Clearing debt before you invest: how borrowing really works
What an EMI is made of, how a floating rate resets, what prepaying changes, and how to weigh a certain loan cost against an uncertain return.
People often ask what to invest in long before they ask what their borrowing costs. The arithmetic usually runs the other way round: a loan is a fixed, certain cost, and clearing an expensive one is often the plainest use of spare money.
This page explains what sits inside an EMI, how a floating rate changes, what prepaying does, and how to think about whether a loan comes before investing. It recommends nothing, and every figure in it is an assumption used to show the working.
What an EMI is actually made of
An EMI, an equated monthly instalment, is one fixed amount you pay every month. “Equated” means the total stays the same, not that its contents do. Every instalment splits into two parts:
Interest for that month — worked out on the balance you still owe.
Repayment of the balance — whatever is left of the instalment once the interest has been taken.
Because the balance is largest at the start, the interest part is largest at the start too.
Why the early years are mostly interest
Take an assumed home loan of ₹50,00,000 at an assumed 8.5% a year for 20 years. The instalment is about ₹43,391 a month.
In the first month, interest is one month of 8.5% on ₹50,00,000 — about ₹35,417. That leaves roughly ₹7,974 going towards the balance. In month one, about 82 paise of every rupee you pay is interest.
The split moves slowly in your favour as the balance falls, and by the closing years almost the whole instalment is repayment. Across the full 20 years, at the assumed rate, you would pay about ₹1,04,13,879 — a little over ₹54 lakh of it interest.
This is not a trick. It is what charging interest on an outstanding balance looks like when the balance starts high. It is also why prepaying early changes much more than prepaying late.
What happens when a floating rate resets
A fixed-rate loan keeps the same rate throughout. A floating-rate loan is tied to an external benchmark — for most retail loans now, the policy repo rate — plus a spread the lender set when it sanctioned the loan.
When the benchmark moves, your rate moves with it at the next reset date. For benchmark-linked retail loans the Reserve Bank requires a reset at least once a quarter, and requires lenders to tell you clearly what changed.
What usually changes first is not your instalment. When the rate rises, most lenders keep the EMI where it is and lengthen the tenure instead. You feel nothing in your monthly outgo and pay for years longer. When the rate falls, the tenure shortens.
So read the reset letter rather than only watching your bank statement. You can normally ask for the EMI to be raised instead of the tenure extended, ask about a switch to a fixed rate, or prepay to pull the tenure back. The current framework is on the Reserve Bank’s own site at rbi.org.in.
Not all borrowing costs the same
“Debt” is one word for several different things. The rate, and the security behind the loan, decide how urgent it is.
A card balance you carry
A credit card charges nothing if you pay the full statement amount by the due date. The cost appears the moment you pay less and let the rest revolve.
Assume a card rate of 3.5% a month. That is about 42% a year before compounding, and over 51% once interest sits on earlier interest. On a revolving balance of ₹60,000 at that assumed rate, the first month’s interest alone is about ₹2,100.
A personal loan
A personal loan has no asset behind it, so the rate is higher than a secured loan but far below a card. Assume 14% a year on ₹5,00,000 over four years: the instalment is about ₹13,663 and you repay roughly ₹6,55,835 in all — about ₹1.56 lakh of interest.
A home loan
A home loan is secured against the property, runs for a long term, and carries the lowest rate of the three. Interest and repayment may also attract deductions under the income tax rules in force for the relevant financial year, lowering the real cost a little for some borrowers. The current position is on the Income Tax Department’s own site at incometax.gov.in.
A long tenure means the total interest is large even at a low rate, as the illustration above shows. That is a different problem from an expensive loan, with a different answer.
What prepaying does: tenure or EMI
A prepayment goes straight against your outstanding balance. Nothing else changes by itself, so the lender must adjust something — and you usually get to say which.
A worked illustration
Carry on with the assumed loan: ₹50,00,000 at an assumed 8.5% a year, 20 years, instalment about ₹43,391.
Three years in, then a prepayment
- After 36 months You have paid about ₹15.6 lakh of instalments, and the balance has fallen by only about ₹3.3 lakh, to roughly ₹46,74,300. The rest was interest.
- That month You put ₹5,00,000 into the loan, and the balance drops to about ₹41,74,300.
- From then on One of two things changes, and you usually get to choose which.
Avoids more
Keep the EMI, cut the tenure
The instalment stays ₹43,391.
The tenure falls from 204 months left to about 162 — about 42 instalments you never pay, roughly ₹18.2 lakh of payments avoided.
Frees up cash
Keep the tenure, cut the EMI
The tenure stays 204 months.
The instalment falls from ₹43,391 to about ₹38,750 — about ₹4,641 a month freed up, roughly ₹9.5 lakh of payments avoided.
Same ₹5,00,000, same assumed rate. The tenure route avoids roughly twice as much, because every month removed from the end of a loan is a month of interest you were going to pay.
Reduce the tenure or reduce the EMI?
Reducing the tenure is the cheaper of the two. It is also the less flexible: your monthly commitment stays as high as it was.
Reducing the EMI costs more in total but lowers the fixed call on your income. For someone with uneven income, or stretched to the edge of what they can service, that breathing room is the point.
Prepayment charges
A prepayment charge, sometimes called a foreclosure charge, is a fee for repaying ahead of schedule. Whether one applies depends on the loan.
For floating-rate term loans given to individual borrowers for purposes other than business, lenders are not permitted to levy foreclosure or prepayment penalties. Fixed-rate loans and business loans are a different matter: there a charge of a stated percentage of the amount prepaid, or of the balance, is common.
Three things to check before you prepay
- Your sanction letter and loan agreement, which state the charge, if any, and the notice required.
- Whether part-prepayment is treated differently from full closure. Some agreements allow a limited amount a year free.
- What you get afterwards — a revised schedule, and on full closure a no-dues certificate and your property papers back.
If a charge is levied where you believe it should not be, the lender’s grievance process comes first; the Reserve Bank’s site sets out the ombudsman route after that.
Comparing a loan rate with an investment return
The basic comparison is simple. If a loan costs you an assumed 9% a year, every rupee you put into it removes a 9% cost. A rupee put into an investment instead has to earn more than 9% after tax for you to come out ahead.
Why the comparison is not symmetrical
The two numbers are not the same kind of number, and this is the part most comparisons skip.
The loan rate is certain. The investment return is not.
Clearing a loan at an assumed 9% is certain to remove a 9% cost — the lender charges it whether markets rise or fall. An investment you assume might earn 11% a year may earn that, more, less, or nothing at all, and market-linked investments can fall in value. Nobody can promise you a figure.
Three more things tilt the comparison:
- Tax. The loan rate is the cost you bear, reduced by any deduction you are eligible for. An investment return is reduced by tax on gains when you sell. Compare after-tax with after-tax, for the financial year in question.
- Sequence. A loan does not wait. Interest accrues every month regardless of what your investments do that year.
- Behaviour. A large, expensive loan changes how you act in a market fall. People with heavy EMIs are the most likely to sell at the worst moment, because they have to.
None of that makes investing wrong while you hold a loan. It means the investment side needs a clear margin, not a tie, before it wins.
When it is reasonable to borrow and invest at the same time
Most households do both, for sound reasons.
- The loan is cheap and long. A home loan at a single-digit assumed rate over 15 or 20 years is a different creature from a card balance. Clearing it early is a choice, not a repair.
- The money is already committed. An emergency buffer you can reach quickly is not competing with the loan. It is what stops the next shock becoming another loan.
- Protection is in place. Term life and health cover matter more while a loan is outstanding, because the EMI does not stop if your income does.
- An employer match or statutory contribution is on the table. Money you would forfeit by not contributing is not money you chose to invest.
- A long-dated goal needs time. Education or retirement money has work to do that cannot be compressed into the years after a loan ends.
The useful question is not “loan or investing” but: is any of my borrowing expensive enough that nothing else should come first?
The one debt to clear first
If you are carrying a revolving credit card balance, or a cash advance on a card, that is the one to clear before anything else — before a home loan prepayment, and before fresh money goes into any investment.
The reason is only arithmetic. At an assumed 3.5% a month, the cost of that balance sits far above what a market-linked investment could reasonably be assumed to earn over the same period — and unlike the investment, the cost is certain.
There is no plausible version of the comparison where carrying a card balance wins. The same logic applies, less sharply, to other short, expensive borrowing: arrangements with charges folded into the price, loans against a card limit, and informal borrowing quoted monthly.