ISO currency codes are those three-letter abbreviations (EUR, USD, GBP...) that identify each currency unambiguously around the world. Understanding how they work helps you read an exchange rate correctly and prepare for your trips with peace of mind.
What is an ISO currency code for?
The three-letter code comes from the international standard ISO 4217, managed by the International Organization for Standardization. Its logic is simple: the first two letters take the country code (according to another standard, ISO 3166), and the third generally corresponds to the initial of the currency's name. Thus USD stands for United States Dollar: "US" for the United States and "D" for Dollar. Likewise, GBP combines "GB" (Great Britain) with "P" for Pound, the pound sterling, and CHF designates the Swiss franc (CH for the Swiss Confederation, Confoederatio Helvetica, F for franc).
Why such precision? Because several countries use currencies that share the same common name. There is an American, Canadian, Australian, Singaporean dollar... Saying "100 dollars" means nothing on its own: USD, CAD and AUD have very different values. The ISO code removes all confusion, whether on an exchange board, a bank statement or a plane ticket.
The main codes to know
- EUR — the euro, currency of the eurozone (the exception that does not follow the country rule, "EU" designating Europe).
- USD — the US dollar, the benchmark currency of world trade.
- GBP — the British pound sterling, whose pair against the dollar (GBP/USD) is nicknamed cable by foreign-exchange traders.
- CHF — the Swiss franc, often regarded as a safe haven in times of uncertainty.
- JPY — the Japanese yen, whose prices are commonly displayed in whole yen, without cents.
- CAD, AUD, CNY (Chinese yuan), AED (Emirati dirham), MAD (Moroccan dirham), TRY (Turkish lira)...
In our list of more than 53 currencies, these codes are clearly displayed for each currency, which makes comparison easier before you book.
How to read an exchange rate
A rate is always written as a pair, for example EUR/USD. The first currency is called the "base" currency, the second the "quote" currency. The figure indicates how many units of the second currency you get for one unit of the first. Take a purely illustrative value (which is not today's rate): if EUR/USD were at 1.10, one euro would exchange for 1.10 dollars. Conversely, to find out how many euros a dollar costs, you calculate the inverse (1 divided by the displayed rate).
At a bureau de change, you will most often see two columns: a buy rate and a sell rate. These are counter rates, indicative and revised each day according to market movements. The gap between the two corresponds to the operator's margin. At Paris Change, exchange is carried out commission-free: the displayed rate is the rate applied, with no fees added on top.
A tip to avoid mistakes when travelling
Before you leave, memorise a simple mental benchmark, along the lines of "1 euro ≈ X units of the local currency." This helps you avoid overpaying on the spot, particularly at foreign ATMs or airport counters, which often apply unfavourable rates and fees. Booking your currency in advance, with the right ISO code and the right amount, remains the safest way to set off with peace of mind.
ISO codes and practical rules
The ISO code also helps you comply with regulations. When entering or leaving the European Union, any transport of cash equal to or greater than €10,000 (or the equivalent in another currency) must be the subject of a mandatory customs declaration. The threshold is assessed across all currencies combined: if you are carrying USD, GBP and CHF, it is the total converted value that counts. Knowing the code and value of each currency helps you estimate whether you are approaching this threshold.
Finally, some currencies are described as "exotic" or illiquid: exchanging them can be harder to arrange. The ISO-code reflex lets you quickly check the availability of a currency at an authorised bureau before your departure.
Why use an authorised bureau de change
Paris Change is a bureau de change authorised by the ACPR (the French Prudential Supervision and Resolution Authority, attached to the Banque de France). Our single shop is located at 4 Boulevard Saint-Michel, 75005 Paris, in the heart of the Latin Quarter, accessible via the Saint-Michel metro (line 4) as well as the RER B and C (Saint-Michel–Notre-Dame). We are open 7 days a week: Monday to Saturday from 9:00 am to 8:00 pm, and Sunday from 10:00 am to 7:30 pm. You can book your currency online and come and collect it in store.
Frequently asked questions
Why is the euro written EUR and not FRE or EUE?
Because the euro does not belong to a single country. The ISO 4217 standard chose "EU" for Europe, followed by "R" for euRo, in order to represent a currency shared by the entire eurozone.
Are the symbol (€, $, £) and the ISO code the same thing?
No. The symbol is a graphic shortcut in everyday use, but several currencies share the same symbol (the $ stands for the US dollar as well as the Canadian dollar). The ISO code, on the other hand, is unique and universal: it is the reliable reference for any exchange operation.
How can I find out whether a currency is available with you?
Simply check the list of currencies offered and find the ISO code matching your destination. You can then book the desired amount online and collect it in store.
Need to prepare your next trip? Check out our more than 53 currencies, verify today's rate and book online for commission-free collection at 4 Boulevard Saint-Michel.
