What Is an Interest Rate? The Benchmark Behind Your EMI

When RBI cuts the repo rate, how long before it reaches your home loan?

There is an answer, it sits in a circular from 2019, and it is precise: at least once in three months. Not "quickly", not "typically monthly or quarterly", not "banks usually pass it on". A maximum delay, written down.

We read twenty-two pages explaining interest rates, six of them from Indian lenders writing specifically about repo rates and home loans. None states it. None names the circular. None lists the four benchmarks a bank may use. And none mentions that the rule binds banks but not housing finance companies, which is the difference between two borrowers seeing the same cut arrive at different speeds.

One of those pages, from a large Indian bank, still reports the repo rate as 6.50% and unchanged since April 2023. It is 5.25%.

What follows covers what an interest rate is, how the number on your loan is assembled, and the benchmark regime that decides when it moves.

What is an interest rate?

An interest rate is the price of borrowing money, expressed as a percentage of the principal and usually quoted per year. The same number runs in both directions: what a lender charges on a loan, and what a bank pays on a deposit, because in both cases someone is using money belonging to someone else.

The quoted rate alone does not tell you the cash cost. That depends on the balance the rate applies to and how often it is applied. A loan repaid monthly charges interest on a shrinking balance, so the rupees paid come to less than the headline rate on the original sum implies.

Two neighbouring numbers get confused with this one. Compound interest describes what happens when interest is added to the balance and then earns interest itself, which our compound interest explainer covers. APR folds compulsory fees into a single annual figure, and what it includes and leaves out is a separate subject with its own regulation. This post is about the rate itself.

How is the rate on your loan assembled?

A consumer rate is a benchmark plus a spread, and the two parts move for entirely different reasons.

Layer	What it is	Who controls it
Benchmark	The published rate the loan is tied to	The central bank or a benchmark administrator
Operating cost	The lender's cost of running the business	The lender, within limits
Credit risk premium	The lender's view of your specific risk	The lender, based on your record
Competition	What rivals are offering	The market

That structure explains something borrowers find puzzling. A repo cut of 25 basis points need not move your rate by 25 basis points, because only the first layer changed. It also explains why two borrowers at the same bank, on the same product, in the same week, are quoted differently: the benchmark is identical and the credit risk premium is not.

On Indian external-benchmark loans, RBI constrains how far the spread can drift. The credit risk premium may change only when the borrower's credit assessment undergoes a substantial change, and other components including operating cost may be altered only once in three years. So a lender cannot quietly widen its margin to swallow a rate cut.

What is India's external benchmark rule?

Since 1 October 2019, Indian banks must link every new floating-rate retail loan to an external benchmark, under RBI circular RBI/2019-20/53 dated 4 September 2019. It covers new floating-rate personal and retail loans, including housing and auto, and floating-rate loans to micro and small enterprises.

Four benchmarks are permitted:

Permitted benchmark	Published by
RBI policy repo rate	Reserve Bank of India
3-month Government of India Treasury bill yield	Financial Benchmarks India (FBIL)
6-month Government of India Treasury bill yield	FBIL
Any other benchmark market rate published by FBIL	FBIL

Most banks chose the repo rate, which is why "repo linked lending rate" appears on so many sanction letters. A bank must use a uniform benchmark within a loan category, so it cannot run two benchmarks on one product for different customers.

Then the provision nobody publishes, in RBI's own words: the interest rate under external benchmark shall be reset at least once in three months.

Read that as a ceiling on delay. A bank may reset faster, and some do. What it cannot do is leave your rate untouched for a year after the benchmark has moved.

Three limits on the rule matter, and none appeared on any page we read.

It binds banks, not everyone. The circular is addressed to scheduled commercial banks excluding regional rural banks, small finance banks, and local area banks. Housing finance companies and NBFCs sit outside it. If your home loan came from an HFC, this reset ceiling does not apply to you.

It applies to new loans from October 2019. Existing loans on MCLR, the base rate or BPLR continue on those terms until repaid or renewed, with a switchover route for borrowers already entitled to prepay a floating loan without charge.

MCLR still exists. It is an internal benchmark, computed by the bank from its own cost of funds, and RBI's stated reason for the 2019 change was blunt: internal benchmarks such as the base rate and MCLR had not delivered effective transmission of monetary policy. A bank controls its own MCLR. It cannot control the repo rate.

One competitor page inverts this exactly, telling readers that under MCLR banks must adjust as soon as the repo rate changes. The opposite is true, and it is the reason the regime changed.

What are the benchmark rates right now?

RBI's policy repo rate was 5.25% and the US federal funds target range 3.50% to 3.75% when this post was checked on 21 July 2026. Both move on their own schedules, so treat these as a dated snapshot.

Rate	Level	As at
RBI policy repo rate	5.25%	21 July 2026
RBI standing deposit facility	5.00%	21 July 2026
RBI marginal standing facility and bank rate	5.50%	21 July 2026
MCLR, overnight, across banks	7.80% to 8.00%	21 July 2026
Base rate, across banks	8.40% to 10.00%	21 July 2026
US federal funds target range	3.50% to 3.75%	Set 17 June 2026

The gap between the repo rate and the MCLR band in that table is the argument for external benchmarking in a single line. Both are benchmarks. One is published by the central bank and one is computed by the lender, and they sit roughly two and a half percentage points apart.

RBI's own research recorded what the switch achieved. External-benchmark-linked loans rose from 2.4% of outstanding loans in September 2019 to 28.5% by March 2021, and weighted average lending rates fell 222 basis points on other personal loans, 208 on vehicle loans and 194 on MSME loans between October 2019 and February 2022. Deposit rates moved too, with the median savings deposit rate down 60 basis points over a comparable period. Transmission runs both ways.

Fixed or floating: what actually differs?

A fixed rate stays put for the life of the loan, and a floating rate moves with its benchmark. The trade is certainty against participation.

	Fixed	Floating
Payment predictability	Full	Changes with the benchmark
If policy rates fall	You keep paying the old rate	Your rate falls, within the reset window
If policy rates rise	You are insulated	Your rate rises
Reset discipline in India	None applicable	At least once in three months, bank loans
Common use in India	Personal loans	Home loans

A second Indian rule is worth knowing, from RBI's directions of 18 August 2023, updated 1 October 2025, which bind a wider set including NBFCs and housing finance companies. When a floating rate resets upward, the borrower shall be given the choice between a higher EMI, a longer tenor, or a combination, plus the option to prepay in part or in full at any point. Lenders must also send a quarterly statement showing principal and interest recovered, the EMI, the number of EMIs remaining and the annualised rate.

Switching from floating to fixed is at the lender's option under its board-approved policy. The EMI-versus-tenor choice is not optional for the lender to offer.

One competitor page describes that choice as something "some financial institutions allow", with terms that vary. It is a regulated entitlement.

Why do two lenders quote the same rate differently?

Because a rate can be quoted on the original amount or on the falling balance, and the same percentage produces very different costs.

On a reducing-balance loan, interest each period applies to what is still outstanding, so the rupee cost falls as you repay. On a flat-rate quote, interest is computed on the original principal for the whole tenor, which makes an identical headline number substantially more expensive.

This is the point where the rate stops being comparable and APR takes over, since APR is defined to capture the full compulsory cost on a common basis. Our APR explainer covers what that calculation includes and, more usefully, what regulation leaves out of it.

For card balances, where the rate is usually quoted monthly and compounds daily, how credit card interest works carries the mechanics and the current Indian rate band.

What this post deliberately does not cover

This explains what an interest rate is and how the number on an Indian loan is set. It does not recommend fixed or floating, a lender, or a product, and the tables describe rules instead of arguing for a choice.

Several adjacent subjects sit elsewhere on purpose. What APR adds to a rate, and the fees regulation excludes from it, is in the APR explainer. How interest compounds is in compound interest. Card mechanics are in how credit card interest works, and the personal loan as a product, including its fees, is in what a personal loan is.

Two limits on the figures. Every rate here carries the date it was checked, 21 July 2026, and all of them will move; RBI's current-rates panel and the Federal Reserve's policy pages are where to re-check. And this post offers no forecast of where rates go next, because nobody credible publishes one worth repeating.

Borrowing decisions turn on tenure, income and circumstances no article can see. A qualified financial adviser is the right place for a decision that depends on your own numbers.

Frequently asked questions

What is an interest rate in simple terms? An interest rate is the price of borrowing money, expressed as a percentage of the amount borrowed and usually quoted for a year. The same number works in both directions: it is what a lender charges you on a loan and what a bank pays you on a deposit, because in both cases someone is using money that belongs to someone else. What the percentage costs in cash depends on the balance it applies to, which is why a loan you repay monthly costs less in rupees than the headline rate on the original sum suggests.

What is the difference between a fixed and a floating interest rate? A fixed rate stays the same for the life of the loan, so the payment is predictable and does not move when policy rates do. A floating rate is tied to a benchmark and moves with it. In India that benchmark is external and named: since 1 October 2019, RBI has required banks to link new floating-rate retail loans to one of four permitted external benchmarks, most commonly the policy repo rate. The trade is straightforward. Fixed buys certainty, and floating passes both cuts and rises through to you.

How quickly does an RBI repo rate cut reach my home loan? Within three months at most, if the loan is a floating-rate loan from a bank. RBI's external benchmark circular of 4 September 2019 states that the interest rate under an external benchmark shall be reset at least once in three months. That is a ceiling on the delay and not a promise of speed, so a bank may reset faster. Two conditions matter. The rule covers banks, small finance banks and local area banks, not housing finance companies or NBFCs. And it applies to new floating-rate loans from 1 October 2019, so older loans linked to MCLR or the base rate continue on those terms until switched or repaid.

Which benchmarks can an Indian bank use for a floating-rate loan? Four, under RBI's 2019 circular: the RBI policy repo rate, the three-month Government of India Treasury bill yield published by Financial Benchmarks India, the six-month Treasury bill yield published by the same body, or any other benchmark market rate FBIL publishes. Most banks chose the repo rate, which is why repo-linked lending rate appears on so many sanction letters. One constraint is worth knowing: a bank must adopt a uniform benchmark within a loan category, so it cannot run two different benchmarks on the same product for different customers.

Who actually decides the rate on my loan? Your lender does, inside a structure the central bank influences without controlling. The benchmark sets a floor that moves with policy. On top of it the lender adds a spread covering its operating cost and its view of your credit risk, and that spread is where competition and your own record show up. RBI limits how the spread can move on external-benchmark loans: the credit risk premium may change only when the borrower's credit assessment changes substantially, and other components including operating cost may be altered only once in three years.

Why did RBI move banks off MCLR to an external benchmark? Because internal benchmarks were not passing policy changes through to borrowers. RBI's circular states the reason plainly: internal benchmarks such as the base rate and MCLR had not delivered effective transmission of monetary policy. An internal benchmark is computed by the bank from its own cost of funds, which leaves it discretion over the timing and size of any change. An external benchmark is published by someone else, so the bank cannot manage it. RBI's own research recorded the effect: the share of outstanding loans linked to external benchmarks rose from 2.4% in September 2019 to 28.5% by March 2021.

Sources

• Reserve Bank of India, External Benchmark Based Lending, RBI/2019-20/53, 4 September 2019 (the four permitted benchmarks, the uniform-benchmark rule, the three-month reset ceiling, the spread constraints, the institutions covered, and RBI's stated reason for moving off internal benchmarks) rbi.org.in

• Reserve Bank of India, Reset of Floating Rate EMI based Personal Loans, RBI/2023-24/55, 18 August 2023, updated 1 October 2025 (the borrower's mandatory choice between a higher EMI, a longer tenor or a combination, the right to prepay, and the quarterly statement requirement) rbi.org.in

• Reserve Bank of India, current rates, read 21 July 2026 (policy repo rate, standing deposit facility, marginal standing facility, bank rate, and the MCLR and base rate bands across banks) rbi.org.in

• Reserve Bank of India, Monetary Transmission to Banks' Interest Rates: Implications of External Benchmark Regime, RBI Bulletin (the external-benchmark share rising from 2.4% to 28.5%, and the weighted average lending rate declines by loan category) rbi.org.in

• Board of Governors of the Federal Reserve System, FOMC calendars and statements (the federal funds target range maintained at 3.50% to 3.75% on 17 June 2026) federalreserve.gov