Flat Rate vs Reducing Balance Calculator
Convert flat interest rate to reducing balance equivalent. Expose true cost of dealer finance and NBFC loans. A 10% flat rate equals 18.7% reducing balance for 5-year loan.
Flat Rate vs Reducing Balance EMI Calculator
Results update instantly
Enter the loan amount to compare
Enter the flat rate quoted by the lender
These numbers are a solid starting point. Your actual EMI may vary slightly by lender — always confirm before signing.
| Year | EMI Paid | Principal Paid | Interest Paid | Interest % | Balance |
|---|
A flat rate of 10% on a ₹10L loan for 5 years equals approximately 18.7% on a reducing balance basis. Many vehicle dealers and informal lenders quote flat rates — always ask for the reducing balance equivalent. RBI mandates banks to disclose APR (Annual Percentage Rate) — always compare on APR.
What is a Flat Rate vs Reducing Balance Calculator?
This flat rate vs reducing balance calculator helps you understand the true cost of a loan when the lender quotes a "flat rate" and converts it to the equivalent reducing balance rate — the method used by all RBI-regulated banks. Many borrowers are misled by flat rate quotes because a 10% flat rate sounds lower than a 15% reducing balance rate, but actually costs significantly more.
Enter the loan amount, the flat interest rate quoted by the lender, and the tenure. The calculator shows the actual EMI, the equivalent reducing balance rate, and total interest — exposing the true cost of flat-rate loans.
Flat rate vs reducing balance: the key difference
Flat EMI = (Principal + Total flat interest) ÷ Total months
Reducing balance interest: Calculated on outstanding principal each month
Reducing EMI: Standard formula P × r × (1+r)ⁿ ÷ ((1+r)ⁿ – 1)
For a ₹10L loan at 10% flat for 5 years: Total flat interest = ₹5L, EMI = ₹25,000/month. Equivalent reducing balance rate = approximately 18.7%. The loan that looks "10% interest" actually costs 18.7% on a reducing basis.
Conversion table: flat to reducing rates
As a general approximation, multiply the flat rate by 1.83 for 1-year loans, 1.87 for 3-year loans, and 1.92 for 5-year loans to get the approximate reducing balance equivalent. Our calculator performs the exact IRR calculation for your specific inputs.
Where flat rates are commonly used in India
Two-wheeler finance: Dealer-arranged bike loans frequently quote flat rates in advertising. "Only ₹1,500/month at 8% flat" sounds very different when you know the true rate is 14.5% reducing.
Consumer durables loans: Zero-cost EMI on electronics and appliances is usually a flat rate scheme where the interest is recovered via a higher product price or subvention from the brand.
Microfinance: MFI loans routinely use flat rates. A 26% flat rate from an MFI equals approximately 48% on reducing balance — understand this before taking such loans.
ThriftRupee tips for comparing loans
Tip 1: Always ask for the reducing balance rate. RBI mandates that banks quote interest on a reducing balance basis. If anyone quotes a flat rate, convert it using this calculator before comparing.
Tip 2: Check the APR. The Annual Percentage Rate (APR) includes all costs — interest plus processing fee plus other charges — expressed as a reducing balance rate. APR is the only truly comparable number across lenders.
Tip 3: Be especially careful with NBFCs and dealer finance. These are not always covered by the same RBI disclosure mandates as banks. Always ask: "What is the reducing balance equivalent rate?" before signing any loan agreement.