How an EMI divides between interest and principal
Learn / Money essentials
Compare repayment cost, repayment time and cash-flow pressure before judging a loan by its EMI.
SiP Money editorial · 5 minute read · Educational guide
The useful distinction
At 12% nominal annual interest on ₹1,00,000, 12 monthly end-of-month payments are about ₹8,885; 24 are about ₹4,707. The lower payment extends the debt and increases modelled interest from roughly ₹6,619 to ₹12,976, before fees.
In this guide
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What happens inside an instalment
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A smaller EMI can mean more interest
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Read beyond the advertised rate
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Test the commitment against your income
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Compare two repayment paths
An EMI can fit your monthly budget while the full loan still costs more than you expect. To understand the commitment, look at the amount borrowed, the interest calculation, the repayment period and the fees together. The monthly instalment is only one part of the picture.
RBI's Key Facts Statement guidance describes an EMI as a monthly repayment containing principal and interest that amortises the loan over the repayment period. Amortisation simply means paying down the outstanding loan through a schedule of repayments. [1]
What happens inside an instalment
On a standard reducing-balance loan, interest for a period is calculated on the outstanding principal using the loan's agreed convention. The remainder of the payment reduces principal. As that balance falls, the interest component generally falls too, provided the rate and instalment remain unchanged.
Consider a purely illustrative ₹5,00,000 loan over 36 months at a nominal annual rate of 12%, calculated as 1% per month. Assume monthly payments at the end of the month, no fees, no missed payments and no rate changes.
The EMI is approximately ₹16,607. In month one, interest is ₹5,000 and about ₹11,607 repays principal. The remaining balance is approximately ₹4,88,393. Month two's interest is therefore about ₹4,884, leaving roughly ₹11,723 of the same EMI to reduce principal.
The example uses unrounded calculations internally. An actual lender may use different day-count conventions, disbursal dates and rounding, so compare the illustration with the lender's own repayment schedule.
A smaller EMI can mean more interest
For the same hypothetical principal and rate, extending the term to 60 months reduces the EMI to approximately ₹11,122. But total interest rises from about ₹97,858 over 36 months to about ₹1,67,333 over 60 months, before any charges.
The longer term eases the monthly cash requirement by about ₹5,485 in this example while adding about ₹69,476 of interest. Whether that trade-off is workable depends on your circumstances, but the arithmetic should be visible before you commit.
Read beyond the advertised rate
Ask for the Key Facts Statement where applicable, the repayment schedule, the total amount repayable and a clear list of fees. RBI's KFS framework uses the annual percentage rate, or APR, to express credit cost including interest and associated charges. Its repayment schedule helps you see the outstanding balance over time. [1]
Compare like with like. A flat-rate quote and a reducing-balance quote are not directly comparable just because both display an annual percentage. Check how much money you actually receive after deductions, when payments begin and whether optional products have been added.
Test the commitment against your income
For a floating-rate loan, ask how a rate change can affect the EMI, tenure or both, and what your contract says about any available choices. For prepayment, confirm the current applicable rules and loan terms rather than assuming that every borrower faces the same charge.
Place the instalment in your essential-expenses budget. Then test a temporary fall in income. A useful borrowing decision considers the payment you can manage today, the cost over the full term and the room left for the rest of your life.
Sources and further reading
Source check: 11 October 2026. Refer to the period and terms applicable to your decision.
Compare two repayment paths
Keep principal and rate the same, then compare two tenures. Write down the EMI, total interest and amount still owed after the first year. Separately list fees, insurance and prepayment terms from the lender’s documents.
Try this before your next decision
Write your assumptions beside the numbers. Change one assumption at a time and compare the effect. If the answer depends on a rule, a contract or your own circumstances, check that evidence before acting.
Put the question into numbers →
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About this guide
Prepared for SiP Money’s educational publication. Source dates above refer to the original factual check; native reading edition and worked exercise updated 18 October 2026. No named professional review is claimed. Examples are hypothetical, exclude unstated taxes and costs and do not assess personal suitability.
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