What it means
A floating-rate instrument is usually priced as a benchmark plus a margin, for example LIBOR plus 1.50%. When the margin is zero, the instrument is said to be at LIBOR flat, meaning the holder earns or pays the benchmark and nothing more.
Lenders accept a zero margin only when they see the borrower as being about as safe as the panel of banks that set the benchmark. A top-rated borrower or a very short, well-secured loan might be priced this way, while weaker borrowers pay a positive spread.
In swaps, LIBOR flat is the standard way of describing the floating leg. A dealer might quote a swap in which one party pays a fixed rate and receives LIBOR flat, which keeps the floating side clean so the fixed rate carries all the pricing.
The idea is also used to compare funding costs. If a bank can raise money at LIBOR flat, it earns profit only on the margin it charges borrowers above that level.
A common nuance is that "flat" refers only to the spread, not to the level of the rate. LIBOR flat can be 0.5% in one year and 5% in another, so the cost of such a loan still moves with the market.
Market practice also uses the phrase in secondary trading. An investor who buys a floating-rate note at LIBOR flat accepts only the benchmark return, so the investment must be justified by safety or liquidity and not by extra yield.
When a note trades at a positive spread, the market is demanding extra compensation for credit risk.
In practice
Real-world examples.
Example
A bank lends $8,000,000 to a highly rated utility at LIBOR flat for a 90-day bridge facility. The bank earns only its cost of funds, so it agrees only because it expects fee income from the utility's other business.
Example
A swap dealer quotes a client a three-year swap in which the client pays a fixed rate and receives LIBOR flat. The client can then compare the fixed rate directly against the interest it pays on its floating-rate loan.
Example
A fund manager buys a floating-rate note priced to yield LIBOR flat. The price shows the market sees the issuer as having credit quality similar to the banks behind the benchmark, so the note should trade close to its face value.
Formula
Calculation
Floating interest = Notional x (LIBOR + Spread) x Days / 360
Suppose a $10,000,000 loan runs for one 90-day period with LIBOR at 2.00%. At LIBOR flat the spread is zero, so interest = 10,000,000 x 0.0200 x 90 / 360 = $50,000. If the loan were priced at LIBOR plus 0.50%, interest = 10,000,000 x 0.0250 x 90 / 360 = $62,500. The $12,500 difference is the value of the 0.50% spread for that quarter. The calculation shows why even a small spread matters at scale. On a $10,000,000 loan, each 0.10% of margin is worth about $2,500 a quarter, so negotiating the spread to zero can save real money.Case study
Seen in the real world.
Meridian Containers is an illustrative, fictional shipping company with a $12,000,000 revolving loan priced at LIBOR plus 1.25%. When its credit rating improves, the finance team negotiates to lower the margin to LIBOR flat, hoping to save on interest.
At a quarterly LIBOR of 2%, the saving on one 90-day period is 12,000,000 x 0.0125 x 90 / 360 = $37,500, or $150,000 over a full year at that rate. The bank agrees after the firm commits to route more payments through its accounts. The invented example shows that a zero margin is a prize earned by credit strength.
The saving is real, but the negotiation had a price. Meridian gave the bank a commitment to keep $3,000,000 of average balances on deposit, and its treasurer weighed the lost interest on that cash against the interest saved on the loan before agreeing.
Watch out
Common mistakes.
- Reading "flat" as meaning the interest rate does not change. It only means no spread is added, and the benchmark still moves.
- Assuming any borrower can obtain LIBOR flat. Only very strong credits, or heavily secured loans, are priced with no margin.
- Confusing LIBOR flat with a zero interest rate. The borrower still pays the full benchmark rate.
Questions
People also ask.
What does LIBOR plus a spread mean?
It means the rate is the benchmark plus an agreed margin that reflects the borrower's credit risk.
Is LIBOR flat still used?
The benchmark has been phased out, but "flat" is still used for zero-margin pricing over its replacement rates.
How does it differ from a floating rate note at a discount?
A discounted note is priced below its face value to compensate for a higher credit risk, whereas LIBOR flat describes a zero margin on the coupon.
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