Execution & Slippage Explained
Key takeaways
- Slippage is the difference between reference price and fill price. It can be positive, zero, or negative.
- Execution quality is about distribution over time, not any single fill.
- Verifiable context (receipts, methodology) matters more than speed claims.
What is execution?
Execution is the process of filling your order at a price. When you click "buy" or "sell," your order travels from your platform to the broker's server, where it's matched and filled. The quality of that process (how fast, how accurately, and how fairly it happens) is what we mean by execution quality.
How a trade gets filled
- You send an order from MT5 with a requested price
- The order reaches the server. The time this takes depends on your latency.
- The server matches the order against available liquidity at the current market price
- You receive a fill. It may be at, above, or below your requested price.
The difference between your requested price and your fill price is slippage.
Understanding slippage
Slippage is not inherently good or bad. It's a natural result of markets moving in real time. What matters is the distribution:
- Positive slippage: The market moved in your favor. You got a better price than you asked for.
- Zero slippage: Filled at exactly the price you requested.
- Negative slippage: The market moved against you. You got a worse price than you asked for.
What to watch for
A fair execution environment should show a roughly balanced distribution of positive and negative slippage over time. If you consistently see only negative slippage, it may indicate that positive slippage is being captured by the broker rather than passed through to you.
Execution speed
Execution speed is how quickly your order is filled after it reaches the server. Faster execution means less time for the market to move between your order and your fill.
- p50 (median): The typical execution speed for most orders
- p90: Captures execution speed during busier or more complex order flow
Execution speed is affected by market conditions, order size, and the liquidity available at your requested price.
Reject rate
A rejection happens when your order can't be filled, usually because the price has moved too far from your requested level. A low reject rate means most of your orders are getting through.
High reject rates can indicate aggressive last-look practices or insufficient liquidity.
What is last look?
Last look is a practice where liquidity providers can reject or delay an order after seeing it. Some brokers pass through last-look rejections as requotes. Understanding whether your broker uses last-look LP flow is important for evaluating execution quality.
How Milton Prime approaches execution
We believe in showing our work:
- Trade receipts break down every fill: reference price, fill price, slippage, spread at fill, and the surrounding tick window
- Transparency reports publish aggregate metrics so you can evaluate quality over time
- No hidden practices. What you see on the receipt is what happened.
We'd rather you evaluate our execution with data than take our word for it.
View a sample receipt | See the transparency report | Understand trading costs