🏦 LOANS · DIRECT ANSWER
Should You Prepay Your Home Loan or Invest? The Break-Even Is 8.89%
THE DIRECT ANSWER
On a ₹40 lakh home loan at 9% over 20 years, an extra ₹10,000 a month closes the loan in 11 years 10 months instead of 20. But putting that same ₹10,000 into an investment returning 12% leaves you with ₹99,91,479 after 20 years, against ₹76,71,126 if you prepay first and invest later: a gap of ₹23,20,354. The break-even is a return of about 8.89%. Above it, investing wins. Below it, prepaying wins.
Which actually leaves you with more money?
Take a ₹40,00,000 loan at 9% for 20 years. The EMI is ₹35,989. You have a spare ₹10,000 a month and 20 years to run. Two options, measured at the same finish line: month 240.
| A · Prepay first | B · Invest alongside | |
|---|---|---|
| Monthly outgo | ₹45,989 to the loan | ₹35,989 EMI + ₹10,000 invested |
| Loan closes | 11 years 10 months | 20 years |
| Total interest paid | ≈ ₹10.8 lakh | ₹46,37,369 |
| Then | Invest ₹45,989/mo for the remaining 98 months | N/A |
| Wealth at month 240 | ₹76,71,126 | ₹99,91,479 |
Option B ends ₹23,20,354 ahead: despite paying ₹35 lakh more in interest. Compounding on money invested early outruns interest saved on debt.
What is the break-even return?
Solving for the return at which both options finish level gives approximately 8.89%: slightly below the 9% loan rate, because prepayment frees up cash flow that then gets invested.
💡 THE KEY INSIGHT
Prepaying a 9% loan is effectively a guaranteed, tax-free 9% return. Investing is an expected 12% with real risk. The question is not which number is bigger. It is whether the extra ~3% is adequate compensation for the uncertainty: and for your specific situation.
Then why does everyone say prepay?
Because the arithmetic above assumes three things that often are not true:
- You actually invest the money, every month, for 20 years. Money not sent to the loan has a way of being spent. A prepayment is enforced; a SIP is a decision you must keep re-making.
- You earn 12% and stay invested through every fall. Selling during a crash turns the expected return into a realised loss.
- The horizon is genuinely 20 years. Over 5 to 7 years, equity returns are far less dependable, and the guaranteed 9% starts looking better on a risk-adjusted basis.
Prepaying is the lower-return, higher-certainty option, and it works even if you are not disciplined. That is why it is the common advice: not because the maths favours it.
When should you prepay anyway?
Return is not the only thing that matters. Prepay when:
- The loan would run past retirement. An EMI in retirement is drawn from a finite corpus, not from salary. We covered this at length in Rajesh's case: at 54 with 18 years left, the loan would have run to age 72. There, prepaying was right for cash-flow reasons, not return reasons.
- Your income is variable or insecure. A smaller EMI is a smaller monthly obligation to meet in a bad year.
- The debt genuinely bothers you. Sleeping well has a value that does not appear in a spreadsheet, and it is not irrational to buy it.
- You have no emergency fund or term cover yet. Then neither option applies: fix that first.
🟡 AGE CHANGES THE ANSWER
At 30 with a 20-year horizon, the maths favours investing. At 54 with a loan running past 65, it favours prepaying: the horizon is too short for equity to be dependable, and the retirement cash-flow risk is real. The same question has different right answers at different ages.
Can you do both?
Yes, and for most people that is the sensible answer. Splitting ₹10,000 into ₹5,000 extra EMI and ₹5,000 invested captures part of both: the loan shortens, a corpus builds, and you are not betting the entire decision on one assumption about returns.
A reasonable sequence before either: an emergency fund of six months' expenses, adequate term cover, and health insurance. Prepay-versus-invest is a question for money left over after those.
Assumptions
₹40,00,000 at 9% p.a. reducing balance, 20-year term, EMI ₹35,989. Extra ₹10,000 applied monthly from month one. Investment assumed at 12% p.a. compounded monthly, beginning-of-month instalments, returns constant: real returns vary year to year. No prepayment penalty assumed (RBI guidance prohibits it on floating-rate loans to individuals; verify for your loan type). Ignores tax deductions on home loan interest and principal, which would narrow the gap, and capital gains tax on the investment, which would narrow it further. Both options compared at month 240.
The one-line summary
Above about 8.89% expected return, investing wins on paper. Below it, prepaying wins. But if you are near retirement, if your income is unstable, or if you will not actually invest the money every month, prepay: the certain 9% beats an expected 12% you never capture.
Frequently asked questions
Mathematically, investing wins if your return exceeds about 8.89% on a 9% loan. On a ₹40 lakh loan at 9% with ₹10,000 extra monthly, investing at 12% leaves about ₹99,91,479 after 20 years versus about ₹76,71,126 if you prepay first and invest afterwards. Prepaying is guaranteed; investing carries market risk and requires sustained discipline.
On a ₹40 lakh loan at 9% over 20 years, paying ₹10,000 extra each month closes the loan in about 11 years 10 months instead of 20, cutting total interest from ₹46,37,369 to roughly ₹10.8 lakh: a saving of about ₹35 lakh.
For floating-rate home loans taken by individuals, RBI guidance prohibits foreclosure and prepayment charges. Fixed-rate loans may still attract a charge. Confirm the terms in your own loan agreement before making a large prepayment.
Reducing tenure saves far more interest, because interest accrues on the outstanding balance over time. Reducing the EMI improves monthly cash flow but keeps you in debt longer. Choose tenure reduction unless you specifically need the monthly relief.
Run your numbers: Prepayment calculator · SIP calculator
All figures are illustrative and calculated at the stated assumptions, not a projection of returns. Mutual fund investments are subject to market risks; read all scheme-related documents carefully. Educational content only, not personalised advice. Consult a SEBI-registered investment adviser before deciding.