What the Zero-Cost EMI Calculator does
This calculator shows what a "no-cost" or zero-interest EMI offer really costs you: it recovers the interest hidden in the offer, adds the GST charged on that interest each month, adds the processing fee and its GST, counts any cash discount you give up by not paying in full, and compares the total with paying upfront - in rupees and as an effective yearly rate.
No-cost EMI is a marketing label, not a kind of loan. The lender still charges interest; the seller either refunds it as an instant discount or has already built it into the price. The interest itself may cancel out, but on a credit-card EMI the GST on that interest does not, and neither does the processing fee. The difference is usually a few hundred rupees - small, but not zero, and worth knowing before you choose.
How to use it
- Choose how the offer works. Most marketplace offers give the interest back as a discount, so the instalments add up to the list price. If the EMI version costs more than paying in full, choose "interest built into the price".
- Enter the EMI price and tenure. For the discount structure, also enter the lender's interest rate - it is shown on the EMI options screen or the card issuer's EMI page.
- If paying in full gets a bigger discount (a bank offer on full payment, for example), enter that lower upfront price. For the built-in structure, enter the cash price.
- Choose how you pay. Credit-card EMIs attract GST on the interest; consumer-durable loans and most cardless EMIs do not, because loan interest is GST-exempt.
- Enter the processing fee, and check the GST rate. The page loads a dated rate; change it if your statement shows a different one.
- Read the extra cost at the top, the effective yearly rate, and the month-by-month table of interest, GST and what actually leaves your account.
Reading the results
The headline is the extra rupees over paying upfront. If it is a few hundred on a large purchase, the EMI may still suit you - the effective rate tells you whether spreading the cost is cheap or expensive money.
The effective cost is the yearly rate at which "keep the upfront price in your account now, pay the instalments later" breaks even. If your savings earn more than that rate after tax, keeping the cash and taking the EMI comes out ahead; if not, pay upfront.
A cash discount you lose by choosing the EMI is often the biggest single cost. A bank offer of 5% off for full payment outweighs the GST and fee on almost any no-cost EMI.
Worked example: a Rs 30,000 phone on a six-month credit-card no-cost EMI
The EMI is 30,000 / 6 = Rs 5,000. The card charges 15% a year, which is 1.25% a month, so the loan that six EMIs of Rs 5,000 can repay is 5,000 x (1 - 1.0125^-6) / 0.0125 = Rs 28,730.05. The seller's no-cost discount is the difference, Rs 1,269.95 - exactly the interest.
Month 1 interest is 28,730.05 x 1.25% = Rs 359.13, and GST at 18% on it is Rs 64.64. By month 6 the interest is Rs 61.73 and the GST Rs 11.11. Over the six months GST on interest totals 18% of 1,269.95 = Rs 228.59.
The Rs 199 processing fee carries Rs 35.82 GST, so it costs Rs 234.82.
In total you pay Rs 30,463.41 against Rs 30,000 upfront: Rs 463.41 more, about 1.5%. As a yearly rate on the money you keep in hand, that is roughly 5.4% - cheaper than most loans, but more than many savings accounts pay.
Formulas and scoring rules
- EMI
EMI = EMI price / n- Loan behind a discount-style offer
loan = EMI x (1 - (1 + i)^-n) / i, i = annual rate / 12 / 100The interest the seller refunds is EMI price - loan.- Rate hidden in a marked-up price
solve i from: cash price = EMI x (1 - (1 + i)^-n) / iSolved numerically; interest = EMI price - cash price.- Monthly interest and GST
interest_k = balance_(k-1) x i; GST_k = interest_k x GST rateGST on interest applies to credit-card EMIs only.- Processing fee
fee cost = fee x (1 + GST rate)- Extra cost
extra = EMI price + sum(GST_k) + fee cost - upfront price- Effective yearly cost
find r with upfront price = sum(payment_k / (1 + r)^k); effective = (1 + r)^12 - 1Figures are not rounded until display. Banks round each statement to the paisa, so their totals can differ by a few paise.
How this differs from the Loan EMI Calculator
The Loan EMI Calculator works out a monthly payment from a principal, a rate and a term. A no-cost EMI has no stated rate at all, so that calculation cannot tell you what it costs. This tool works backwards from the offer: it recovers the interest hidden in the discount or the price, adds GST on that interest and the processing fee, counts the cash discount you give up, and compares the whole thing with paying upfront.
Why GST appears on an interest-free EMI
Under the GST exemption for financial services, interest on loans is exempt, but the exemption expressly excludes interest involved in credit-card services. When a card issuer converts a purchase to an EMI, the interest is therefore taxable at 18%, and it is charged on your statement even though the seller has refunded the interest itself through the discount. The seller cannot refund the tax, because the tax is on the bank's service to you.
Consumer-durable loans from finance companies and many cardless EMI schemes are loans in the ordinary sense, so their interest is exempt; their processing fees are not. Check your sanction letter or the key fact statement to see which applies.
Limitations: what the result does not prove
- It applies the offer as you describe it. Pre-closure charges, late-payment fees, the effect of the EMI on your available credit limit and conditions such as a minimum cart value are not modelled.
- Banks round each statement and some charge GST on the fee in the month after purchase. Their figures can differ from these by small amounts.
- The GST rate and the exemption rules come from a dated file, not a live feed. Rates change by notification; check your statement.
- The effective rate compares cash flows only. It does not know what your savings earn, your tax rate or whether you would otherwise borrow at a higher rate - that comparison is yours to make. This is not financial advice.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- CBIC - GST rates for services
- CBIC Circular 102/21/2019-GST (quotes the interest exemption and its credit-card exclusion)
- Reserve Bank of India - Master Direction on credit card and debit card issuance and conduct
Frequently asked questions
Is no-cost EMI really free?
Usually not quite. The interest is refunded or built into the price, but on a credit-card EMI you still pay 18% GST on the interest, plus the processing fee and its GST. You may also give up a discount that only full payment gets. On a Rs 30,000 purchase over six months the extra is typically a few hundred rupees.
How is GST calculated on a no-cost EMI?
GST is charged on the interest component of each instalment, not on the whole EMI. Each month's interest is the outstanding balance times the monthly rate, so the GST is largest in month one and falls to almost nothing in the last month. The total is 18% of the total interest.
Why is GST charged on credit card EMI interest but not on a loan?
The GST exemption covers interest on loans and deposits but excludes interest involved in credit-card services. So interest on a card EMI is taxable at 18%, while interest on a consumer-durable loan from a finance company is exempt. Processing fees are taxable in both cases.
Should I choose no-cost EMI or pay the full amount?
Compare the extra cost with what the cash would earn while you keep it. If the effective yearly cost shown here is lower than your after-tax savings rate, the EMI is cheaper money; if paying in full earns a cash discount, paying upfront usually wins. The calculator shows both in rupees.
What is the processing fee on a no-cost EMI?
It is a one-time charge set by the bank or lender, commonly a couple of hundred rupees on card EMIs, and 18% GST is added to it. It usually appears on the first statement after the purchase. Enter the figure from the offer screen; the calculator adds the GST.
How do I find the interest rate in a no-cost EMI offer?
For a discount-style offer the bank's rate is listed on the EMI options screen. If the EMI price is simply higher than the cash price, choose "interest built into the price" and enter both prices: the calculator solves for the rate that turns the cash price into those instalments.
Last reviewed by the A2Z.Tools team against the sources listed above.
