What it means
Foreign exchange, often shortened to FX, covers both the act of swapping currencies and the market where prices for those swaps are set. There is no single exchange building; banks, brokers, companies and funds trade with each other electronically, around the clock, five days a week.
Prices are quoted as pairs, such as 1.10 dollars per euro, and they move whenever the balance of buyers and sellers shifts. For most businesses the issue is not speculation but certainty.
If you agree a price today in a currency you do not hold, your real cost or revenue stays unknown until the money actually changes hands. That gap between agreeing and settling is where foreign exchange risk lives.
Rates are quoted two ways round, and mixing them up is the classic error. A quote of 0.90 euros per dollar and a quote of 1.11 dollars per euro describe exactly the same relationship, but dividing when you should have multiplied doubles the error rather than cancelling it.
Always sanity-check the answer against common sense before it reaches a customer quote. Most day-to-day conversion happens at the spot rate, meaning settlement within a couple of working days.
Banks earn a spread, the gap between the rate at which they buy and the rate at which they sell, so the rate on your statement is always slightly worse than the mid-market rate quoted online. On large transfers that spread is worth negotiating rather than accepting.
Companies manage the underlying risk by matching currency income against currency costs, holding foreign currency accounts, or buying forward contracts that fix a rate now for a future date. None of these makes the risk disappear; each simply trades an uncertain outcome for a known one.
Most finance teams prefer predictability to the chance of a lucky move.
In practice
Real-world examples.
Example
A US furniture retailer orders from an Italian supplier and is invoiced in euros with 90-day payment terms. Because the rate moves in the meantime, the finance team quotes retail prices using a conservative internal rate rather than the spot rate on the order date.
Example
A software company headquartered in Boston bills Canadian customers in Canadian dollars to make buying easy. Its reported revenue therefore moves with the exchange rate even when the number of subscriptions is flat, so the board reviews growth on a constant-currency basis.
Example
A mining group earns dollars from commodity sales but pays wages and diesel in Australian dollars. A stronger Australian dollar raises its cost base without changing its revenue, so treasury holds part of its cash in the local currency as a natural offset.
Think of it
“Foreign exchange is trading currencies-converting one currency to another.
Formula
Calculation
Cost in home currency = amount in foreign currency / units of foreign currency per home currency unit
A US furniture retailer receives an invoice for 540,000 euros, payable in three months. At the time of ordering the rate is 0.90 euros per dollar, so the expected cost is 540,000 / 0.90 = $600,000. By the settlement date the dollar has weakened to 0.80 euros per dollar, so the actual cost is 540,000 / 0.80 = $675,000. The unhedged move has added $675,000 - $600,000 = $75,000 to the cost of the shipment, which on a planned gross margin of $150,000 wipes out half the profit on the order.Case study
Seen in the real world.
Harborline Coffee Importers is an invented company used to illustrate the point. It bought green coffee in dollars, sold roasted coffee in three European markets in euros, and for years treated exchange rates as background noise handled by whoever was in the office that week.
In this fictional example a 9% move against it over one season turned a budgeted 11% operating margin into 4%, even though every sales and volume target had been met. The board could not tell how much of the shortfall was trading performance and how much was currency, because the two were mixed together in the same reported figures.
The response was to fix an internal budget rate at the start of each season, report trading results at that rate, and show currency gains and losses as a separate line. Nothing about the market changed, but for the first time management could see which part of the result they actually controlled.
Watch out
Common mistakes.
- Using the mid-market rate seen on a search engine to work out what a transfer will cost. That rate is the midpoint between buying and selling prices; the rate a business is actually offered includes a spread and often a fee on top.
- Inverting a quote by accident. Multiplying where you should divide produces an answer that is wrong by the square of the rate, which on a large invoice is an expensive slip that spreadsheets will not catch for you.
- Believing that a business with no overseas customers has no currency exposure. If your suppliers, cloud hosting or raw materials are priced abroad, the exposure sits in your cost base rather than your revenue.
Questions
People also ask.
What is the difference between the spot rate and the forward rate?
The spot rate is for near-immediate settlement, while the forward rate fixes a price today for an exchange on a specified future date.
Should a small business hedge its currency exposure?
If a single transaction is large enough that an adverse move would materially damage the year, fixing the rate is usually worth the modest cost; for small, frequent amounts the administration rarely pays for itself.
Why do reported revenues change when nothing was sold differently?
Overseas results are translated back into the reporting currency at prevailing rates, so a stronger home currency shrinks foreign revenue on paper without any change in underlying trading.
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