize the fill ratio by seeking the best possible execution venues and strategies for a given order.

The Importance of Fill Ratio in Trading and Investing

Understanding and monitoring the fill ratio is essential for traders as it can impact the cost of executing trades and the overall performance of their trading strategies.

A higher fill ratio typically indicates efficient order execution, which can lead to better trade performance and more favorable outcomes.

Additionally, the fill ratio can be used to assess the effectiveness of trading algorithms or brokers, as it provides a benchmark to compare different execution strategies and service providers.