Fundamentals

Money illusion: why more money does not always mean more purchasing power

By Daniel Sardá · Published on July 11, 2026

3 min read530 words

Money illusion occurs when people focus on nominal amounts without adjusting for changes in prices and purchasing power.

Money illusion is the tendency to focus on the nominal amount of wages, prices, savings, or returns without fully adjusting for changes in the price level. A larger number of currency units does not necessarily buy more goods and services.

The key distinction is between nominal and real values.

Nominal value and real value

Nominal value is the amount printed on a paycheck, price tag, account statement, or contract. Real value reflects what that amount can purchase after changes in prices.

| Measure | What it shows | Question to ask | |---|---|---| | Nominal wage | Currency units earned | How much money did I receive? | | Real wage | Purchasing power of those earnings | What can the wage buy? | | Nominal return | Percentage credited to savings | How much did the balance rise? | | Real return | Return after inflation | Did purchasing power rise? |

A wage example

Suppose a monthly wage rises from 1,000 to 1,080 units, an 8 percent nominal increase. If the relevant prices rise by 12 percent, the worker receives more units but can buy less than before. The nominal wage increased while the real wage fell.

The reverse is also possible. If wages rise by 8 percent and prices by 3 percent, purchasing power improves. A nominal increase is not automatically an illusion; it must be compared with prices.

Prices and monetary memory

People often remember an old price and treat it as a stable benchmark. Yet currencies and price levels change. A product that costs twice as many units is not necessarily twice as expensive in real terms if incomes and other prices have also changed substantially.

Good comparison uses a consistent period and an appropriate price measure rather than isolated numbers.

Savings and interest

A savings account may pay 6 percent interest. If inflation is 8 percent, the balance grows in nominal terms while its purchasing power declines. As a rough approximation:

real return ≈ nominal return − inflation

For precise calculations, compounding and taxes also matter.

Debt and inflation

Fixed nominal debts can become easier to repay when incomes and prices rise, though the effect depends on interest rates, contracts, and the borrower’s income. Lenders may anticipate inflation and charge higher rates, so inflation is not a universal benefit to debtors.

Why money illusion occurs

Nominal numbers are visible and easy to compare. Real values require a price index, a time period, and judgments about which prices matter. Contracts and accounting systems are also usually written in nominal units.

This does not mean people are simply irrational. Information is costly, inflation varies, and no general index perfectly represents every household.

How to avoid it

Compare percentage changes over the same period, examine inflation-adjusted wages and returns, and consider the prices that dominate your own budget. For long-term comparisons, use a consistent inflation index and state its limitations.

A useful synthesis

Money illusion is a warning against reading currency amounts in isolation. The number matters, but purchasing power determines the economic result. The right question is not only “How much more money is there?” but “What can it buy now?”