Mental Accounting

The concept and violations of fungibility

In standard economics money is fungible: $100 from a paycheck and $100 from a lottery win have the same value and should be spent the same way. Richard Thaler (1980, 1985) pointed out that people actually divide money into mental accounts such as living expenses, savings and entertainment, and apply different rules to each. Keeping an emergency fund in a low-interest account while carrying high-interest credit card debt, for example, is hard to explain under fungibility. Heath and Soll (1996) showed experimentally that people set category budgets, for groceries or dining out, and cut spending in a category once its budget is exceeded. Hastings and Shapiro (2013) found that money freed up by falling gasoline prices was spent disproportionately on premium gasoline rather than other goods.

Hedonic editing and transaction utility

Using the value function of prospect theory (Kahneman and Tversky, 1979), Thaler explained how people combine or separate gains and losses. Under hedonic editing, gains feel better when segregated and losses when integrated. He also distinguished acquisition utility, the value of the good itself, from transaction utility, the pleasure or pain of the price compared with a reference price. People will pay more for the same beer bought at a fancy hotel than at a run-down store, showing how reference prices shape judgment. In Tversky and Kahneman's (1981) theater ticket experiment, people who lost cash were far more willing to buy a ticket than people who lost the ticket itself, a framing result interpretable as the lost ticket being charged to the theater account. Arkes and Blumer (1985) analyzed the sunk cost effect, continuing to invest because of money already spent, as a reluctance to close a mental account at a loss.

Risky choice, saving and applications

Thaler and Johnson (1990) reported the house money effect, in which prior winners treat gains as free money and take bigger risks, and a break-even effect in which losers gamble to recover. Shefrin and Statman (1985) explained the disposition effect, selling winning stocks too early and holding losers too long, through mental accounting and loss aversion, and Benartzi and Thaler (1995) interpreted the equity premium puzzle through myopic loss aversion from checking returns too often. Shefrin and Thaler's (1988) behavioral life-cycle hypothesis modified the life-cycle theory by assigning different propensities to consume from current income, assets and future income accounts. Prelec and Loewenstein (1998) analyzed how the timing gap between paying and consuming changes enjoyment. Thaler received the 2017 Nobel Prize in economics in part for this work, and mental accounting informs nudge-based savings policy design.

FAQ

What is mental accounting in simple terms?

It is the tendency to sort money into separate mental pots, such as salary, bonus or pocket money, depending on where it came from and what it is for, and to treat each pot differently.

What is the house money effect?

It is the tendency to treat money won from gambling or investing as not really one's own and therefore to risk it more readily.

Sources reviewed: 2026-10-26

References

1. Thaler, R. H. (1980). Toward a positive theory of consumer choice. Journal of Economic Behavior & Organization, 1(1), 39–60.
2. Thaler, R. H. (1985). Mental accounting and consumer choice. Marketing Science, 4(3), 199–214.
3. Thaler, R. H. (1999). Mental accounting matters. Journal of Behavioral Decision Making, 12(3), 183–206.
4. Kahneman, D., & Tversky, A. (1979). Prospect theory: An analysis of decision under risk. Econometrica, 47(2), 263–291.
5. Tversky, A., & Kahneman, D. (1981). The framing of decisions and the psychology of choice. Science, 211(4481), 453–458.
6. Shefrin, H. M., & Thaler, R. H. (1988). The behavioral life-cycle hypothesis. Economic Inquiry, 26(4), 609–643.
7. Thaler, R. H., & Johnson, E. J. (1990). Gambling with the house money and trying to break even: The effects of prior outcomes on risky choice. Management Science, 36(6), 643–660.
8. Arkes, H. R., & Blumer, C. (1985). The psychology of sunk cost. Organizational Behavior and Human Decision Processes, 35(1), 124–140.
9. Shefrin, H., & Statman, M. (1985). The disposition to sell winners too early and ride losers too long: Theory and evidence. Journal of Finance, 40(3), 777–790.
10. Prelec, D., & Loewenstein, G. (1998). The red and the black: Mental accounting of savings and debt. Marketing Science, 17(1), 4–28.
11. Heath, C., & Soll, J. B. (1996). Mental budgeting and consumer decisions. Journal of Consumer Research, 23(1), 40–52.
12. Hastings, J. S., & Shapiro, J. M. (2013). Fungibility and consumer choice: Evidence from commodity price shocks. Quarterly Journal of Economics, 128(4), 1449–1498.
13. Benartzi, S., & Thaler, R. H. (1995). Myopic loss aversion and the equity premium puzzle. Quarterly Journal of Economics, 110(1), 73–92.