What it means
Banks lend money to each other every day to manage their cash balances. The rate at which they do this becomes a benchmark that many other products follow.
MIBOR is the Indian version of this idea, and it is quoted for the rupee. The overnight rate is calculated from actual transactions, and it is published by Financial Benchmarks India Private Limited, an independent administrator.
Older versions of the benchmark were based on quotes from banks, but the move to transaction-based calculation was designed to make it harder to manipulate. A benchmark has to be trusted, or the contracts that rely on it lose credibility.
In practice, a business with a floating-rate loan might agree to pay MIBOR plus a spread, such as 1.5%. Each period, the lender looks up the benchmark and adds the spread to calculate the interest due.
When MIBOR rises, the borrower pays more, and when it falls, the borrower pays less. MIBOR is also used in interest rate swaps (agreements to exchange fixed and floating interest payments).
A company that wants certainty can swap a floating MIBOR-linked payment for a fixed one. These swaps let treasurers manage the risk that rates move against them.
A point of nuance is that the benchmark follows the central bank's policy rate closely, but not exactly. Liquidity in the banking system and short-term demand for cash both push it above or below the policy rate.
Treasurers therefore watch both numbers. When reading a loan agreement, the details matter as much as the headline.
The contract should say which published rate applies, how often it resets, which day-count convention is used, and what happens if the benchmark is ever discontinued. Those fallback terms are easy to overlook until a benchmark changes.
In practice
Real-world examples.
Example
An Indian manufacturer takes a working capital loan priced at MIBOR plus 2%. When the central bank tightens policy and MIBOR climbs, the company's monthly interest cost rises. The treasurer budgets for the extra cost and considers fixing the rate with a swap.
Example
A mutual fund that holds floating-rate bonds linked to MIBOR sees its income rise as the benchmark increases. The fund manager explains to investors that income from these bonds adjusts upward with rates. The bonds' prices stay close to face value because the coupon resets.
Example
A multinational's Indian subsidiary enters a swap in which it pays a fixed rupee rate and receives MIBOR. This offsets the floating MIBOR it pays on its bank loan. The finance team now has a predictable interest bill for the next three years.
Formula
Calculation
Floating interest for a period = Principal x (MIBOR + Spread) x Days / 365
Suppose a company has a loan of INR 100,000,000, with an assumed MIBOR of 6.50% and a spread of 1.50%, so the rate is 8.00%. For a 90-day period the interest is 100,000,000 x 0.08 x 90 / 365. First 100,000,000 x 0.08 = 8,000,000. Then 8,000,000 x 90 = 720,000,000, and 720,000,000 / 365 = INR 1,972,603 (rounded). If MIBOR rises by 1 percentage point to 7.50%, the rate becomes 9.00% and interest for the same period rises to INR 2,219,178 (rounded).Case study
Seen in the real world.
Kaveri Textiles is an illustrative, fictional exporter with an INR 500,000,000 loan priced at MIBOR plus 1.8%. The finance director worries that rising rates will squeeze the company's thin margins, as interest already takes a notable share of operating profit.
She asks the bank for a quote on a swap converting the floating payments to a fixed rate of 8.9%. If MIBOR averages 6.5% over the loan's life, the company would pay about 0.6 percentage points more than it would have on the floating loan. The certainty is the product being bought.
In this illustrative case, the board approves a swap covering 60% of the loan. This gives the company protection against a sharp rise while leaving some benefit if rates fall. The finance director records the swap decision and the reasoning for the audit file. She also asks the bank to confirm in writing which published rate the swap references, so that the loan and the swap move together and no gap opens between them.
Watch out
Common mistakes.
- Assuming MIBOR is the same as the central bank's policy rate, when it is a market rate that can sit above or below it.
- Forgetting to check which version of the benchmark a contract references, such as overnight or a term rate.
- Ignoring the spread, which can make up most of the borrower's total cost.
Questions
People also ask.
Who publishes MIBOR?
An independent administrator, Financial Benchmarks India Private Limited, calculates and publishes the benchmark.
Why did the benchmark methodology change?
Rate-setting based on quotes was vulnerable to manipulation, so the system moved towards rates based on actual transactions.
How does MIBOR affect a borrower?
If the loan is linked to MIBOR, interest payments reset as the benchmark moves, rising when it rises and falling when it falls, while the agreed spread stays the same.
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