Fixed Rate vs Floating Rate Notes (FRNs)

Introduction

The standard US dollar IG bond pays a fixed coupon set at issuance and held constant for the life of the bond. A 2025 vintage 10-year IG benchmark might pay 5.05% semi-annually for ten years; a 30-year tranche might pay 5.625%. The fixed-rate format dominates IG issuance because it gives both the issuer and the investor predictable cash flows: the issuer locks in funding cost; the investor locks in income. But a meaningful slice of IG issuance happens in floating-rate format, where the coupon resets each quarter against a reference rate. Understanding when issuers choose floating over fixed, and what the floating-rate note (FRN) mechanics look like, is one of the cleanest tests of how a candidate thinks about bond structure.

This article walks through the fixed-versus-floating decision in detail. It covers the standard mechanics of each format, the reasons fixed-rate dominates IG issuance, the specific situations where FRNs make sense (FIG balance-sheet matching, short-tenor money-market issuance, rising-rate-environment investor demand), the post-LIBOR shift to SOFR as the reference rate, and the trade-offs each format presents to issuers and investors.

A fixed-rate IG bond pays the same coupon for its entire life, typically twice a year (semi-annual). The coupon level reflects the prevailing benchmark rate (the relevant Treasury yield at the time of issuance) plus the credit spread (the issuer's compensation premium for credit risk). Once set at issuance, the coupon does not change, and the issuer's funding cost is fully locked in.

Why Fixed-Rate Dominates IG

Fixed-rate is the default IG format for several structural reasons. Funding-cost certainty for issuers: a fixed-rate bond removes interest-rate risk from the issuer's perspective. The issuer knows exactly what its annual interest cost will be for the life of the bond, which simplifies multi-year capital planning. Income certainty for investors: fixed-rate bonds give investors predictable income, which matches the cash-flow needs of insurance and pension portfolios particularly well. Deeper investor base: the fixed-rate IG investor base (insurance, pension, mutual fund, sovereign wealth) is substantially larger than the floating-rate investor base, which means fixed-rate bonds typically attract more competitive pricing. Standard benchmark structure: fixed-rate bonds align with the major bond indices (Bloomberg US Aggregate, ICE BofA US Corporate Index), which require fixed coupon schedules for index inclusion.

The Trade-Off Investors Face

Fixed-rate bonds expose investors to interest-rate risk. When rates rise, the price of a fixed-rate bond falls because its fixed coupon becomes relatively less attractive than newly-issued bonds with higher coupons. The longer the tenor, the more sensitive the bond's price is to rate moves (longer-duration bonds have larger price moves for a given rate change). Investors holding to maturity collect the original coupon regardless of rate moves, but mark-to-market valuations swing with the rate environment.

A floating-rate note pays a coupon that resets each quarter (sometimes monthly) against a reference rate plus a fixed spread. The fixed spread is set at issuance based on the market's perception of the issuer's credit risk and does not change for the life of the bond. The reference rate is reset at the beginning of each coupon period and applied to compute that period's coupon.

The SOFR Transition

The reference rate for new US dollar FRNs is predominantly SOFR (Secured Overnight Financing Rate), which replaced LIBOR after the LIBOR cessation that completed in 2023. SOFR is published daily by the New York Federal Reserve and reflects the cost of borrowing overnight collateralized by US Treasury securities. Most FRN coupons use a compounded SOFR (averaged over the coupon period) plus the fixed spread, computed in arrears at the end of the period and applied to the coupon payment.

SOFR (Secured Overnight Financing Rate)

The benchmark interest rate that replaced US dollar LIBOR for most new US dollar floating-rate instruments after the LIBOR cessation completed in mid-2023. SOFR is published daily by the Federal Reserve Bank of New York and measures the cost of borrowing cash overnight collateralized by US Treasury securities, computed from actual transactions in the Treasury repo market (rather than the panel-bank survey methodology that LIBOR used). Floating-rate notes referencing SOFR typically use compounded SOFR over the coupon period plus a fixed credit spread; the compounded SOFR is computed in arrears and applied to the coupon payment at the end of the period.

Floating Rate Note (FRN)

A bond whose coupon resets periodically (typically quarterly, sometimes monthly) against a reference rate plus a fixed spread. The reference rate for new US dollar FRNs is predominantly SOFR (Secured Overnight Financing Rate) after the LIBOR cessation completed in 2023. The fixed spread is set at issuance based on the issuer's credit risk and does not change for the life of the bond; only the reference-rate component changes. FRNs have low duration (close to zero) because the coupon adjusts with rates, which means FRN prices remain relatively stable when rates move, in contrast to fixed-rate bonds where prices fall as rates rise.

Coupon Calculation Example

The FRN coupon resets each period to the reference rate plus a fixed credit spread:

The reference rate is typically SOFR (post-LIBOR transition) reset quarterly or semi-annually; the spread is set at issuance and stays constant for the life of the bond. A typical USD FRN might pay "compounded SOFR plus 50 basis points" with quarterly resets. If compounded SOFR for the period averages 4.30%, the coupon for that period $= 4.30\% + 0.50\% = 4.80\%$ (annualized), applied prorated for the quarter. The next quarter, if compounded SOFR averages 4.20%, the new coupon $= 4.20\% + 0.50\% = 4.70\%$. The issuer's funding cost moves with the reference rate, but the credit spread stays locked at 50 basis points throughout.

Discount Margin

The discount margin (DM) is the FRN equivalent of yield-to-maturity for fixed-rate bonds: the spread above the reference rate that prices the FRN to its current secondary market price, assuming the reference rate stays constant over the remaining life of the bond. DM lets investors compare FRNs across different reference rates, reset frequencies, and credit profiles on a common spread basis.

The decision to issue FRN format rather than fixed-rate is driven by specific issuer and market dynamics. Most IG issuance is fixed-rate; FRNs occupy a smaller but consistent share, with specific use cases driving the format choice.

FIG Issuer Balance-Sheet Matching

Banks and other financial institutions are the heaviest FRN issuers. The structural reason is balance-sheet matching: bank balance sheets carry primarily floating-rate assets (commercial loans, mortgages, credit card receivables, all priced over reference rates), and matching the asset side with floating-rate funding minimizes interest-rate risk exposure on the bank's net interest margin. A bank that issues fixed-rate debt and holds floating-rate assets effectively takes on duration mismatch, which the bank's treasury team would then have to swap out separately. Direct FRN issuance avoids the swap and aligns funding with the asset profile.

Short-Tenor Money-Market Issuance

FRN format dominates short-tenor IG issuance (1 to 2 year maturities). At short tenors, the duration risk of a fixed-rate bond is small, but money-market mutual funds, corporate treasury accounts, and other short-duration buyers prefer FRN format because the coupon resets keep the bond's market value close to par across rate environments. The structural fit is why most US Treasury FRN issuance and most corporate FRN issuance falls in the 2-year-and-under tenor range.

Investor Demand During Specific Rate Environments

FRN demand from broader investor accounts spikes during specific rate environments. When investors expect short-term rates to rise, FRNs become attractive because the coupon adjusts upward with the reference rate; when investors expect rates to fall, FRN demand shrinks. The 2022 to 2023 Fed rate-hike cycle drove substantial FRN issuance and investor inflows; the 2025 environment with the Fed cutting rates and broader market sentiment expecting further cuts has seen relatively modest FRN demand from non-FIG accounts.

The fixed-versus-floating decision is rarely binary on a benchmark deal. A frequent IG issuer often runs a multi-tranche deal that includes both fixed and floating tranches, letting investors with different preferences participate in the same execution. Meta's October 2025 $30 billion offering ran six tranches but all were fixed-rate; in contrast, a typical FIG deal from JPMorgan or Bank of America might combine both fixed and floating tranches: a 3-year fixed-rate tranche, a 3-year FRN tranche, a 5-year fixed-rate, and a 10-year fixed-rate, capturing demand from each investor pocket.

The fixed-versus-floating decision is one of the structural choices on every benchmark deal, and the format mix in any given year reflects the rate environment, the FIG share of total issuance, and the broader investor demand picture. The next article in this section covers the call structure that defines most fixed-rate IG bonds: the make-whole call, the bullet alternative, and the par-call window that bridges the two.