Currency Swaps Explained: Mechanics & Worked Example

Currency swaps are explicitly named on ACCA Advanced Financial Management (AFM), under the use of financial derivatives to hedge against forex risk. They're the cross-border cousin of the interest rate swap — the underlying logic (two parties exchanging obligations to get better terms than either could arrange alone) is the same, but a currency swap also exchanges principal in two different currencies, which is what makes it useful for hedging long-term foreign exchange exposure.

What is a currency swap?

A currency swap is an agreement between two parties to exchange the principal amount of a loan, and the interest due on it, in one currency for the principal and interest on an equivalent loan in a different currency. Unlike an interest rate swap, where only interest cash flows are exchanged, a currency swap involves an actual exchange of principal at the start of the arrangement (usually at the current spot rate) and a reversal of that same exchange at maturity — typically at the original rate agreed at inception, not the market rate prevailing at that future date.

Why use a swap instead of just borrowing directly abroad?

A company that needs long-term financing in a foreign currency has two broad choices: borrow directly in that currency, or borrow in its home currency (where it may have better access to credit or lower rates) and swap into the foreign currency it actually needs. The swap route can be cheaper when the company's counterparty has comparative advantage in the other market — exactly the same comparative-advantage logic used in interest rate swaps, just applied across two different currencies rather than two different rate bases.

A worked example

Suppose a US company needs €500m of five-year financing for a European acquisition. Borrowing directly in the eurozone would cost it ESTR + 1.5%, reflecting its weaker credit standing outside its home market. Borrowing in US dollars, where it has strong credit, costs only 3.6%. A European counterparty has the opposite problem — strong credit at home in euros, but a costly rate if it tried to borrow dollars directly.

Rather than each company borrowing directly in the currency it actually needs (at an unfavourable rate), each borrows in its own strongest market and the two swap: the US company borrows dollars at 3.6%, the European company borrows euros at its own best rate, and they exchange the principal and ongoing interest obligations. After the swap, the US company can end up paying an effective rate of around ESTR + 0.9% for its euro financing — a full 0.6 percentage points cheaper than the ESTR + 1.5% it would have paid borrowing euros directly.

At inception, the €500m principal is exchanged for its dollar equivalent at the prevailing spot rate — say $446.4m. At maturity in five years, that same exchange is reversed at the same rate agreed at the start, not whatever the spot rate happens to be in five years' time. That's the specific mechanism that makes the swap a genuine long-term FX hedge: the company knows exactly how many dollars it will need to hand back in five years to recover its euros, regardless of how the exchange rate moves in the meantime.

What this hedges, and what it doesn't

A currency swap hedges the principal-repayment exchange rate risk over the life of the arrangement — the single biggest source of uncertainty in long-term foreign-currency borrowing. It doesn't remove all currency exposure a business might have (transaction exposure on day-to-day trading cash flows, for example, is typically hedged separately with shorter-dated instruments like forward contracts or currency options). Currency swaps are specifically a long-term financing and hedging tool, used when a company has an ongoing, multi-year foreign-currency funding need rather than a series of short, one-off transactions.

Counterparty risk in a currency swap

As with an interest rate swap, entering a currency swap doesn't remove either party's underlying obligation to its own original lender — it sits alongside those loans as a separate contract exchanging cash flows between the two counterparties, usually arranged and guaranteed by a bank. If one party defaults partway through the arrangement, the other is still legally required to service its own original loan, even though the economic benefit of the swap disappears. This counterparty risk is one reason banks typically sit in the middle of these arrangements rather than leaving two corporates to deal with each other directly, and it's a point AFM examiners occasionally test alongside the mechanical calculation of the swap's benefit.

FAQs

Is principal actually exchanged in a currency swap, unlike an interest rate swap?
Yes — this is the key structural difference. An interest rate swap only exchanges interest cash flows on a notional amount that's never actually paid over; a currency swap genuinely exchanges the principal at the start and reverses that exchange at maturity, because the whole point is to give each party access to real funds in the currency it needs.

Why is the principal reversed at the original rate rather than the future spot rate?
Because reversing at the original agreed rate is exactly what removes exchange rate uncertainty from the arrangement — if the reversal used the future spot rate instead, the company would still be exposed to FX movements on the principal, defeating the purpose of the hedge.

Which ACCA paper examines currency swaps?
ACCA AFM, under the use of financial derivatives to hedge against forex risk, alongside forward contracts and currency options as the other main forex-hedging tools on the syllabus.