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Prepay the Loan or Invest?

Compare putting spare money against your loan with investing the same money in a SIP — judged over the same number of years, with the EMI you free up counted in.

Your loan

₹
% p.a.
years

The money you are deciding about

₹

Over and above the EMI

₹

A bonus or maturing deposit

% p.a.

An assumption, not a promise

Your EMI is ₹26,035. Both strategies below spend ₹41,035 every month for 20 years. Same money, same finish line.

Prepay the loan

The surplus goes against the loan until it clears, then the whole ₹41,035 is invested for the years that remain.

Loan clears in
8 years 8 months
Interest paid
₹12,41,128
Invested after that
₹56,07,200

Worth at the end of 20 years

₹1.20 Cr

Invest the surplus

Ahead

The loan runs its full term on the normal EMI, and the surplus goes into a SIP from month one.

Loan clears in
20 years
Interest paid
₹32,48,327
Total invested
₹36,00,000

Worth at the end of 20 years

₹1.50 Cr

Investing is ahead by ₹29.89 L after 20 years.

At an assumed 12% against a loan rate of 8.5%, the surplus works harder invested. That gap only exists if the 12% actually materialises and you stay invested through the falls — drop the assumption to 8.5% and the two are identical. Prepaying still buys certainty and a debt-free household 11 years 4 months sooner.

All figures are pre-tax. This does not model Section 24(b) interest relief, 80C principal relief, or capital-gains tax on redemption — each can move the answer. It is a comparison, not financial advice.

Complete Guide

About the Prepay Loan vs Invest Calculator

You have spare money and a loan running: pay it down, or invest it? Prepaying earns a guaranteed, tax-free saving equal to your interest rate. Investing may beat that, but only if post-tax returns actually exceed the rate — and only if you hold through the volatility on the way. This free calculator runs both strategies side by side over the same years, spending identical money every month in both, so the finish-line comparison is fair. Home-loan holders agonising over bonuses and personal-loan borrowers counting every rupee get the same honest arithmetic, entirely in-browser.

The one comparison that matters

Strip away opinions and one equation remains: prepaying a loan at R% is financially indistinguishable from earning a guaranteed, tax-free R% on that money, because every rupee prepaid permanently cancels interest you would otherwise have paid. Investing therefore wins only if the expected post-tax return clears your loan rate — and clears it by enough to justify accepting risk. Against a 9% home loan, a bank FD paying 7% loses clearly, especially after tax: in the 20% slab that FD nets about 5.6%. An equity fund assumed at 12% offers a two-point cushion, which is meaningful over fifteen-plus years but arrives attached to drawdowns that regularly reach 20–30%. At exactly your loan rate the two paths tie on paper — and since one side of the tie is certain while the other is hoped-for, many households reasonably treat a tie as a vote for prepaying.

Why many comparisons mislead — and how this one stays fair

The usual mistake compares interest saved against the SIP corpus while forgetting the freed-up EMI. When aggressive prepayments close your loan years early, the entire EMI becomes investable surplus for every remaining year — ignore it and the comparison quietly rigs itself in favour of staying invested. Here, both strategies spend an identical monthly budget — your EMI plus your surplus — for the whole original tenure. In the prepay path the loan closes early and the freed budget is invested for the years left; in the invest path the loan runs full term while the surplus enters the SIP from month one. Both end at the same finish line, so net worth is compared like for like. Honesty about limits matters too: all figures are pre-tax, and Section 24(b) interest relief, 80C principal benefits and capital-gains tax on redemption are deliberately not modelled — each can shift the answer in your situation.

Before you decide

Sequence matters more than optimisation. Build an emergency fund first — six months of expenses somewhere reachable — because money pushed into a loan is very hard to pull back out, while a mutual fund redeems in days. Next, know your rate: personal loans and credit-card EMIs at 14–24% make prepaying close to automatic; home loans near 8.5–9.5% create the genuine dilemma worth calculating carefully. Tax positions tilt things further — claim home-loan deductions under the old regime and your effective prepay return drops below the headline rate. Many households ultimately split the surplus between both goals, capturing some certainty and some upside at once. And whatever you choose, re-run the numbers whenever your rate, tenure or surplus changes, because the break-even moves with them. This tool provides education, not financial advice.

Worked Example

Real numbers, start to finish

The decision compresses neatly into rates. Say your outstanding home loan charges 9% and you have ₹10,000 of spare monthly income. Three destinations compete for that money, each with a different character of return:

DestinationReturn usedGuaranteed?Illustrative verdict
Prepay the loan9% — the loan rate itselfYes — it is interest never paidBaseline: certain and tax-free
Bank FD7% pre-tax; ≈ 5.6% post-tax at the 20% slabYes (rate fixed for the term)Loses to prepaying by ≈ 3.4 points
Equity fund SIP12% expected — not promisedNoMay win over long horizons; volatile path

Same spare money, three destinations (illustrative rates)

Against the FD, prepaying wins outright — 9% certain beats 5.6% certain, no debate. Against equity, the two-point edge exists only if the 12% materialises and you stay invested through every fall; shorten the horizon or shade the assumption downward and the edge evaporates. That asymmetry — certain versus conditional — is the entire decision. Rates shown are illustrative; your loan rate and tax slab set your own numbers.

Video slot: prepay-vs-invest-walkthrough.mp4

Entering a running home loan with ₹15,000 spare monthly, moving the expected-return field from 8.5% to 13% to show the verdict flip at the break-even, and pointing out the freed-EMI line inside the prepay card.

Coming soon
Simple Step-by-Step Guide

How to Use Prepay Loan vs Invest Calculator Online

Follow these simple steps to use Prepay Loan vs Invest Calculator securely in your web browser.

  1. 1

    Enter Loan Details

    Type remaining principal loan amount, interest rate (%), and tenure.

    01-prepay-vs-invest-enter-loan-details.png

    Replace with a real capture

  2. 2

    Enter Investment Surplus

    Type or enter available monthly surplus cash and choose expected mutual fund return rate.

    02-prepay-vs-invest-enter-investment-surplus.png

    Replace with a real capture

  3. 3

    Click to Calculate Net Worth

    Click compare to calculate guaranteed interest saved versus compounded investment returns.

    03-prepay-vs-invest-click-to-calculate-net-worth.png

    Replace with a real capture

Technical Specs

Features & Specifications

Comparison Scope

Guaranteed Loan Interest Saved vs Compounded Equity SIP

Horizon

Remaining Loan Tenure

Privacy Status

100% In-Browser Local Processing

100% Free & Private In-Browser Processing

Rupix operates on a zero-upload architecture. All computations, file parsing, and transformations occur locally inside your web browser. No document bytes, sensitive text, or personal data are ever uploaded or transmitted to remote servers.

Highlights

Why use Rupix Prepay Loan vs Invest Calculator?

Dual Strategy Comparison

Side-by-side simulation of loan interest savings versus compounded market returns.

Freed EMI Effect

Models reinvesting former EMI payments into investments once the loan is paid early.

Net Wealth Projection

Clear summary of which strategy yields higher final net worth.

Q&A

Frequently Asked Questions

Compare your loan rate with the post-tax return you realistically expect from investing. Prepaying guarantees a saving equal to the loan rate; investing must beat that after tax, with volatility accepted. At an 8.5% loan versus 12% expected equity, investing wins on paper provided you hold through falls; against a 14% personal loan, prepaying almost always wins.
Because ignoring it rigs the comparison. Once aggressive prepayments close the loan, the whole EMI frees up for the remaining years. Reinvesting it means both strategies spend identical money over identical periods, making the ending figures genuinely comparable.
Exactly your loan interest rate. Below it, prepaying wins; above it, investing pulls ahead. That break-even is why the real question is the post-tax return you can achieve — not the size of the loan.
Under the old regime, Section 24(b) shields up to ₹2 lakh of self-occupied home-loan interest and 80C covers principal, effectively lowering your true loan cost — which weakens prepaying's case. The new regime drops most such deductions. This calculator shows pre-tax figures, so adjust for your own slab.
Floating-rate home loans to individuals cannot be penalised under RBI rules. Fixed-rate home loans, personal loans and business loans often can be — commonly 2–5% of the prepaid amount. A penalty that size belongs inside the calculation, not outside it.
Yes, always. Money inside a loan is difficult to retrieve — most lenders will not hand it back without a fresh application — while mutual funds redeem within days. Park six months of expenses somewhere accessible first, whatever the maths suggests.
No. Figures are pre-tax and in nominal rupees — but identically so for both strategies, so the comparison between them stays valid even though neither number predicts future purchasing power.
Entirely. Loan balances and investment plans are computed in your browser alone — nothing uploads, stores or logs, no account is needed, and no adviser follows up afterwards.