Trailing Stop Loss Explained: How It Works and When to Use It

What Is a Trailing Stop Loss?

A trailing stop loss is an order type that attempts to lock in gains while a position moves favourably, then triggers an order to close the position if the market reverses by a specified amount (though execution and price are not guaranteed).

Unlike a fixed stop loss, it adjusts automatically as the price moves in your favour. This guide explains how trailing stops work, compares them to other order types and outlines the risks you should understand before using them.

Trading involves the risk of financial loss. Order types such as trailing stops do not guarantee execution at your specified price, particularly during volatile conditions or when markets gap. The information below is for educational purposes only and does not constitute personal investment advice.

Trailing Stop Loss Meaning and Definition

The meaning of a trailing stop loss is centred on the word ‘trailing’. Rather than setting a static exit point, you are setting a dynamic one. The stop level trails the highest price reached since you opened the position for a long trade, or the lowest price for a short trade.

For example, if you buy a share at 100p and set a trailing stop at 10p below the market price, your initial stop sits at 90p. If the share rises to 120p, your stop automatically moves to 110p. Should the share then fall to 110p or below, the order triggers.

How Does a Trailing Stop Loss Work?

A trailing stop loss works by continuously recalculating its trigger level based on the most favourable price achieved during the life of the trade. The mechanism varies slightly depending on whether you set the trailing distance as a fixed amount in points or pence, or as a percentage of the current price.

When you open a long position and apply a trailing stop:

• The stop initially sits at a set distance below your entry price

• As the market price rises, the stop rises by the same amount

• If the market price falls, the stop remains stationary

• The order triggers when the market price touches or crosses the stop level

The reverse applies for short positions. The stop trails above the market price and moves downward as the price falls. If the market price rises, the stop remains stationary. If the price touches or rises above the stop level, the order triggers.

A Step-by-Step Example

Consider this hypothetical scenario. You buy 100 shares of Company X at 500p per share. You set a trailing stop loss at 30p below the market price.

In this example, the trailing stop captured some of the upward movement. However, had the price gapped down overnight to 510p, the order would likely have executed at approximately 510p, not 530p. This gap risk is a key limitation.

This example is purely illustrative. Past performance and hypothetical scenarios do not indicate future results.

Trailing Stop Loss vs Standard Stop Loss

A standard stop-loss order sits at a fixed price level until you manually adjust it or the order executes. A trailing stop loss moves automatically with favourable price action.

Both order types share a common limitation: neither guarantees execution at the specified price. In fast-moving or gapping markets, both may execute at a materially different price than expected.

A stop-loss order, whether trailing or fixed, becomes a market order once triggered. Execution then occurs at the best available price, which may differ from your stop level.

Trailing Stop Loss vs Stop-Limit Order

A stop-limit order combines features of stop and limit orders. When the stop price is reached, instead of becoming a market order, it becomes a limit order. This means execution only occurs at the limit price or better. 

Trailing Stop Loss vs Stop-Limit Orders:

A stop-limit order may provide more control over execution price but introduces the risk that your order never fills if the market moves past your limit. A trailing stop, once triggered, will execute at prevailing market prices, increasing fill probability but potentially at a worse price than anticipated.

Neither order type eliminates risk. Each involves trade-offs between execution certainty and price certainty.

Potential Benefits of Trailing Stop Orders

Trailing stop loss orders may offer certain advantages depending on your trading approach and objectives. These benefits come with corresponding limitations.

• Automated adjustment: The stop level moves without requiring manual intervention.

• Potential to capture gains: By following favourable price movement, a trailing stop may help close a position while some profit remains.

• Defined exit parameters: Setting a trailing distance provides predetermined exit criteria.

• Flexibility: Trailing stops can be set as fixed amounts or percentages, allowing adaptation to different instruments and volatility levels.

These potential benefits do not guarantee profitable outcomes. A trailing stop set too tight may trigger prematurely during normal market fluctuations. One set too wide may give back substantial gains before triggering.

Risks and Limitations to Consider

Trailing stop losses carry material risks that you should understand before use.

Gap risk: Markets can open significantly higher or lower than the previous close. If a gap occurs, your trailing stop may execute at a price far beyond your intended level. Overnight gaps in shares or weekend gaps in forex are common examples.

Slippage: Even in continuous trading, rapid price movements may cause execution at a price different from your stop level. High volatility increases slippage risk.

Whipsaw: In choppy or volatile markets, prices may trigger your trailing stop during a temporary dip, only to resume the original trend immediately afterward.

No guarantee of profits: A trailing stop does not guarantee that you will exit with a profit. If the price never moves in your favour after entry, your trailing stop remains at its initial level and may execute at a loss.

False sense of security: Trailing stops do not eliminate risk. They are tools for exit management, not profit assurance.

When Might a Trailing Stop Loss Be Appropriate?

Trailing stops may suit certain trading styles and market conditions better than others.

Trending markets: When prices move directionally with fewer sharp reversals, a trailing stop may follow the trend effectively. In ranging or choppy markets, the same stop may trigger frequently during normal fluctuations.

Longer holding periods: Traders holding positions over days or weeks may find trailing stops useful for managing exits without constant monitoring.

Defined risk parameters: If you prefer predetermined exit criteria over discretionary decision-making, a trailing stop provides a systematic approach.

Situations where trailing stops may be less suitable:

• Very short-term trading where rapid price swings are common

• Highly volatile instruments prone to large intraday moves

• Markets with frequent gaps, such as individual shares around earnings announcements

No order type suits all market conditions. The appropriateness of a trailing stop depends on the specific instrument, market environment, and your individual circumstances and risk tolerance.

How to Set a Trailing Stop Loss: Key Considerations

Setting a trailing stop involves balancing competing priorities. A tighter stop provides closer protection but may trigger prematurely. A wider stop gives more room for price fluctuation but may return more of your gains if the market reverses.

Distance selection: Consider the typical price range or volatility of the asset. For example, a share that commonly moves around 5% intraday might trigger a 2% trailing stop during the noise of normal trading. Therefore, a 2% trailing stop may be seen as too tight relative to typical intraday fluctuations.

Fixed amount vs percentage: A fixed point or pence distance remains constant regardless of price level. A percentage-based distance adjusts proportionally as the price changes.

Time of day: Some traders avoid setting trailing stops around market open or close when volatility often increases.

Instrument characteristics: Currency pairs trade nearly continuously, but gaps can still occur (for example over weekends or during major events). Individual shares may gap significantly on news or earnings.

Review and adjustment: Even with automatic trailing, a periodic review of your stop distance relative to current market conditions may be prudent.

Summary

A trailing stop loss is an order type designed to follow favourable price movement while providing an automatic exit if the market reverses. Unlike a standard stop loss, it adjusts dynamically rather than remaining at a fixed level.

Key points to remember:

• The trailing stop only moves in one direction, following gains.

• Once triggered, it becomes a market order with no guaranteed execution price.

• Gap risk, slippage and whipsaw remain material concerns.

• Trailing stops suit some market conditions and trading styles better than others.

• They do not eliminate risk or guarantee profitable outcomes.

Understanding how trailing stop losses work is essential before incorporating this order type into your trading. Like any tool, its effectiveness depends on appropriate use, realistic expectations and clear awareness of its limitations.

This guide provides general information for educational purposes. It does not constitute personal investment advice. Trading involves the risk of loss, and you should ensure any order types you use align with your individual circumstances and risk tolerance.