Every choice uses a limited resource. Spending money on one goal leaves less for another, while using an evening for one activity means giving up a different use of that time. Opportunity cost helps reveal what a decision really requires you to sacrifice.
Opportunity cost is the value of the next-best alternative you give up when making a choice. It can involve money, time, income, flexibility, or personal satisfaction, but it does not equal the value of every option you rejected.
What Does Opportunity Cost Mean?
The Consumer Financial Protection Bureau defines opportunity cost as the cost of the next-best use of your money or time when you choose to buy or do one thing instead of another. The key phrase is next best. You compare your choice with the most valuable realistic alternative, not every imaginable possibility.
Suppose you can either work a Saturday shift or spend the day visiting friends. If you choose the visit, your opportunity cost may be the wages you could have earned. If you choose the shift, the opportunity cost may be the rest, enjoyment, or time with friends you gave up.
The answer can differ from person to person. Someone who urgently needs income may place more value on the work shift. Someone who has worked several weekends in a row may place more value on rest and relationships.
It Is Not the Total of Every Rejected Option
Imagine that you have one free evening and can exercise, study, or watch a movie. You choose to exercise.
You do not add the value of studying and watching the movie together. Your opportunity cost is whichever one would have been your next-best choice. If studying was more valuable to you than watching the movie, the value of the missed study time is the relevant opportunity cost.
A useful question is: What would I most likely have chosen if this option were unavailable? That answer usually identifies the next-best alternative.
Opportunity Cost Can Include Money and Time
Opportunity cost is not limited to a purchase price. A free activity can still have a cost because it uses time. A purchase can also reduce savings, emergency flexibility, or the ability to pay for another goal.
The Federal Reserve Bank of St. Louis explains that less visible costs can include time, productivity, personal well-being, professional development, and future earnings. Its examples also show why people should consider alternative uses of both money and time.
The following comparison shows how opportunity cost can appear in everyday decisions.
| Choice | Next-Best Alternative | Opportunity Cost to Consider |
|---|---|---|
| Take an unpaid day off | Work the scheduled shift | Wages and work benefits you would have received |
| Attend a free evening class | Exercise or rest | The value of the activity and time you gave up |
| Use $1,000 for a purchase | Keep it in emergency savings | Lost liquidity, financial flexibility, and possible interest |
| Complete a home project yourself | Hire someone and use the time elsewhere | Time, missed work, or another valuable activity |
Some opportunity costs can be measured in dollars, such as lost wages or interest. Others, including rest, family time, convenience, and enjoyment, require personal judgment.
Direct Cost and Opportunity Cost Are Related but Different
A direct cost is the money you pay for a choice. Opportunity cost is the value of the next-best use of the resources involved.
For example, attending a concert may require an $80 ticket and four hours. The ticket is a direct expense. The opportunity cost includes the best alternative use of that money and time, such as adding the money to savings and using the evening for another activity.
Consider both types of cost, but avoid counting the same sacrifice twice. The goal is not to create the largest possible cost estimate. It is to identify the resources used and the best realistic alternative you gave up.
Opportunity Cost Is Not the Same as Sunk Cost
A sunk cost is money, time, or effort that has already been spent and cannot be recovered. Opportunity cost concerns the alternative you give up because of a current or future decision.
Suppose you bought a nonrefundable movie ticket but dislike the movie after the first hour. The ticket price is now a sunk cost because leaving will not bring the money back. The relevant decision is whether the benefit of watching the remaining movie is greater than the value of the best alternative use of your remaining time.
The St. Louis Fed explains that unrecoverable past costs should not control a new decision. Future benefits, future costs, and the next-best available alternative are more relevant.
How to Use Opportunity Cost in a Decision
- List realistic choices. Exclude options that are not actually available.
- Identify the resources each choice uses. Consider money, time, income, energy, and flexibility.
- Find the next-best alternative. Do not combine every rejected option.
- Compare future benefits and costs. Leave unrecoverable sunk costs out of the new decision.
Opportunity cost does not automatically tell you which choice is correct. It makes the tradeoff visible. A reasonable choice is generally one whose expected benefit is more valuable to you than the next-best alternative you must give up.