Sunk cost trap: stop-losses, averaging down and past losses
The sunk cost trap is the tendency to keep putting money, time, or effort into something because of what has already been spent – not because it still makes sense now.
In trading, this can show up as holding on to a losing position for longer than planned. The original reason for entering the trade may have weakened, the stop level may have been reached, or the market picture may have changed. Even so, closing the trade can feel difficult because it makes the loss feel final.
The issue is not simply that a trade is losing. Losses are part of trading. The sunk cost trap becomes a problem when the past cost of a trade starts to carry more weight than the current case for keeping it open.
Takeaways
- The sunk cost trap can lead traders to focus on what has already been lost, rather than what the trade looks like now.
- In trading, it can appear as holding losing positions past planned stop levels, averaging down without a clear reason, or continuing with a strategy mainly because of the time already spent on it.
- A useful question is: ‘Given what I know now, would I enter this position at this price?’
- Loss aversion can make the sunk cost trap harder to spot, because closing a losing trade can feel more uncomfortable than keeping it open.
- Pre-committed stop-loss orders can help reduce the pressure of making exit decisions in the moment, although standard stop-losses do not guarantee execution at the exact level in all market conditions. Guaranteed stop-loss orders incur a fee if activated.
- Risk management tools can support more consistent decision-making, but they do not remove the risks of trading. Contracts for difference (CFDs) are traded on margin, leverage amplifies both profits and losses.
- To understand why the sunk cost trap matters in trading, it helps to separate what has already happened from the decision that needs to be made now.
What is the sunk cost trap in trading?
The sunk cost trap – also called the sunk cost fallacy or sunk cost effect – happens when past costs affect a decision about the future. A sunk cost is something that has already been spent and cannot be recovered, regardless of what happens next.
In trading, a sunk cost might be:
- Money already lost on an open position.
- Time spent researching a trade.
- Effort invested in building a strategy.
- Emotional energy is already tied to being ‘right’ about the market.
These things may feel important, but they do not automatically improve the future outlook for the position.
Research by Hal Arkes and Catherine Blumer in 1985 helped show how the sunk cost effect can influence decisions (ScienceDirect, 1985). In one well-known example, people were more likely to continue with an option they had paid more for, even when another option appeared better (Coglode, accessed 23 June 2026). The past cost influenced the decision more than the future benefit (BehavioralEconomics.com, accessed 23 June 2026).
The psychology behind the sunk cost trap: why it happens
The sunk cost trap isn’t just about logic. In trading, loss, effort and hope can all make it harder to reassess a position clearly.
Loss aversion and the discomfort of closing a loss
One reason the sunk cost trap can feel powerful is loss aversion. Kahneman and Tversky’s prospect theory suggests that losses can feel more painful than similar-sized gains feel rewarding. For traders, this can make closing a losing position feel uncomfortable, even when the original reason for holding the trade has changed. Keeping the trade open can preserve the possibility of recovery, while closing it makes the loss clear and immediate. This does not mean holding is always wrong. A position may still have a valid case. But the decision can become less balanced if the main reason for holding is to avoid realising the loss.
Mental accounting and the ‘position account’
Richard Thaler’s work on mental accounting looked at how people separate money into different mental categories. In trading, an open position can become its own mental account. When the position is still open, the loss can feel unfinished. Closing the position can feel like closing that account in the red. That can make it tempting to keep the trade open, even when the current case for holding has weakened. This is why the entry price can become so influential. A trader may start thinking in terms of ‘getting back to breakeven’, rather than asking whether the position still fits the plan.
Escalation of commitment
Escalation of commitment happens when someone continues with a decision because they have already invested in it. In trading, this can mean adding to a losing position, increasing trade size after losses, or sticking with a strategy because it took a long time to build. The more time, money, or effort that has gone into something, the harder it can feel to step away from it. But more investment does not always mean a stronger future case.
The hope of recovery
The sunk cost trap often comes with a simple thought: the trade might come back. Sometimes, it might. Markets can reverse, and a losing position can recover. The risk is that this hope can become the main reason for holding. A trader may find a story for why almost any losing trade could recover, while paying less attention to whether the current evidence still supports the position. A balanced approach does not ignore the possibility of recovery. It weighs that possibility against the current trade plan, risk level, market conditions, and available capital.
The key is to judge the trade as it stands now. Ask whether you’d open the same position today, at the current price and risk. If not, past costs may be carrying too much weight.
Signs of the sunk cost trap in your trading
The sunk cost trap can be subtle. It may not feel emotional at the time, especially when you’ve already spent time analysing the market. But there are common signs to watch for:
- Holding losing positions past planned stop levels. Moving or ignoring a planned stop-loss can be a warning sign. It may be justified by fresh analysis, but if the main reason is avoiding a realised loss, the sunk cost trap may be influencing the decision.
- Averaging down into losing positions. Adding to a losing position can be part of a planned strategy, but it needs clear risk limits. If the goal is mainly to get back to breakeven, earlier losses may be driving the decision.
- Focusing too much on the entry price. Thinking ‘I’ll close when it gets back to where I bought’ can shift focus away from current market conditions. The entry price helps measure performance, but it doesn’t decide what happens next.
- Continuing a strategy because of time invested. Time spent learning, testing or refining a strategy can create useful knowledge. But it shouldn’t be the only reason to keep using a strategy that no longer fits current conditions or risk limits.
A simple check can help: would you make the same decision today, with the same price, risk and market conditions? If not, past effort or losses may be carrying too much weight.
How the sunk cost trap can affect your performance
The sunk cost trap can affect performance by allowing losses to grow beyond the level originally planned. A trade that was meant to be closed at a 1% loss may become a 3%, 5%, or 10% loss if the exit is delayed. In CFD trading, this matters because leverage can magnify both gains and losses. A delayed exit can therefore have a larger effect on account equity than it would in an unleveraged position. The sunk cost trap can also affect capital allocation. Money tied up in a position that no longer meets the trader’s criteria cannot be used elsewhere. This creates an opportunity cost as well as the direct loss on the open trade.
How to overcome the sunk cost trap in CFD trading
Overcoming the sunk cost trap starts with bringing each decision back to the present. The aim is to judge the trade on its current case, not the entry price, past effort or desire to recover.
- Step 1. Apply the forward-looking test Ask: ‘Would I enter this position now, at the current price?’ If not, reassess whether the trade still fits your plan, rather than focusing on the original entry price.
- Step 2. Use pre-committed stop-loss orders
A stop-loss order set at entry can reduce pressure when a position moves against you. It doesn’t remove risk, and standard stop-losses can be affected by slippage, but it can support more consistent decision-making. Guaranteed stop-loss orders incur a fee if activated. - Step 3. Keep position size separate from recovery goals
Size each trade based on the setup, account size and risk plan – not on previous losses. Increasing size to recover can make sunk cost thinking worse. - Step 4. Review process, not just outcome
Profit and loss don’t always show whether a decision was sound. Review whether the trade followed your plan, including entry criteria, stop level and exit.
The sunk cost trap is easier to manage when decisions are planned, consistent and reviewed honestly. By focusing on process over emotion, traders can reduce the pull of past losses and make clearer choices about what to do next.
Recovering from the sunk cost trap: what to do after
After a period of sunk cost behaviour – such as holding too long, moving stops, or adding to losing positions – it can help to review the actual cost of those decisions.
One practical method is to compare the planned exit with the final exit.
| Review point | Question to ask |
|---|---|
| Planned exit | Where was the original stop or exit level? |
| Actual exit | Where was the position eventually closed? |
| Difference | How much did the delay change the outcome? |
| Reason | What was the main reason for not following the plan? |
| Next step | What rule or tool could reduce the same pattern next time? |
This is not about blame. It is about making the cost of the behaviour visible, so the next decision can be based on clearer information.
For the next trading session, the reset can be simple:
- Return to the pre-trade plan.
- Set risk levels before entry.
- Avoid changing stops without a clear, pre-defined reason.
- Review decisions against the plan afterwards.
This is often more reliable than depending on willpower in a pressured moment.
Building long-term resilience against the sunk cost trap
Managing the sunk cost trap is not only about recognising it. It is also about building a trading process that makes it harder for the bias to take over.
That can include:
- Setting stop levels before entering a trade.
- Using position size limits.
- Avoiding unplanned averaging down.
- Setting daily loss limits that force a pause after a difficult session.
- Keeping a trading journal that records both planned and actual exits.
A trading journal can be especially useful because it creates a clear picture over time. The trader can review where delayed exits happen most often, which market conditions are involved, and what they were thinking at the time.
The sunk cost trap and risk management
From a risk management perspective, the sunk cost trap can be one reason planned losses become larger than expected. The stop-loss level is the tool; sunk cost thinking can be one reason traders move or ignore it.
This shows why risk management is not only about choosing the right level. It is also about deciding in advance how that level will be treated if the market reaches it.
On Capital.com, guaranteed stop-loss orders – where available – can close positions at the specified level even if the underlying market gaps, subject to product terms and any applicable fee. Standard stop-loss orders are not guaranteed and may be affected by slippage in fast-moving markets.
Deposit limits and daily loss caps can add broader controls by limiting how much can be lost during a difficult period. These tools do not remove trading risk, but they can support a more structured approach to decision-making.
Practical checklist
Before keeping a losing position open, consider asking:
- Has the original trade idea changed?
- Has the planned stop level been reached?
- Am I holding because of current analysis, or because I do not want to realise the loss?
- Would I enter the same position now?
- Does holding still fit my risk plan?
- Could this capital be used more effectively elsewhere?
These questions do not decide the trade on their own. They help bring the decision back to current evidence rather than past cost.
FAQ
What is the sunk cost trap in trading?
The sunk cost trap is the tendency to keep holding a losing position, or continue with a weak strategy, because of the money, time, or effort already invested. In trading, it can appear when a trader focuses on getting back to the entry price rather than reassessing the position based on current information. A sunk cost has already happened and cannot be recovered by the next decision alone. The more useful question is whether the position still has a clear forward-looking case.
What is the difference between the sunk cost trap and loss aversion?
Loss aversion is the tendency for losses to feel more painful than similar-sized gains feel rewarding. The sunk cost trap is one way this can show up in trading. For example, a trader may keep holding a losing position because closing it would make the loss feel final. In that case, the discomfort of realising the loss can influence the decision more than the current trade setup. Both ideas are linked, but they are not the same. Loss aversion explains part of the emotional pressure; the sunk cost trap describes the behaviour that can follow.
How do you avoid the sunk cost trap?
A practical way to manage the sunk cost trap is to use a forward-looking test: ‘Would I enter this position at the current price, based on what I know now?’ Pre-set stop-loss orders, position size limits, and trading journals can also help. They make decisions more structured and reduce the chance of reacting only to the discomfort of a loss. These tools can support better discipline, but they do not remove the risks of CFD trading. Standard stop-losses may not execute at the exact requested level in volatile conditions unless a guaranteed stop-loss applies.
