Sunk Cost and Avoiding the Sunk Cost Fallacy: A Guide to Smart Decision Making

Article Summary

We often find ourselves grappling with decisions that involve sunk costs. These costs are expenses that have already been incurred and cannot be recovered. Unfortunately, our tendency to factor in sunk costs when making decisions can lead to irrational choices, known as the sunk cost fallacy.

What is sunk cost?

Sunk costs are expenses or investments that have already been made and cannot be recovered. These costs have occurred in the past and are no longer relevant to future decision making. It’s important to understand that sunk costs are separate from future costs, which are expenses that will arise as a result of future actions or decisions.

Sunk costs can come in various forms, including financial expenditures, time, effort, and even emotional investment. They can arise from a wide range of situations, such as purchasing non-refundable tickets to events, completing costly projects, or investing in ventures that did not yield the expected returns.

The distinguishing characteristic of sunk costs is that they cannot be reversed or undone. Once the money has been spent, the time has been invested, or the effort has been exerted, those resources are irretrievable. Consequently, when evaluating future decisions, it is essential to recognize that sunk costs should not be factored into the decision-making process.

One common mistake people make is considering sunk costs as relevant when deciding whether to continue or discontinue an activity. This cognitive bias is known as the sunk cost fallacy, and it can lead individuals to make irrational decisions.

To illustrate, imagine you purchase a non-refundable ticket to a concert, but on the day of the event, you fall ill. Despite being unwell and unable to enjoy the concert, you might still feel compelled to attend because of the money spent on the ticket. In this case, the cost of the ticket is a sunk cost, as the money has already been spent and cannot be recovered. The rational decision would be to prioritize your health and forego the concert, but the sunk cost fallacy may tempt you to attend, leading to potential discomfort and further loss of time and energy.

What is the sunk cost fallacy?

The sunk cost fallacy is a cognitive bias that affects our decision-making process. It occurs when we factor in sunk costs, which are expenses that have already been incurred and cannot be recovered, when evaluating future decisions. Rather than making rational choices based on future costs and potential outcomes, we get trapped by the feeling that we must continue with a particular course of action because of what we have already invested.

The fallacy arises from our natural inclination to avoid losses and seek validation for past decisions. We tend to place undue importance on the resources we have already invested, whether it’s time, money, or effort, even when the costs are irretrievable and no longer relevant to the decision at hand.

For example, imagine you purchased a non-refundable ticket to a concert and, unfortunately, fell ill on the day of the event. Despite your illness, you might still feel compelled to attend the concert because of the money you spent on the ticket. In this scenario, the rational decision would be to prioritize your health and forego attending the concert. However, the sunk cost fallacy might persuade you to go against your best interest and attend the concert simply to justify the money spent.

The sunk cost fallacy can manifest in various aspects of life, including personal finances, relationships, careers, and business decisions. It often leads to suboptimal outcomes and prevents us from making decisions based on objective analysis and future potential.

To overcome the sunk cost fallacy, it is crucial to recognize that sunk costs are irrecoverable and should not influence future decisions. By reframing the decision-making process and focusing on the potential benefits and drawbacks, independent of past investments, we can make more rational choices.

Recognizing sunk costs

To make rational decisions, it’s crucial to recognize sunk costs and distinguish them from future costs. Here are some tips to help you identify sunk costs in various situations:

  1. Distinguish sunk costs from future costs: It’s essential to understand the difference between costs that have already been incurred and those that will arise in the future. Sunk costs are in the past and cannot be recovered, while future costs can be avoided. By recognizing sunk costs, you can shift your focus towards future benefits and potential outcomes.
  2. Evaluate emotional attachments: Emotions often play a significant role in decision making, especially when sunk costs are involved. Be aware of any emotional attachment you may have towards a sunk cost, such as the effort, time, or resources you have already invested. Strive to separate your emotions from rational thinking and evaluate the decision objectively based on future considerations.
  3. Consider opportunity costs: When evaluating the worth of a sunk cost, consider the potential benefits and opportunities that may arise by letting go of it. Ask yourself if holding onto the sunk cost prevents you from pursuing other valuable opportunities. Recognize that by continuing to invest in a sunk cost, you may be missing out on other fruitful ventures.

Overcoming the sunk cost fallacy

Escaping the grip of the sunk cost fallacy can be challenging, but it’s crucial for making sound decisions. Here are some strategies to help you overcome this cognitive bias:

  1. Reframe the decision: Instead of focusing on what you have already invested (the sunk cost), reframe the decision-making process by evaluating future costs and potential outcomes. Consider the benefits and drawbacks without letting sunk costs cloud your judgment. Ask yourself: If I were making this decision anew, what would I choose based on the expected future consequences?
  2. Seek outside perspective: Discussing the decision with someone who is not emotionally invested can provide valuable insights and help you detach from sunk costs. Seek advice from a trusted friend, mentor, or professional who can offer an objective viewpoint and help you consider the decision from a fresh perspective.
  3. Set clear decision criteria: Establish objective criteria for your decisions to avoid being swayed by sunk costs. Define specific goals and parameters against which you can evaluate the potential benefits and risks of the decision. By focusing on these criteria, you can make decisions based on logical reasoning rather than emotional attachment to sunk costs.
  4. Learn from experience: Reflect on past instances where the sunk cost fallacy influenced your decisions. Take the lessons learned from those experiences and use them to improve your decision-making process. By acknowledging the negative consequences of succumbing to the sunk cost fallacy, you can become more aware and resilient against its influence in the future.


What are some common examples of sunk costs?

Examples of sunk costs include non-refundable event tickets, completed home renovations, and investments in failed business ventures.

How does the sunk cost fallacy affect personal finances?

The sunk cost fallacy can lead individuals to hold onto underperforming investments or continue paying for subscriptions or memberships they no longer use, causing financial losses.

Can the sunk cost fallacy impact professional decision making?

Yes, the sunk cost fallacy can affect professional decision making. It may cause businesses to persist with failing projects or hold onto outdated technologies due to past investments.

Are there any situations where considering sunk costs is reasonable?

While considering sunk costs is generally irrational, there may be cases where the costs are substantial, and continuing with the investment might be justifiable after careful evaluation of potential future benefits.

Key takeaways

  • Sunk costs are expenses that have already been incurred and cannot be recovered.
  • The sunk cost fallacy occurs when we let past investments influence our future decision making.
  • Recognizing sunk costs is crucial for making rational choices.
  • Strategies for overcoming the sunk cost fallacy include reframing decisions, seeking outside perspective, setting clear criteria, and learning from past experiences.
View Article Sources
  1. Sunk costs – Economics Help
  2. Sunk cost – Britannica
  3. The Sunk Cost Effect In Pigeons And Humans – National Library of Medicine
  4. How Susceptible Are You to the Sunk Cost Fallacy? – Harvard Business Review
  5. Sunk Cost Fallacy – Economics Help