Girish (an illustrative profile) is 45 and runs a pharmacy in Nagpur. He keeps ₹10 lakh in a fixed deposit at 7% for his daughter's higher studies, twelve years away. He is in the 30% tax slab, and he feels the money is perfectly safe because the balance never falls.
In rupees, he is right. But will that ₹10 lakh still pay for the course it is meant to cover? This chapter shows how to answer that question with three numbers: the return, the tax and inflation.
In this chapter
- What inflation is, how India measures it and why your personal rate may differ
- The difference between nominal, post-tax and real returns
- A worked example comparing an FD with an equity fund over ten years
- How to inflate a goal's cost so you plan for the right number
What inflation is and how India measures it
Inflation is the general rise in prices over time. When inflation is 6%, something that costs ₹100 today costs about ₹106 next year. Your money has not shrunk, but each rupee buys a little less.
India's headline measure is the Consumer Price Index (CPI), a monthly price check on a fixed basket of goods and services such as food, fuel, housing, education and health, published by the Ministry of Statistics (MoSPI). CPI inflation was 5.54% in September 2026, up from 4.83% in August, under the new 2024-base series. Because inflation moves around year to year, many planners use a steady 6% a year for long-term goals, and that is the assumption used in this chapter.
Your personal inflation can be higher. A family paying school and college fees, or caring for elderly parents, spends more on categories that tend to rise faster than the average basket. Medical costs, for instance, are projected to rise 11.5% in 2026 (Aon), roughly double the headline figure.
| After | What ₹1 lakh buys, in today's money, at 6% inflation |
|---|---|
| 5 years | about ₹74,700 |
| 10 years | about ₹55,800 |
| 20 years | about ₹31,200 |
| 30 years | about ₹17,400 |
Nominal, post-tax and real returns
A return can be described in three ways, and only the last one matters for your goals:
- Nominal return: the headline rate, such as 7% on a deposit.
- Post-tax return: what is left after income tax on that return. A 7% FD taxed at 30% leaves 4.9%.
- Real return: the post-tax return after adjusting for inflation. It measures how much your buying power actually grows.
A quick approximation is real return ≈ post-tax return − inflation. The precise version is (1 + post-tax return) ÷ (1 + inflation) − 1, which gives a slightly smaller number. For everyday decisions the quick version is enough.
| Your tax slab | Post-tax return on a 7% FD | Approximate real return at 6% inflation |
|---|---|---|
| No tax payable | 7.0% | about +1.0% |
| 20% | 5.6% | about −0.4% |
| 30% | 4.9% | about −1.1% |
| 30% plus 4% cess | about 4.8% | about −1.2% |
Why tax timing matters as much as the rate
FD interest is added to your income and taxed at your slab rate every year, even if you never withdraw it. That annual tax shrinks the amount left to compound. Equity-oriented mutual funds (funds with at least 65% in Indian shares) work differently: you pay tax only when you sell. For FY 2026-27, gains on units held over 12 months are taxed at 12.5% on the portion above ₹1.25 lakh a year, and gains within 12 months at 20%. The full rules are covered in Capital Gains; here only the timing matters.
Worked example: Girish's ₹10 lakh over ten years
Assumptions: FD at 7%, tax at 31.2% (30% slab plus 4% cess, no surcharge), interest left to compound after tax. For comparison, an equity fund at an illustrative 10% a year, sold after ten years and taxed once at 12.5% plus cess on gains above ₹1.25 lakh. Inflation 6%.
- FD post-tax rate: 7% × (1 − 0.312) ≈ 4.82% a year.
- FD value after ten years: ₹10 lakh × 1.0482¹⁰ ≈ ₹16.0 lakh.
- Equity fund value before tax: ₹10 lakh × 1.10¹⁰ ≈ ₹25.9 lakh, a gain of about ₹15.9 lakh.
- Tax on the fund: (₹15.9 lakh − ₹1.25 lakh) × 12.5% × 1.04 ≈ ₹1.9 lakh, leaving about ₹24.0 lakh.
- Prices after ten years: 1.06¹⁰ ≈ 1.79, so divide each figure by 1.79 to get today's money.
- Result in today's money: the FD is worth about ₹8.9 lakh, less buying power than Girish started with. The fund, if it delivered 10%, would be worth about ₹13.4 lakh.
| FD at 7% | Equity fund at assumed 10% | |
|---|---|---|
| Value after 10 years, before tax | taxed yearly | about ₹25.9 lakh |
| Value after 10 years, after tax | about ₹16.0 lakh | about ₹24.0 lakh |
| In today's money (6% inflation) | about ₹8.9 lakh | about ₹13.4 lakh |
| Can the value fall in a bad year? | No (deposit) | Yes, sharply |
This does not make FDs bad. They protect the rupee amount, suit near-term needs and let you sleep at night. The lesson is narrower: a long-term goal funded only with taxable deposits is likely to fall short in real terms, and the gap widens with your tax slab.
Safe is not the same as risk-free: A deposit protects the number of rupees you hold. Inflation erodes what those rupees can buy. For goals ten or more years away, the bigger risk is often not a market fall but money that grows more slowly than prices.
Inflating your goal, not just your money
The other half of the calculation is the goal itself. Suppose the course Girish's daughter wants costs ₹15 lakh today. Even at 6% inflation it would cost about ₹30.2 lakh in twelve years, and more if education costs rise faster than CPI. Planning for ₹15 lakh would leave him well short, however safe the deposit.
The habit to build is simple: never compare a future goal with today's price. Turning each goal into a dated, inflation-adjusted target, and choosing the right rate for each, is the job of Turning a Wish Into a Goal.
Common mistakes to avoid
- Looking only at the headline rate. A higher rate taxed every year can leave you with less than a lower rate taxed only on sale.
- Using today's price for a future goal. At 6% inflation, costs double in about 12 years, so the target is usually far larger than it looks.
- Assuming CPI is your inflation. Families with heavy education or medical spending often face a higher personal rate.
- Chasing return to beat inflation in the short term. Equity can fall sharply; it suits goals at least five to seven years away, not next year's expenses.
Try this yourself: Write down your largest deposit or savings balance, its interest rate and your tax slab. Work out the post-tax rate, subtract 6%, and note whether the real return is positive. Then take one goal, write its cost today, and multiply by 1.79 if it is ten years away. Our financial health check can help you see the bigger picture.
Frequently asked questions
What is a good real return to aim for?
Any positive real return grows your buying power. For long-term goals, many plans assume a diversified portfolio might earn a few percentage points above inflation after tax over long periods, but this is an assumption and is not guaranteed. Near-term money should prioritise safety over real return.
Can a "safe" fixed deposit make me poorer?
In buying-power terms, yes. The rupee balance never falls, but if the post-tax interest rate is below inflation, each year the money buys a little less. That is not a reason to avoid deposits, only a reason not to rely on them alone for goals a decade or more away.
Why does my household feel inflation is higher than the official number?
The CPI is an average across a national basket. If a larger share of your spending goes to items rising faster, such as school fees, private healthcare or rent in a big city, your personal inflation will be higher than the headline figure.
Does a higher interest rate always mean a better real return?
No. What you keep depends on the rate, how and when it is taxed, and inflation over the same period. A slightly lower rate taxed only on sale can leave you with more buying power than a higher rate taxed every year, which is why comparisons should always be made after tax and after inflation.
To see how much of your own savings sits in low real-return accounts, try the financial health check.