EMI Calculations and Checklists
How to calculate home loan EMI in India: formula, worked example and checklist
Calculate your home loan EMI by hand with the reducing-balance formula, see how interest and principal split over 20 years, and use a checklist before you borrow.
Your home loan EMI is calculated with the reducing-balance formula EMI = P × r × (1 + r)^n ÷ ((1 + r)^n − 1), where P is the loan amount, r is the annual rate divided by 12 and by 100, and n is the number of monthly instalments. For an illustrative ₹50 lakh loan at 8.5% for 20 years, the EMI is about ₹43,391, you repay about ₹1.04 crore in total, and about ₹54.1 lakh of that is interest. In the first year only about ₹99,500 of your ₹5.2 lakh of EMIs reduces the principal. Knowing this split explains why tenure, prepayment and rate changes matter so much.
All figures are illustrative. Use the EMI calculator for your own numbers.
Step by step: the EMI formula with real numbers
Take a ₹50,00,000 loan at 8.5% a year for 20 years.
- Monthly rate r = 8.5 ÷ 12 ÷ 100 = 0.0070833
- Number of instalments n = 20 × 12 = 240
- (1 + r)^n = 1.0070833^240 ≈ 5.4412
- EMI = 50,00,000 × 0.0070833 × 5.4412 ÷ (5.4412 − 1) ≈ 50,00,000 × 0.0070833 × 1.22516 ≈ ₹43,391
In a spreadsheet, the same result comes from PMT(8.5%/12, 240, -5000000).
Where each EMI goes
Interest each month is charged on the outstanding principal. The rest of the EMI repays principal.
- Month 1: interest = ₹50,00,000 × 0.0070833 = ₹35,417. Principal repaid = ₹43,391 − ₹35,417 = ₹7,974
- Year 1 total: interest about ₹4,21,182, principal about ₹99,511
- Year 10 total: interest about ₹3,07,420, principal about ₹2,13,274
Outstanding balance over time:
| End of year | Outstanding principal | Share of loan repaid |
|---|---|---|
| 5 | ₹44,06,359 | 12% |
| 10 | ₹34,99,691 | 30% |
| 15 | ₹21,14,937 | 58% |
| 20 | ₹0 | 100% |
After five years of EMIs, about 88% of the loan is still outstanding. This is normal for a long home loan and is why a part-prepayment early in the loan saves far more than the same amount late. See prepayment: reduce EMI or tenure.
Quick reference: EMI per ₹1 lakh
Multiply by your loan amount in lakh. For ₹45 lakh at 9% over 20 years: 45 × ₹900 = ₹40,500.
| Rate | 15 years | 20 years | 25 years | 30 years |
|---|---|---|---|---|
| 8.0% | ₹956 | ₹836 | ₹772 | ₹734 |
| 8.5% | ₹985 | ₹868 | ₹805 | ₹769 |
| 9.0% | ₹1,014 | ₹900 | ₹839 | ₹805 |
| 9.5% | ₹1,044 | ₹932 | ₹874 | ₹841 |
| 10.0% | ₹1,075 | ₹965 | ₹909 | ₹878 |
Going from 20 to 30 years lowers the EMI per lakh by only about 11% at 8.5%, but adds far more interest. The tenure comparison works through the numbers.
Why your lender's figure may differ slightly
- Rounding. Lenders round the EMI to the nearest rupee or ten rupees.
- Day count. Some lenders compute interest daily on the outstanding balance and on the actual days in the month; the EMI is the same but the split changes slightly month to month.
- Broken-period interest. If disbursement happens mid-month, you may pay interest for the days before the first full EMI cycle.
- Pre-EMI. For under-construction property, you may pay interest-only pre-EMI on disbursed amounts first; see pre-EMI vs full EMI.
- Rate resets. A floating rate changes over time, so the EMI or tenure will change; see what happens at a rate reset.
Checklist before you take the loan
- Affordability: your total EMIs, including this loan, fit within your budget with room for a rate rise of 1.5 percentage points. On the example loan, at 10% the EMI would be about ₹48,251.
- Eligibility: you know roughly how much lenders will offer on your income; see home loan eligibility on salary.
- Tenure: you have compared at least two tenures and chosen one deliberately.
- Co-applicant: you have considered whether a joint loan helps eligibility and tax; see joint home loans.
- Total cost: you have added fees and GST to the EMIs using the upfront charges calculator.
- Exit options: you know there is no prepayment charge on a floating-rate loan, and you know how a balance transfer would work if rates elsewhere fall.
- Paper trail: you have the sanction letter, Key Fact Statement and repayment schedule.
The home loan offer checklist lets you tick these off.
Common calculation mistakes
- Using the annual rate directly. The formula needs the monthly rate (annual ÷ 12).
- Using the property price instead of the loan amount. Only the borrowed amount is in P.
- Treating EMI × months as the cost. Add upfront charges and, for under-construction property, pre-EMI interest.
- Ignoring rate changes. A floating-rate EMI is an estimate for today's rate only.
- Comparing EMIs with different tenures. A lower EMI over 30 years is not a cheaper loan.
Frequently asked questions
Is the EMI the same every month?
At a constant rate, yes. When a floating rate resets, the lender changes the EMI, the tenure or both. Part-prepayments also change one or the other.
Does the lender charge interest on a monthly or daily basis?
Most lenders compute interest on a monthly or daily reducing balance. Your agreement says which. The difference in total cost is small; the reducing-balance principle is what matters.
How do I calculate total interest?
Multiply the EMI by the number of instalments and subtract the loan amount. For the example: ₹43,391 × 240 − ₹50,00,000 ≈ ₹54,13,879. This assumes the rate never changes.
Why does my statement show more interest than the calculator?
Check for broken-period interest at the start, pre-EMI interest, any rate rise since you borrowed, or charges debited to the loan account.
Sources
- Reserve Bank of India — Key Fact Statement and repayment schedule requirements
- RBI Kehta Hai — borrower awareness on loans
- National Housing Bank — housing finance information
