Direct Answer
Fixed-rate debt carries an interest rate that stays constant for the life of the borrowing, giving predictable payments but no benefit if market rates fall. Floating-rate debt has an interest rate that resets periodically based on a reference rate, such as SOFR, so interest expense rises and falls with market rates. Companies disclose the mix of fixed versus floating rate debt in footnotes, and that split is a key input to assessing a company's interest rate risk exposure.
Key Takeaways
- Fixed-rate debt locks in one interest rate for the life of the borrowing - the payment is predictable, but the company gets no relief if market rates decline.
- Floating-rate debt resets periodically off a reference rate, commonly SOFR, so the interest payment moves as market rates move.
- Companies disclose their fixed-versus-floating debt mix in the debt footnote, usually alongside a schedule of individual borrowings.
- The fixed/floating split is a core input for assessing interest rate risk exposure - it doesn't tell you whether the company is safe or risky on its own.
- A larger floating-rate share generally means more interest expense sensitivity to rate changes, but the practical impact varies by industry, hedging, and overall leverage.
What Is Fixed vs. Floating Rate Debt?
Every interest-bearing borrowing a company carries - a bond, a term loan, a revolving credit facility - has to specify how its interest rate is set. Fixed-rate debt sets that rate once, at issuance, and it stays constant for the life of the borrowing regardless of what happens to market interest rates afterward. If a company issues a bond at a fixed 6% coupon, it pays 6% whether market rates rise to 9% or fall to 3% over the life of that bond.
Floating-rate debt (also called variable-rate debt) works differently: its interest rate resets periodically based on a reference rate, such as SOFR (the Secured Overnight Financing Rate), plus a fixed spread agreed at issuance. The spread itself doesn't change, but the reference rate component does, so the total rate - and the resulting interest payment - rises and falls with the reference rate at each reset date.
Neither structure is universally better. Fixed-rate debt trades payment predictability for the risk of paying an above-market rate if rates later fall. Floating-rate debt trades that predictability away in exchange for automatically benefiting when rates fall - and automatically costing more when rates rise. Which one suits a given company depends on its cash flow stability, its own view on rates, and how much unpredictability in interest expense it can tolerate.
How Does a Floating Rate Reset?
A floating-rate borrowing is typically structured as reference rate + spread. The spread is fixed for the life of the loan and reflects the lender's assessment of the borrower's credit risk at issuance. The reference rate - commonly SOFR for U.S. dollar borrowings today - is a market rate that moves on its own, independent of the borrower.
At each reset date (the frequency varies by instrument - common conventions are monthly, quarterly, or another interval set in the loan agreement), the interest rate for the next period is recalculated using the then-current reference rate plus the fixed spread. The borrower's interest expense for that period then reflects the new rate. Fixed-rate debt has no such reset mechanism - the rate set at issuance is the rate for every remaining payment period until maturity.
Fixed vs. floating at a glance
| Feature | Fixed-rate debt | Floating-rate debt |
|---|---|---|
| Rate set | Once, at issuance, for the life of the borrowing | Resets periodically off a reference rate plus a fixed spread |
| Payment predictability | High - each payment is known in advance | Lower - payment changes as the reference rate changes |
| If market rates fall | No benefit - rate stays at the original level | Interest expense falls at the next reset |
| If market rates rise | No added cost - rate stays at the original level | Interest expense rises at the next reset |
| Common reference rate | Not applicable | Commonly SOFR (Secured Overnight Financing Rate) |
Worked Example
Hypothetical example - for education only. Suppose a company carries $100 million of debt: $60 million is a fixed-rate bond at a 6% coupon, and $40 million is a floating-rate term loan priced at SOFR + 2%, with SOFR currently at 4%.
Fixed-rate portion: $60M x 6.0% = $3.60M annual interest
Floating-rate portion: $40M x (4.0% + 2.0%) = $2.40M annual interest
Total annual interest expense = $6.00MNow suppose SOFR rises by 1 percentage point, to 5%, and the floating-rate loan resets at the new rate. The fixed-rate portion is unaffected.
Fixed-rate portion: $60M x 6.0% = $3.60M (unchanged)
Floating-rate portion: $40M x (5.0% + 2.0%) = $2.80M (up from $2.40M)
Total annual interest expense = $6.40MA 1-percentage-point rise in SOFR added $0.40 million to this company's annual interest expense - entirely from the floating-rate portion, since the fixed-rate bond's payment did not move. If this company instead carried all $100 million as floating-rate debt, the same 1-point rate move would have added roughly $1.00 million rather than $0.40 million, illustrating why the fixed/floating mix - not just the total debt figure - matters for interest rate risk.
Why the Fixed/Floating Mix Matters
Two companies with identical total debt loads can have very different interest rate risk depending on this split. A company funded mostly with fixed-rate debt has largely locked in its interest expense for years, which can make cash flow more predictable and easier to plan around - useful for a company with its own volatile revenue, since it doesn't need to also absorb unpredictable interest costs. A company funded mostly with floating-rate debt has interest expense that moves with the broader rate environment, which can help when rates are falling but adds pressure when rates are rising.
Assessing this exposure commonly starts with the debt footnote, where companies disclose the fixed-versus-floating breakdown, often alongside the reference rate and spread for each floating instrument and the maturity schedule. From there, the relevant questions vary by company and industry: how large is the floating-rate share relative to total debt and relative to operating cash flow, has the company hedged any of that floating exposure with interest rate swaps or caps, and how much cushion does its cash flow provide if interest expense rises. None of this reduces to one universal threshold - what counts as a manageable floating-rate share for a stable, cash-generative business can be a real risk for a highly leveraged or cyclical one.
Common Mistakes and Limitations
| Mistake | Why it causes problems | Better practice |
|---|---|---|
| Looking only at total debt, not the fixed/floating mix | Two companies with the same total debt can have very different interest rate risk depending on how much is floating. | Check the debt footnote for the fixed-versus-floating breakdown, not just the aggregate debt figure. |
| Ignoring interest rate hedges | A company can carry floating-rate debt on paper but have swapped much of that exposure to a fixed rate through a derivative, which the footnote breakdown alone may not make obvious. | Read footnote disclosures on interest rate swaps or caps alongside the fixed/floating debt split. |
| Applying one universal "safe" floating-rate percentage | What is a manageable floating-rate share varies by industry, cash flow stability, and overall leverage - there is no single threshold that applies to every company. | Evaluate the floating-rate share in the context of the specific company's cash flow variability and leverage, not against a fixed rule of thumb. |
| Assuming fixed-rate debt has no risk | Fixed-rate debt avoids interest rate risk but doesn't avoid refinancing risk - if it matures during a period of higher rates, the company may have to refinance at a materially higher fixed rate. | Check maturity schedules alongside the fixed/floating split, not the split in isolation. |
Glossary
- Fixed-rate debt - a borrowing whose interest rate is set at issuance and stays constant for its life.
- Floating-rate debt - a borrowing whose interest rate resets periodically based on a reference rate plus a fixed spread.
- SOFR - the Secured Overnight Financing Rate, a commonly used reference rate for floating-rate borrowings.
- Spread - the fixed margin added to a reference rate to set a floating borrowing's total interest rate.
- Interest rate risk - the risk that a change in market interest rates affects a company's interest expense or the value of its debt.
Frequently Asked Questions
What is the difference between fixed and floating rate debt?
Fixed-rate debt carries an interest rate that stays constant for the life of the borrowing, so the interest payment is predictable regardless of what happens to market rates afterward. Floating-rate debt has an interest rate that resets periodically based on a reference rate, such as SOFR, so the interest payment rises and falls as market rates move.
Why would a company choose floating-rate debt over fixed-rate debt?
Floating-rate debt often starts with a lower spread-adjusted rate than a comparable fixed-rate borrowing and lets a company benefit if market rates fall. The tradeoff is that interest expense is not predictable - it rises if the reference rate rises, which is why the choice depends on a company's own view of rates, its cash flow variability, and whether it can tolerate an unpredictable interest expense.
Where can I find a company's fixed versus floating rate debt mix?
Companies commonly disclose the mix of fixed versus floating rate debt in the debt footnote of their financial statements, typically alongside a schedule of individual borrowings, their interest rates, reference rates and spreads for floating instruments, and maturity dates. This footnote is the primary source for assessing a company's interest rate risk exposure.
What is SOFR and why does it matter for floating-rate debt?
SOFR (Secured Overnight Financing Rate) is a commonly used reference rate that floating-rate borrowings are indexed to. A floating-rate loan is typically priced as the reference rate plus a fixed spread, so when SOFR moves, the borrower's interest expense moves with it at the next reset date, even though the spread itself stays fixed for the life of the loan.
Does a company with more floating-rate debt have more risk?
A larger share of floating-rate debt generally means more exposure to rising market rates, since interest expense on that portion is not locked in. Whether that translates into meaningfully more risk varies by industry and by the company's broader financial position - factors like whether the debt is hedged with interest rate swaps, how much cash flow cushion the company has, and overall leverage all affect how much a floating-rate mix actually matters.
How do interest rate swaps change the effective mix?
A swap converts the economic character of debt without changing its legal form, so a company with fixed-rate bonds and a pay-floating swap has floating exposure that the debt footnote's instrument list does not show. The derivative footnote and the market risk disclosure describe the net position. Analysing the mix from instrument types alone therefore misreads companies that hedge.
What determines a company's preferred mix?
Considerations include whether revenues are correlated with rates, the shape of the yield curve at the time of issuance, covenant requirements, and treasury policy. A company whose revenue rises with rates can carry more floating exposure comfortably. The mix is a deliberate treasury decision rather than an accident of what was available.
How is a reference rate change disclosed and what does it affect?
Floating-rate instruments reference a benchmark, and the transition away from older benchmarks required amending contracts to reference replacement rates, which companies disclosed as it occurred. The effect on interest cost depends on the spread adjustment applied. This is a documentation change rather than an economic one, though the spread adjustment can shift the effective rate modestly.
How much can a rate move change interest expense for a floating-heavy borrower?
The effect is roughly the rate change multiplied by the floating balance, which for a company with substantial floating debt can be a material share of operating profit. Market risk disclosures often quantify the effect of a specified rate change. Comparing that figure against operating profit indicates how much of the company's earnings is exposed to rates.