The Break-Even Rule: When Prepaying Your Loan Actually Stops Making Sense
Published 29 June 2026 · Home Loans
Vijay in Delhi has 4 years left on his 20-year home loan. Outstanding principal: ₹12.3 lakh. He has ₹6 lakh sitting in a savings account earning 3.5%. The obvious move, he thinks, is to prepay the loan. His colleague disagrees — she says investing is better at this stage.
They are both right, depending on the numbers. And the numbers in late-stage loans are genuinely different from early-stage loans. The break-even analysis for Vijay surprises most people.
How the Interest-to-Principal Ratio Shifts Over 20 Years
Home loan interest is front-loaded. In year 1, roughly 81% of each EMI is interest. By year 10, the split is about 60% interest and 40% principal. In year 18, the ratio has flipped — approximately 30% interest and 70% principal.
| Loan Year | Interest % of EMI | Principal % of EMI | Approx. Outstanding |
|---|---|---|---|
| Year 1 | 81% | 19% | ₹49.2L |
| Year 5 | 74% | 26% | ₹45.6L |
| Year 10 | 60% | 40% | ₹37.9L |
| Year 15 | 42% | 58% | ₹24.1L |
| Year 18 | 30% | 70% | ₹12.3L |
What this means for prepayment: in year 1, every ₹1 lakh you prepay eliminates ₹1 lakh of principal that would have attracted 81% interest per EMI for 19 years. In year 18, that same ₹1 lakh eliminates principal that only has 2 years of interest ahead of it. The compounding benefit shrinks dramatically. That is why the "return" on prepayment drops as you approach the end.
Run this for your own numbers
Run the Break-Even Calculation →Vijay's Actual Break-Even Analysis
Outstanding principal: ₹12.3L. Remaining tenure: 4 years (48 months). Available ₹6L to either prepay or invest.
Option A — Prepay ₹6L: The ₹6L reduces outstanding to ₹6.3L. The loan closes in roughly 18 months instead of 48. Interest saved: approximately ₹2.3 lakh. That is a guaranteed return of 38% on the ₹6L over 4 years, risk-free.
Option B — Invest ₹6L for 4 years: At a 12% annual return (large-cap equity fund historical average), ₹6L becomes approximately ₹9.4L — a gain of ₹3.4L. Higher return, but with equity market risk over a 4-year window. A 4-year equity investment can easily return 5% or 20% depending on market conditions.
Verdict: investing narrowly wins in expected value — ₹3.4L vs ₹2.3L — but carries meaningful risk over a short horizon. For a conservative borrower, prepaying is still the right call. For someone with a high risk appetite and an existing emergency fund, investing makes sense.
When Prepaying Still Clearly Wins
If your loan rate is at or above what safe investments pay, prepaying is the dominant choice with no analysis needed. A home loan at 9% versus an FD at 7.5% — the 1.5% guaranteed difference, plus the loan's tax treatment, makes prepayment clearly superior.
If you are under psychological stress from the loan, prepaying is worth it even when the math slightly favours investing. The value of being debt-free — reduced anxiety, simplified finances, freed-up cash flow — is real and hard to quantify.
The key takeaway: prepaying is almost always the right call in years 1 through 12 of a 20-year loan. In years 13 through 20, the analysis becomes genuinely situation-dependent and worth doing carefully.
The Backwards Mistake Most Borrowers Make
Many borrowers do the opposite of what works: they invest aggressively in their early loan years (when prepayment would give the highest guaranteed return) and then start prepaying heavily in year 15 or 16 (when the return on prepayment is at its lowest). The compounding on early prepayments is where the real savings live. Year 3 prepayment pays off for 17 more years. Year 17 prepayment pays off for 3. The math is that simple.
Frequently Asked Questions
When does prepaying a home loan stop making financial sense?
When the effective interest saving from prepayment is lower than the expected return from investing the same amount. In the last 5 years of a loan, with only ₹10–15L outstanding, the interest saved on ₹5L prepayment may be less than what ₹5L earns in equity funds over 5 years.
What percentage of EMI is interest in the early vs late years?
On a ₹50L@8.5%/20yr loan: in year 1, about 81% of each EMI is interest. By year 15, about 42% is interest. In year 18, about 30% is interest and 70% is principal repayment.
Is it better to prepay a loan or invest at the end of the loan tenure?
Likely better to invest. If you have 3 years remaining on a ₹10L outstanding loan at 8.5%, the interest savings from prepayment are modest. Investing ₹5L in equity funds for 3 years at 12% may yield more — though returns are not guaranteed.
What is the break-even point for home loan prepayment vs investment?
Compare: (A) interest saved if you prepay ₹X today, vs (B) expected return if you invest ₹X for the remaining tenure. If B > A, investing wins. If A > B, prepaying wins. This varies by outstanding principal, remaining tenure, and expected investment return.
Should I keep paying EMI or invest after the first 10 years?
After 10 years of a 20-year loan, you have paid most of your interest (amortization is front-loaded). At this point, maintaining the EMI and separately investing any surplus often makes more sense than making large prepayments.
How many years are left on your loan — and have you calculated whether prepaying now saves more than what the same money would earn invested for that period?