How Exchange Rates Work and How to Avoid Hidden Currency Fees
The mid-market rate, the spread and dynamic currency conversion: what happens when you pay or send money in another currency.
Key takeaways
- The mid-market rate is the midpoint between buying and selling prices on the currency market; it is the fairest benchmark.
- Banks and exchange services earn money through a spread (a worse rate) and explicit fees.
- When paying abroad by card, choose the local currency and decline dynamic currency conversion.
- Compare the total amount received, not just the advertised fee.
An exchange rate is simply the price of one currency in terms of another. If EUR/USD is 1.10, one euro costs 1.10 US dollars. But when you actually convert money, whether at an airport kiosk, with your card or through a bank transfer, you rarely get the rate quoted in the news. Understanding why helps you avoid paying more than necessary.
How currency markets set exchange rates
Major currencies such as the US dollar (USD), euro (EUR), British pound (GBP), Japanese yen (JPY) and Swedish krona (SEK) trade on the global foreign exchange market, the largest financial market in the world. Banks, companies, investors and central banks buy and sell currencies around the clock, and prices move constantly with supply and demand.
Long-term and short-term drivers include:
- Interest rates: higher rates in a country tend to attract capital and support its currency.
- Inflation: persistently higher inflation tends to weaken a currency over time.
- Economic growth and trade: strong exports create demand for a country's currency.
- Risk sentiment: in times of uncertainty, investors often move into currencies seen as safe havens.
- Central bank actions and expectations: markets react to what central banks do and to what they are expected to do.
Some currencies float freely, while others are pegged to another currency or managed within a range by their central bank.
The mid-market rate and the spread
At any moment, the market has a bid (the price buyers pay) and an ask (the price sellers want). The mid-market rate lies exactly between them. It is the rate you see on financial news sites and search engines.
Consumer providers usually convert at a rate that is worse than the mid-market rate and keep the difference. This markup, called the spread, is a cost even when the provider advertises "no fees".
Example (illustrative rates)
You exchange €1,000 into dollars. At a mid-market rate of 1.10 you would receive $1,100. A provider that applies a 3% markup gives you a rate of about 1.067, so you receive about $1,067. The $33 difference is the real cost of the conversion, on top of any explicit fee.
Where currency costs hide
| Situation | Typical cost |
|---|---|
| Airport and tourist exchange counters | Wide spreads, sometimes plus a commission |
| Card payments abroad | Foreign transaction fee (often around 3%) on many cards, plus the network rate |
| Cash withdrawals abroad | Your bank's fee, the ATM operator's fee and possibly a conversion markup |
| International bank transfers | Transfer fee, intermediary bank fees and an exchange rate markup |
| Dynamic currency conversion | Often a markup of several percent on the exchange rate |
Dynamic currency conversion: always say no
When you pay by card abroad, a terminal or ATM may offer to charge you in your home currency. This is called dynamic currency conversion (DCC). It looks convenient because you see the amount in familiar money, but the merchant's provider sets the exchange rate, and it is usually much worse than the rate your card network would use.
The rule is simple: always choose to pay in the local currency. Your card issuer then converts the amount at the network rate, minus any foreign transaction fee your card charges.
How to convert money at a fair price
- Check the mid-market rate before you convert so you can judge the offer.
- Use a card without foreign transaction fees for spending abroad. Many travel credit cards and some debit cards waive them.
- Compare the total amount the recipient gets when sending money abroad; specialist transfer services are often cheaper than traditional banks.
- Avoid exchanging cash at airports and hotels. If you need cash, withdrawing a larger amount once is usually cheaper than several small withdrawals.
- Decline dynamic currency conversion every time.
Exchange rate risk for savers and investors
If you hold savings or investments in a foreign currency, your returns depend on the exchange rate as well as on interest or price changes. A 4% interest rate on a foreign-currency account can turn into a loss if that currency falls by more than 4% against your home currency. Currency movements also affect international ETFs. Some funds hedge currency risk, at a cost; many do not.
Explore more in our exchange rate guides.
