# Interest Rate Hedging: Swaps, Caps, Collars and FRAs

Source: https://gravam.com/blog/interest-rate-hedging-swaps-caps-collars
Author: Tan Gravam
Published: 2026-07-24
Reviewed: 2026-08-02
Summary: The instruments treasury uses to hedge interest rate risk — swaps fix the rate, caps insure against rises, collars fund the cap, FRAs lock a single period.

**The main instruments treasury uses to hedge interest rate risk are swaps, caps, floors, collars and forward rate agreements.** A **swap** exchanges floating-rate payments for fixed, locking the rate. A **cap** is an option that pays out when rates rise above a strike — insurance against rising rates. A **floor** is its mirror for an investor. A **collar** combines the two to fund the protection. An **FRA** locks a rate for one future period. Each shapes the same underlying exposure differently, and — as with [FX instruments](https://gravam.com/blog/fx-hedging-instruments-forwards-options-swaps) — the point is to offset a real exposure, not to take a view on rates for its own sake.

_(This describes what the instruments do and how they hedge — it isn't a recommendation to use any particular one.)_

## The exposure, recapped

Floating-rate debt is the classic problem. You borrow at a [reference rate](https://gravam.com/blog/interest-rate-benchmark-reform-libor-sofr) plus a margin, and every time the reference resets your interest cost moves with it — a rise in rates lifts your cost with no cap on how far it goes. That's the core of [interest rate risk in corporate treasury](https://gravam.com/blog/interest-rate-risk-in-corporate-treasury): your borrowing cost, or your investment income, is at the mercy of a rate you don't control. The instruments below don't remove that exposure — they let you **fix** it, put a **ceiling** on it, or **shape** it into something you can live with.

## Swaps: fixing the rate

An **interest rate swap** exchanges one interest stream for another on a notional amount, under the [ISDA documentation](https://gravam.com/blog/isda-csa-and-collateral-management) that governs such over-the-counter trades. The common corporate case is the **payer swap**: you pay fixed and receive floating. Run against a floating-rate loan, the floating leg you receive cancels the floating interest you owe on the loan, and you're left paying a net fixed rate.

- **Gives:** an effective fixed rate — certainty on your interest cost.
- **Costs:** no upfront premium.
- **Trade-off:** it's an _obligation_. If rates fall, you keep paying the fixed rate and forgo the saving. Certainty cuts both ways — the same trade-off a [forward](https://gravam.com/blog/fx-hedging-instruments-forwards-options-swaps) makes on an FX rate.

A swap suits a **committed, ongoing exposure** — term debt you intend to hold, where you want the interest cost known and off the table.

## Caps: a ceiling, with the downside kept

An **interest rate cap** is an option. You pay an upfront **premium**, and in return the cap pays out whenever the reference rate resets above an agreed **strike**. Below the strike it does nothing and you simply pay the floating rate; above it, the payout offsets the excess, so your effective cost is capped.

- **Gives:** protection against rising rates _and_ the full benefit if rates fall — you stay on the floating rate below the strike.
- **Costs:** an upfront premium, whether or not it ever pays out.
- **Trade-off:** you pay for that flexibility, exactly as you would for an [FX option](https://gravam.com/blog/fx-hedging-instruments-forwards-options-swaps).

A cap suits a borrower who wants to sleep at night about a rate spike but doesn't want to lock away the benefit of falling rates — insurance, not a fixed price.

> A swap fixes your rate and takes the whole question off the table. A cap only removes the bad tail and leaves you the good one — which is exactly what you pay the premium for.

## Floors: the mirror

A **floor** is the cap turned around. It pays out when the reference rate falls _below_ a strike, protecting a party that _receives_ floating income — a floating-rate investor or lender — against rates dropping too far. Same option mechanics, opposite direction: a floor guards income the way a cap guards cost.

## Collars: funding the protection

A **collar** combines the two: you **buy a cap** and **sell a floor**. The premium you receive for selling the floor offsets — partly or entirely — the premium you pay for the cap, which is why a collar can be arranged at low or even zero upfront cost.

The catch is what you gave up to get there. Having sold the floor, you no longer keep the _full_ benefit if rates fall: below the floor strike you effectively pay the floor rate, because the floor you sold now pays out against you. So a collar fixes your cost into a **band** — a ceiling from the cap you bought, a lower bound from the floor you sold.

- **Gives:** capped cost with little or no upfront premium.
- **Costs:** you surrender the benefit of rates falling below the floor.
- **Trade-off:** the cheap middle ground between a swap and a naked cap — cheaper than the cap, more flexible than the swap, but no longer a free ride on falling rates.

## FRAs: locking one period

A **forward rate agreement** locks a rate for a **single future interest period**. You agree today the rate that will apply to a notional over one specified period ahead; at settlement, the difference between that agreed rate and the actual reference rate is paid one way or the other. Where a swap is effectively a strip of many periods fixed at once, an FRA fixes just one — useful for a specific dated exposure, like a known borrowing that falls in one future window.

## Swaptions: an option on the swap

A **swaption** is an option to _enter_ a swap at a future date on pre-agreed terms. It suits a conditional need — a borrowing that may or may not go ahead, where you want the right to lock a rate later without committing to the swap now. It's the same "right, not obligation" logic as a cap, applied to the swap itself.

## At a glance

|  | Swap | Cap | Collar | FRA |
| --- | --- | --- | --- | --- |
| **What** | Fix floating to fixed | Ceiling above a strike | Cap bought, floor sold | Fix one future period |
| **Upfront cost** | None | Premium | Low / zero | None |
| **Keeps downside benefit?** | No | Yes | Only above the floor | No |
| **Best for** | Committed term debt | Want a ceiling, keep upside | Cheap capped band | Single dated exposure |

## Choosing between them

There's no formula that picks the instrument — it comes down to your **view** on rates and your **appetite** for the downside:

- **Swap** — certainty, no premium, but no upside. You want the rate known and are content to give up the benefit of a fall.
- **Cap** — flexibility, at the cost of a premium. You want a ceiling but insist on keeping the benefit if rates drop.
- **Collar** — the cheap middle. Little or no premium, a capped cost, but you trade away the deep-downside benefit to fund it.

None of these is "best". The swap buyer who'd have saved on a cap and the cap buyer who paid a premium rates never justified both made defensible calls with the information they had. What isn't defensible is reaching for an instrument with **no underlying exposure** behind it — that's a rate bet, not a hedge, and exactly what [risk policy](https://gravam.com/blog/what-is-treasury-risk-management) exists to prevent.

## The accounting tail

Hedging these exposures has consequences on the books. A swap or cap carries a fair value that moves every period, and without the right treatment that volatility lands in your P&L even when the hedge is doing precisely its job — which is the whole reason [hedge accounting](https://gravam.com/blog/hedge-accounting-explained) exists. Decide the hedge and the accounting treatment together — including whether it will pass [effectiveness testing](https://gravam.com/blog/hedge-effectiveness-testing) — not months apart. (A quick sanity check with the [Hedge Effectiveness Checker](https://gravam.com/tools/hedge-effectiveness-checker) on expected fair-value changes costs minutes and can save a failed designation.)

## What usually goes wrong

- **Swapping debt you won't hold.** Fixing a rate on borrowing you refinance or repay early leaves a swap stranded against an exposure that's gone.
- **Treating a swap as free.** No premium doesn't mean no cost — you've locked away every benefit of a fall.
- **Buying caps and ignoring the premium.** The protection is real, but the premium is a genuine cost that has to be weighed against the risk it removes.
- **Selling a floor without pricing what you gave up.** A zero-cost collar isn't free — you sold the downside benefit to pay for the cap.
- **Hedging without an underlying exposure.** The cardinal error, same as in FX: an instrument that isn't offsetting a real rate exposure is a position, not a hedge.

Match the swap to committed debt, the cap to a borrower who wants a ceiling but keeps the downside, the collar to one who wants that ceiling cheaply, and the FRA to a single dated period — keep every instrument tied to a real exposure and sized to it, and interest rate hedging does its job: shaping a cost you don't control into one you can plan around, without turning treasury into a rate-trading desk.

***

_See also [interest rate risk in corporate treasury](https://gravam.com/blog/interest-rate-risk-in-corporate-treasury) and [what treasury risk management is](https://gravam.com/blog/what-is-treasury-risk-management)._

## Questions this article answers

**Q: What instruments hedge interest rate risk?**

The main ones are interest rate swaps, caps, floors, collars and forward rate agreements (FRAs). A swap exchanges floating-rate payments for fixed, locking the rate. A cap is an option that pays out when the reference rate rises above a strike, acting as insurance against rising rates for an upfront premium. A floor does the mirror for a floating-rate investor. A collar combines a bought cap with a sold floor to reduce or eliminate the premium. An FRA locks a rate for a single future interest period. Swaptions — options on a swap — sit alongside these for more conditional needs.

**Q: What is an interest rate swap?**

An interest rate swap is an agreement to exchange one stream of interest payments for another on a notional amount, most commonly floating for fixed. A borrower with floating-rate debt enters a payer swap — paying fixed and receiving floating — so the received floating leg offsets the floating interest on the underlying loan, leaving a net fixed cost. It locks the effective interest rate with no upfront premium, but it is an obligation: if rates fall, you are still paying the fixed rate and give up the benefit.

**Q: When would you use a cap instead of a swap?**

You use a cap when you want protection against rising rates but want to keep the benefit if rates fall — and you are willing to pay an upfront premium for that flexibility. A swap fixes your rate completely: certainty, no premium, but no upside if rates drop. A cap sets a ceiling while leaving you on the floating rate below it, so you still gain if rates fall. The choice comes down to your rate view and your appetite: a swap for certainty, a cap when you value keeping the downside.