Flat rate vs reducing-balance rate
A flat rate charges interest on the original loan amount for the entire tenure, ignoring the fact that you repay principal every month. A reducing-balance rate charges interest only on what is still outstanding. Because the outstanding balance keeps falling, a flat rate of 10% costs roughly as much as a reducing rate of 18% on a 3-year loan. Two-wheeler, consumer durable, gold and some personal and vehicle loans are still quoted on flat rates, which is why they look cheap.
Conversion
Under a flat rate, total interest = P × flat rate × years and EMI = (P + total interest) ÷ months. The equivalent reducing rate is the rate at which the standard EMI formula produces the same EMI — the calculator solves this exactly by iteration. A handy approximation: Reducing ≈ Flat × 2n ÷ (n + 1), where n is the number of instalments.
Worked example
₹5,00,000 at 10% flat for 3 years: interest = 5,00,000 × 10% × 3 = ₹1,50,000, EMI = ₹18,056. The same EMI on reducing balance corresponds to a rate of about 17.9%. Had the bank actually charged 10% reducing, the EMI would be ₹16,134 and total interest only ₹80,800 — you pay ₹69,200 more because of the flat method. Conversely, a 12% reducing-rate loan over 5 years equals roughly 6.7% flat.
Why lenders quote flat rates
- The headline number looks much lower, which helps sales of consumer loans.
- RBI now requires the annualised reducing rate (APR) in the Key Fact Statement for all retail loans, so always ask for it.
- Dealer-financed vehicle loans and "0% EMI" schemes often hide a flat-rate structure plus processing fees.
Using the table
The tenure table shows how the gap widens with longer tenures: a flat rate converts to a higher reducing equivalent for 5 years than for 1 year, because principal stays outstanding longer under the reducing method. Use the converter before signing any loan whose rate "sounds too good".
Frequently Asked Questions
Is a flat rate loan more expensive?
Yes. For the same quoted number, a flat-rate loan costs almost twice as much interest as a reducing-balance loan over typical tenures.
How do I convert flat rate to reducing rate quickly?
Multiply the flat rate by about 1.8–1.9 for 2–5 year loans, or use the formula Reducing ≈ Flat × 2n ÷ (n+1). This tool gives the exact value.
Do banks quote home loans on flat rate?
No. Home loans, education loans and most bank personal loans are on reducing balance. Flat rates are common in two-wheeler, consumer durable and some NBFC loans.
Is a flat rate loan illegal?
No, but RBI requires lenders to disclose the equivalent annualised rate (APR) in the Key Fact Statement so borrowers can compare.
Disclaimer: This tool is for general information and estimation only. Tax rates and rules change — verify with official sources or a professional before acting. Read full disclaimer.