Slippage Explained: How and Why It Occurs

Introduction

Slippage is a common part of trading that can affect your entry price, exit price, and overall trade outcome. It happens when the price at which you expect your order to be filled differs from the price at which it is actually executed. Understanding what is slippage in trading, why it happens, and how to manage it can help you make better decisions, particularly when trading during fast moving markets.

What Is Slippage in Trading?

Slippage is the difference between the price you expect when placing an order and the actual execution price. It can happen with both buy and sell orders and is most common when markets are moving quickly or when there is limited liquidity available at your desired price.

For example, imagine you place a market order to buy EUR/USD at 1.10000. By the time your order reaches the market and is executed, the available price may have moved to 1.10030. You have therefore experienced 3 pips of slippage.

Slippage does not always work against you. If your order is executed at a better price than expected, you experience positive slippage. If you receive a worse price, it is negative slippage.

Positive vs Negative Slippage

The direction of the price movement determines whether slippage benefits or hurts your trade.

Positive slippage occurs when you receive a better execution price than the one you expected. For a buy order, this could mean being filled slightly below your requested price. For a sell order, it could mean receiving a slightly higher price.

Negative slippage occurs when the actual execution price is less favourable. A buy order may be filled above the expected price, while a sell order may be filled below it.

Neither type necessarily indicates a problem with the trading platform or broker. Price can move between order placement and execution, particularly when market conditions are changing quickly.

What Causes Slippage?

Several factors can contribute to slippage. The most common ones are related to market conditions and the way an order is executed.

Volatility

Fast moving markets create more opportunities for slippage because prices can change significantly within a very short period. Major economic announcements, unexpected news, and sharp market reactions can all increase the possibility of a different execution price.

This is one reason traders should be particularly careful around major news releases. A setup that looks attractive before an announcement can behave very differently once volatility increases.

Liquidity

Liquidity refers to how much buying and selling activity is available around different price levels. When there is sufficient liquidity, orders can generally be matched more easily near the requested price.

When liquidity is thin, there may not be enough available orders at your preferred level. Your order may then be matched at the next available price, creating slippage.

Understanding volume and liquidity can therefore be useful when assessing potential execution conditions.

Also Read: Volume Profile Trading

Execution Delay

There can be a short period between submitting an order and receiving an execution. Even a small delay can matter when the market is moving quickly.

This does not necessarily mean the delay is caused by a single technical issue. Market conditions, connectivity, order routing, and available liquidity can all influence the final execution.

Order Type

The type of order you use also affects how much control you have over execution.

A market order prioritises execution, meaning you are generally asking for the order to be filled at the best available price rather than specifying an exact price.

A limit order specifies the maximum price you are willing to pay when buying or the minimum price you are willing to accept when selling. This provides greater price control, although the order may not be filled if the market does not reach your specified level.

Slippage in Forex vs Futures vs Crypto

Slippage can occur across different markets, but the conditions behind it can vary.

In forex, major economic announcements and periods of reduced liquidity can increase execution differences. Futures can experience fast moves around economic data and market openings, while crypto can experience substantial price changes when market activity suddenly increases or liquidity becomes fragmented across exchanges.

Also Read: Slippage in Forex

The important point is that slippage is not limited to one asset class. Traders should understand the execution characteristics of the market they are trading rather than assuming that an execution experience in one market will be identical in another.

How to Calculate Slippage

Calculating slippage is straightforward. You compare the expected execution price with the actual execution price.

For example, suppose you intended to buy EUR/USD at 1.10000 but your order was filled at 1.10030.

Slippage = Actual execution price − Expected execution price

In this example:

1.10030 − 1.10000 = 0.00030

For EUR/USD, that represents 3 pips of slippage.

For other markets, the calculation depends on the instrument's tick or point value. Futures traders, for example, should consider the contract's minimum tick size and tick value when assessing the monetary impact of slippage.

Keeping a record of expected and actual execution prices in your [trading journal] can help you identify whether slippage is occasional or becoming a recurring issue in your trading.

How to Avoid Slippage in Trading

You cannot completely eliminate slippage, but you can take steps to reduce its frequency and impact.

Avoid Trading During Extreme Volatility

If your strategy does not specifically depend on news trading, consider avoiding periods when major economic announcements are expected. Sudden price movements can make execution less predictable.

Consider Your Order Size

Large orders can be more difficult to execute at a single price, particularly when available liquidity is limited. Your position size should therefore make sense for both your account and the market conditions.

Use Limit Orders When Price Control Matters

Limit orders can help you control the maximum or minimum price at which you are willing to trade. However, remember that greater price control can come with the possibility of the order not being filled.

Trade When Liquidity Is Strong

Periods of stronger market participation generally provide more available liquidity. Understanding the normal trading hours and liquidity conditions of the market you trade can help you choose better execution windows.

Keep Risk Management in Place

Slippage becomes more significant when a trade is already close to its maximum acceptable risk. Good [risk management] should account for the possibility that actual execution may differ slightly from the planned price.

Slippage on a Prop Firm Account

Slippage is particularly important when trading a prop firm account because the account's trading rules may include specific daily or maximum loss limits.

A trader might plan a trade around a precise entry and stop loss, but if the market moves rapidly, the actual execution can differ from the planned price. This can increase the realised loss on a position.

That is why prop traders should avoid building a strategy around the assumption that every order will be filled at the exact price visible on the chart.

This is also where maintaining a detailed trading journal can help. Recording your entry price, expected execution, actual fill, market conditions, and the reason for the trade gives you useful data to review later. Over time, you may notice that certain instruments, sessions, or market conditions consistently produce more slippage.

For traders preparing for a prop firm challenge, this can be particularly useful because execution costs should be considered alongside position sizing, drawdown, and other account rules.

Final Thoughts

Slippage is simply a difference between the price you expect and the price at which your trade is actually executed. It can be positive or negative and is influenced by volatility, liquidity, execution delay, and order type.

The goal is not to eliminate slippage completely. Instead, understand what is slippage in trading, recognise when it is more likely to occur, and build your trading process around realistic execution.

If you want to learn how to avoid slippage in trading, start by paying attention to market conditions, position size, liquidity, order types, and execution patterns. Combined with sound risk management and consistent journaling, these habits can help keep slippage from becoming an unnecessary source of trading losses.