How Inflation Affects Your Savings

A practical method

Inflation reduces the purchasing power of money over time. A savings balance can rise in nominal terms while buying less if its after-fee, after-tax return is below inflation. Planning is clearer when nominal balances and inflation-adjusted, or real, values are shown separately.

1. Project the nominal balance: Apply deposits and the assumed account or investment return.
2. Choose an inflation scenario: Use a transparent annual assumption and test more than one rate for long horizons.
3. Convert to today's purchasing power: Divide the future nominal value by (1 + inflation rate)^years.
4. Compare the real return: A close approximation is nominal return minus inflation, but the exact relation is (1+nominal)/(1+inflation)−1.

Worked example

If $10,000 becomes $12,000 in five years while inflation averages 3%, its value in today's money is about $12,000 ÷ 1.03^5 = $10,352. The nominal gain is $2,000, but the estimated real purchasing-power gain is much smaller.

Checks, edge cases, and common mistakes

• Inflation is not constant and can differ across spending categories, households, and countries.
• Use after-fee and after-tax returns when those costs apply to the account.
• Do not compare a future nominal goal directly with today's price.
• Test conservative and adverse scenarios instead of relying on one forecast.