Every bank and NBFC in India uses the same EMI formula, yet most borrowers do not know how their monthly payment is calculated. Understanding this helps you negotiate better terms and plan prepayments strategically.
The EMI formula
EMI = P × r × (1+r)^n / ((1+r)^n − 1)
Where: P = Principal loan amount, r = Monthly interest rate (annual rate ÷ 12 ÷ 100), n = Number of monthly instalments
Example: Home loan of ₹50 lakh at 8.5% for 20 years.
r = 8.5/(12×100) = 0.00708
n = 240 months
EMI = ₹50,00,000 × 0.00708 × (1.00708)^240 / ((1.00708)^240 − 1)
EMI ≈ ₹43,391/month
Why the reducing balance method matters
Indian banks use the "reducing balance" method — interest is charged only on the outstanding principal, not the original amount. This means your early EMIs are mostly interest, and later EMIs are mostly principal. In the above example, in month 1 you pay ₹29,167 in interest and only ₹14,224 towards principal.
How to reduce total interest paid
- Prepayment: Even one extra EMI per year reduces tenure significantly. On a ₹50L home loan, one extra payment per year saves approximately ₹4.8L in total interest.
- Shorter tenure: Moving from 20 to 15 years increases EMI by ~17% but reduces total interest by ~35%.
- Negotiate rate: Moving from 8.5% to 8.0% on ₹50L saves approximately ₹1.7L over 20 years.
Use our free EMI Calculator to try different scenarios with your loan details.
Fixed vs floating interest rate — how it changes your EMI
Most Indian home loans are floating-rate, tied to a bank's external benchmark (usually the RBI repo rate) plus a spread. When the RBI changes the repo rate, your bank typically adjusts your loan rate within a quarter, which changes either your EMI or your tenure, depending on what your bank's policy allows you to choose. Fixed-rate loans keep the same rate for a set period (or the full tenure), giving predictability but usually starting 1-2% higher than floating rates, since the bank is pricing in the risk of rates rising later.
The amortisation schedule — why your principal barely moves at first
An amortisation schedule breaks down every EMI into its interest and principal components across the loan tenure. On a 20-year loan, it typically takes 8-10 years before the principal component of your EMI exceeds the interest component — meaning for the first third to nearly half of a long-tenure loan, you're mostly paying interest, not reducing what you owe. This is precisely why prepaying early in a loan's life saves dramatically more interest than prepaying the same amount later: early prepayments strike directly at the high-interest, low-principal-reduction phase of the schedule.
Balance transfer — when it's actually worth it
Transferring your home loan to a new lender for a lower rate involves processing fees (typically 0.5-1% of outstanding principal) and paperwork. As a rule of thumb, a balance transfer is usually worth it if the rate difference is at least 0.5-0.75 percentage points and you have more than 5 years of tenure remaining — below that, the processing costs and effort often outweigh the interest savings. Always calculate the actual rupee savings on your specific outstanding principal and remaining tenure rather than going by the percentage difference alone.