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§01 · EDITORIAL · GLOSSARY · FLOATING-RATE-BOND

Floating-Rate Bond

A bond whose coupon rate resets periodically against a reference benchmark (91-day T-bill rate or MIBOR), reducing duration risk for investors compared to fixed-coupon bonds. RBI issues Floating Rate Savings Bonds (FRSB) directly to retail investors.

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Definition

A floating-rate bond (FRB, also called a variable-rate bond or floater) is a debt instrument whose coupon payment is not fixed at issuance but resets at predetermined intervals against a specified benchmark rate plus a spread:

Coupon(t) = Benchmark Rate(t) + Spread

where the spread is fixed at issuance and the benchmark resets each period (quarterly or semi-annually). Common benchmarks in India include: (a) the 91-day T-bill yield (RBI auction-determined, the conventional academic "risk-free rate" proxy for very short maturities); (b) MIBOR (Mumbai Interbank Offer Rate, administered by FBIL); and (c) the NSE MIBOR overnight rate for ultra-short instruments. The RBI issues Floating Rate Savings Bonds (FRSB) 2020 directly to retail investors — pegged at 35 bps above the National Savings Certificate (NSC) rate, currently resetting to 8.05% as of the most recent reset.

How it is computed

At each reset date, the new coupon is computed as: New Coupon = Benchmark + Contractual Spread. For a MIBOR-linked corporate bond with spread = +65 bps, if 3-month MIBOR resets to 6.80%, the next quarter's coupon = 7.45% annualised. Because the coupon adjusts toward current market rates at each reset, the bond's price stays close to par between reset dates — the interest rate risk (duration) is effectively capped at the time until the next reset, not the full maturity. Modified Duration of a floater ≈ time to next coupon reset (e.g., 0.25 years for quarterly reset), regardless of stated maturity. Post-reset, the duration "resets" to near zero again. SEBI's NCS Regulations 2021 require the reset mechanism, benchmark, spread, and reset frequency to be disclosed in the offer document.

Why it matters for investors

FRBs are the preferred instrument for investors who want bond-like credit exposure while avoiding duration/interest-rate risk: (1) Rising-rate environments: When RBI raises the repo rate, the T-bill benchmark rises, and FRB coupons automatically step up — protecting investors from the price erosion that fixed-coupon bond holders suffer. (2) Low mark-to-market volatility: Since MD ≈ time to next reset (often 0.25–0.5 years), NAV of floating-rate debt funds is nearly immune to rate moves. SEBI's Floater Fund category requires minimum 65% in floating-rate instruments. (3) Spread capture: Corporates issuing FRBs must offer a spread above the benchmark — AAA corporates typically at T-bill + 30–60 bps, AA+ at T-bill + 70–100 bps. (4) RBI FRSB retail access: RBI's FRSB 2020 is available through designated banks (SBI, nationalised banks, private banks) with no demat required — making floating-rate exposure accessible to retail investors.

Worked example

An investor holds ₹10 lakh face value of a 5-year Power Finance Corporation (PFC) AA+ FRB, resetting quarterly at 91-day T-bill + 75 bps. Reset history over 1 year:

Quarter91-day T-billCoupon (ann.)Quarterly cash received
Q16.75%7.50%₹18,750
Q26.85%7.60%₹19,000
Q36.60%7.35%₹18,375
Q46.80%7.55%₹18,875

Total year 1 interest = ₹75,000 (avg 7.50%). A comparable 5-year fixed-rate PFC bond at 7.70% would have earned ₹77,000 but would have also suffered ~4.12% capital loss if yields rose 100 bps. The FRB sacrifices a small coupon premium in exchange for near-zero duration risk.

Caveats

Benchmark discontinuation risk: If the reference rate benchmark (e.g., MIBOR) is reformed or discontinued (similar to LIBOR transition globally), fallback language in the bond indenture determines the replacement rate. Spread compression: In falling-rate cycles, fixed-rate bonds outperform floaters since coupon of floaters falls with the benchmark. Credit risk unchanged: FRBs eliminate duration risk but retain full credit risk — a floating-rate bond from a stressed issuer still carries default risk. Liquidity: FRBs are less liquid than benchmark fixed-rate G-Secs in the secondary market; retail investors may face wider spreads.

See also

Primary source

MintByte is registered with AMFI (ARN-314872) and APMI (APRN-01658). This glossary entry is for educational purposes only and does not constitute investment advice or a recommendation to buy or sell any security.

Reviewed · January 2026

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Glossary definitions are written for Indian capital allocators first; where US convention differs, the entry calls that out explicitly. MintByte is an AMFI-registered mutual fund distributor (ARN-314872); SEBI Registered Investment Adviser and Research Analyst registrations are in process. Not investment advice.