The Complete EMI Guide

By the EMI Cal Hub team · Updated October 2026 · 12 min read

1. EMI basics in one minute

An EMI (Equated Monthly Instalment) is the fixed payment you make every month to repay a loan. Each EMI has two parts: interest, charged on the balance you still owe, and principal, which reduces that balance. The EMI stays the same, but the split changes every month: early EMIs are mostly interest, later ones are mostly principal.

Here P is the loan amount, r is the monthly interest rate (yearly rate ÷ 12 ÷ 100) and n is the number of monthly instalments. You don't need to do this by hand: our EMI calculator does it instantly and shows the full schedule.

2. Flat rate vs reducing balance: the trap to avoid

Some lenders, especially for consumer goods and some car or personal loans, quote a flat rate. A flat rate charges interest on the original loan amount for the whole tenure, even though you're paying it down every month. A reducing balance rate charges interest only on what you still owe.

Here's the same loan, 1,00,000 for 3 years at "10%", calculated both ways:

The flat-rate loan costs almost twice as much interest, even though both say "10%". A 10% flat rate is roughly equivalent to an 18% reducing rate on a loan like this. Always ask which method is used, and compare offers on a reducing-balance basis.

3. How tenure changes your total cost

A longer tenure lowers your EMI, but you pay interest for more months. Here is a loan of 20,00,000 at 9% over different tenures:

Going from 10 to 25 years cuts the EMI by about a third, but nearly triples the interest. A sensible approach is to choose the shortest tenure whose EMI still fits comfortably, then prepay when you can.

4. Why 1% matters more than you think

On the same 20,00,000 loan over 20 years, moving from 9% to 10% raises the EMI from about 17,995 to about 19,300. That looks small per month, but over 240 months it adds roughly 3,13,000 in extra interest. When you're negotiating a rate or deciding whether to switch lenders, think in total interest, not just EMI.

5. How to calculate EMI in Excel or Google Sheets

Both Excel and Google Sheets have a built-in function for EMIs:

For example, =PMT(9%/12, 240, -2000000) returns about 17,995. The minus sign before the loan amount makes the result positive. To find how much of a given month's EMI is interest, use =IPMT(rate/12, month_number, months, -loan_amount); for the principal part, use =PPMT(...) with the same inputs. Or simply download a ready-made schedule as CSV from any of our loan calculators.

6. How much EMI can you afford?

Lenders usually cap the share of your monthly income that can go to all EMIs combined, often somewhere between 40% and 55% of net income. That's the maximum they'll allow, not a target. For your own comfort, consider:

• Keeping enough for rent or household bills, groceries, transport and school fees after EMIs.
• Saving something every month, even a small amount.
• Holding an emergency fund of several months of expenses, including EMIs.

Our loan eligibility calculator shows the lender's view; your budget decides the comfortable view.

7. Prepayment and part-payment strategies

• Prepay early. Because interest is front-loaded, extra payments in the first few years save the most.
• Choose "reduce tenure". After a part-payment, keeping the same EMI and shortening the loan usually saves more than lowering the EMI.
• Add a little every month. Small regular top-ups to your EMI can cut years off a long loan.
• Raise your EMI with your income. A modest increase each year has a similar effect.
• Check charges first. Some loans have prepayment or foreclosure fees; compare them with the interest saved.

Test your own plan with the loan prepayment calculator.

8. What happens if you miss an EMI

Missing a payment usually leads to a late-payment fee and, if the payment fails from your bank account, a bounce charge from both the lender and your bank. Interest may also be charged on the overdue amount. Most importantly, missed EMIs are typically reported to credit bureaus, which can lower your credit score and make future borrowing harder or more expensive.

If you expect to struggle with a payment, contact your lender before the due date. Many lenders can offer options such as a short payment holiday, restructuring or a change of due date.

9. Checklist for comparing loan offers

• Is the rate quoted on a reducing-balance basis?
• Is it fixed or floating? How often can a floating rate change?
• What is the processing fee, and is it deducted from the loan?
• Is insurance bundled into the loan amount?
• Are there prepayment or foreclosure charges?
• What are the late payment and bounce charges?
• What is the total cost (interest + fees) over the full tenure?

10. Loan glossary

Principal

The amount you borrow, or the part of it you still owe.

Tenure

The length of the loan, usually in months or years.

Rate of interest (ROI)

The yearly percentage charged on the outstanding balance.

Amortization

Paying off a loan through regular instalments that cover interest and principal.

Reducing balance

Interest charged only on the balance still outstanding each month.

Flat rate

Interest charged on the original loan amount for the full tenure.

Moratorium

A period when EMIs are paused, common in education loans. Interest often still accrues.

Foreclosure

Repaying the entire outstanding loan before the tenure ends.

Part-payment

An extra payment towards principal without closing the loan.

LTV (loan-to-value)

The loan amount as a percentage of the asset's value.

FOIR / DTI

The share of income going to debt repayments; lenders use it to set eligibility.

APR

Annual percentage rate; on some products it includes certain fees as well as interest.