What is Amortisation? Meaning, Definition & How It Works
Amortisation is essentially the math behind every EMI you pay. When you borrow ₹10,00,000 for a car or a home, the lender does not ask for the lump sum back at once.
Instead, they spread it across a fixed number of equal installments, structured so each one covers some interest on the outstanding amount and repays some of the principal.
In Hindi, amortisation is usually translated as “rin parishodhan” (ऋण परिशोधन), which literally means loan repayment or loan redemption, though most Indian bank statements and loan documents simply use the English term.
Amortisation of a loan specifically refers to this gradual paydown process for borrowed money, as distinct from the accounting use of the same word, which describes writing off the cost of an intangible asset, such as a patent or trademark, over several years.
RBI guidelines require lenders to share a clear repayment schedule with borrowers, including how the interest-principal split changes over the tenure, which matters most for floating-rate home loans where the rate, and therefore the schedule, can change.
Did you know? A home loan amortised over 20 years can end up costing more in total interest than the original amount borrowed, simply because of how front-loaded the interest portion is in the early years.
How does amortisation work?
Amortisation runs on a simple loop that repeats every month until the loan is cleared.
- The lender calculates a fixed EMI. Using the loan amount, interest rate, and tenure, the EMI is set so the loan is fully repaid, principal plus interest, by the end of the term.
- Interest is calculated on the outstanding balance. For the first installment, this means the full principal; for later installments, it means whatever is left.
- The interest portion is deducted from the EMI. Whatever remains of the fixed EMI goes toward reducing the principal.
- The outstanding balance drops. A slightly lower balance means slightly less interest is due next time.
- The cycle repeats with a shifting mix. Each month, the interest share of the EMI shrinks a little and the principal share grows a little, even though the EMI itself never changes, until the final installment brings the balance to zero.
This month-by-month breakdown is what lenders call an amortisation schedule, or sometimes an amortisation plan.
Pro tip: If you make a lump-sum prepayment early in the loan, ask your lender to reduce the tenure rather than the EMI. Since early EMIs are mostly interest, shortening the tenure saves you far more money over the life of the loan.
Amortisation formula and calculation
Amortisation Formula (EMI):
EMI = [P × R × (1 + R)^N] ÷ [(1 + R)^N − 1]
Where:
- P = Principal, the loan amount you borrow
- R = monthly interest rate (the annual rate divided by 12, expressed as a decimal)
- N = number of monthly installments, or the loan tenure in months
This formula produces a constant EMI that, paid every month, exactly clears both principal and interest by the final installment.
You rarely need to compute it by hand, since most bank, NBFC, and housing finance company websites have an EMI or amortisation plan calculator that does this instantly once you enter the loan amount, rate, and tenure.
Amortisation example: home loan EMI breakdown
Priya, a 35-year-old working in Bengaluru, takes a ₹30,00,000 home loan at 8.5% per annum for 20 years (240 months).
Given:
- Principal: ₹30,00,000
- Interest rate: 8.5% per annum (monthly rate ≈ 0.708%)
- Tenure: 240 months
Calculation: Applying the EMI formula above gives Priya a fixed monthly payment of ₹26,035.
| Month | EMI | Interest portion | Principal portion | Outstanding balance |
|---|---|---|---|---|
| 1 | ₹26,035 | ₹21,250 | ₹4,785 | ₹29,95,215 |
| 120 (Year 10) | ₹26,035 | ₹14,952 | ₹11,083 | ₹20,99,815 |
| 240 (final) | ₹26,035 | ₹183 | ₹25,852 | ₹0 |
This means that in Priya’s very first EMI, more than 80% goes toward interest. Her principal portion does not actually overtake her interest portion until around month 143, roughly twelve years into a twenty-year loan.
Amortisation methods
Most retail loans in India use one method, but a few alternatives exist for specific products and accounting situations.
Equal installment method
Also called the EMI or annuity method. The total payment stays fixed every month, while the mix between interest and principal shifts gradually over the tenure. This is the standard method for home loans, car loans, and personal loans in India.
Straight-line method
The principal portion repaid stays constant each period, so the total payment actually falls over time as the interest portion shrinks on a steadily reducing balance.
This method is more common in accounting, for amortising intangible assets like patents, than in retail lending.
Bullet or balloon amortisation
Only interest is paid through the tenure, with the entire principal due as one lump sum at the end.
This shows up occasionally in commercial real estate loans and certain bond structures, but is uncommon for individual retail borrowers in India.
Negative amortisation
A situation, more than a deliberate method, where the installment does not even cover the full interest due.
The unpaid interest gets added back to the principal, so the loan balance grows instead of shrinking.
This is rare in India due to regulatory limits, but can occur on certain adjustable-rate products if rates rise sharply.
Quick comparison
| Method | How the payment behaves | Common use case |
|---|---|---|
| Equal installment (EMI) | Payment constant, interest-principal mix shifts | Home, car, and personal loans |
| Straight-line | Principal portion constant, total payment falls | Intangible asset accounting, some corporate loans |
| Bullet or balloon | Only interest paid until one final lump sum | Commercial loans, certain bonds |
| Negative amortisation | Balance can grow if payments miss full interest | Rare adjustable-rate products |
Key components of an amortisation schedule
- Principal. The original loan amount you borrowed, before any interest is added. Every row of the schedule works toward bringing this number down to zero.
- Interest rate. The annual rate charged by the lender, converted into a monthly rate to calculate each installment’s interest portion. For floating-rate loans, this can change, which forces the lender to recompute the rest of the schedule.
- Tenure. The total number of installments over which the loan is repaid. A longer tenure lowers the EMI but increases the total interest paid over the loan’s life.
- EMI. The fixed amount paid each period, calculated so that both principal and interest are fully cleared by the final installment.
- Interest-principal split. The changing share of each EMI that goes toward interest versus principal, heavily interest-weighted at the start and principal-weighted toward the end.
- Prepayment or foreclosure clause. The terms under which you can pay extra toward the principal, or close the loan early, and whether the lender charges a fee for doing so.
Benefits of loan amortisation
- Predictable budgeting. A fixed EMI means the same outflow every month for years, which makes it easy to plan a household budget around a home or car loan without surprises.
- Visible progress. An amortisation schedule shows, month by month, exactly how much of the loan has actually been repaid, rather than leaving the borrower to guess.
- Tax benefits on home loans. In India, the principal portion of a home loan EMI can qualify for deduction under Section 80C, and the interest portion under Section 24(b), up to the prescribed limits, which makes the interest-principal split from the schedule directly useful at tax filing time.
- Better prepayment decisions. Seeing exactly how much of a current EMI is interest versus principal helps a borrower judge whether prepaying now will save meaningfully more than waiting a few years.
Risks and limitations of amortisation
- Front-loaded interest. Early installments are mostly interest, so a borrower who exits a 20-year loan after five years has barely touched the principal, despite years of EMI payments.
- Total interest can be large. Stretching a loan over a longer tenure lowers the EMI but increases the total interest paid, sometimes to more than the original loan amount on very long tenures.
- Foreclosure charges may apply. Some lenders charge a fee for prepaying or closing a loan early, particularly fixed-rate loans, which can offset some of the interest saved. It is worth checking this clause before signing.
- Floating rates can reset the schedule. A rate hike on a floating-rate loan does not just change the EMI, it can extend the tenure if the EMI is kept fixed, so the schedule is worth rechecking whenever rates move.
Important: A common mistake is assuming that five years of EMIs on a 20-year loan means roughly a quarter of the principal is repaid. Because of front-loaded interest, the actual principal repaid is usually well below that, so check the real amortisation schedule rather than estimating
Frequently asked questions about amortisation
What does amortisation mean?
Amortisation means paying off a loan gradually through equal installments, where each payment covers part of the interest due and part of the principal, until the outstanding balance reaches zero.
The same word also applies in accounting, where it means spreading the cost of an intangible asset, such as a patent, evenly across the years it is expected to be useful.
How is amortisation calculated?
Amortisation is calculated using the loan amount, the interest rate, and the tenure to arrive at a fixed EMI through a standard formula.
Each month, interest is worked out on the remaining balance and subtracted from the EMI, and whatever is left repays principal.
Most bank websites and EMI calculators handle this automatically once you enter these three inputs.
What does amortisation of a loan mean?
Amortisation of a loan refers specifically to the gradual repayment of borrowed money through scheduled installments that include both interest and principal, rather than repaying the entire amount in one lump sum.
It is the standard structure behind nearly every home loan, car loan, and personal loan in India, and lenders are required to share the schedule once the loan is sanctioned.
What is amortisation called in Hindi?
Amortisation is usually translated in Hindi as “rin parishodhan” (ऋण परिशोधन), which literally means loan repayment or loan redemption.
In everyday banking conversations and loan paperwork in India, lenders and borrowers typically just use the English word, though financial literacy material aimed at non-English speakers sometimes uses the Hindi phrase instead, especially in rural banking and government scheme communication.
How does amortisation differ from depreciation?
Amortisation and depreciation both spread a cost over time, but they apply to different things.
Depreciation reduces the recorded value of a tangible asset, like machinery or a vehicle, to reflect wear and tear, while amortisation either repays a loan, or in accounting, spreads the cost of an intangible asset, like a patent or trademark, that has no physical form to wear out.
What affects my loan’s amortisation schedule?
Your amortisation schedule depends mainly on the loan amount, the interest rate, and the tenure you choose.
Any prepayment you make, or any rate change on a floating-rate loan, forces the lender to recalculate the remaining schedule, which is why it is worth requesting an updated schedule whenever either of those things happens.
Should I check my amortisation schedule before prepaying my loan?
Yes. Your amortisation schedule shows exactly how much of your current EMI goes toward interest versus principal, which tells you how much you would actually save by prepaying now rather than later.
Since interest makes up a much larger share of EMIs early in the loan, prepaying in the first few years generally saves more than prepaying closer to the end of the tenure.
If I’ve paid EMIs for five years on a 20-year loan, have I repaid a quarter of the principal?
Probably not, and this is one of the most common misconceptions about loans.
Because amortisation is front-loaded with interest, the principal repaid in the first five years of a 20-year loan is usually well below a quarter of the total, even though a quarter of the total payments have been made.
Checking the actual amortisation schedule is the only way to know the real figure.