Why does the world still have so many currencies?
A world that will not give up its 150-odd wallets.
One currency would end the need to exchange. Yet more than 150 currencies remain. Countries that share, countries that borrow, countries that hold on — the reasons, set side by side.
In 30 seconds
- The international currency standard, ISO 4217, lists 155 currencies once funds, precious metals and units of account are set aside (edition of 17 September 2026).
- Some countries share a currency. The euro is used by 21 countries, the West African CFA franc by 8 and the Central African CFA franc by 6. Some countries use the US dollar as their own.
- A major reason to keep a currency is that when growth and inflation differ between countries, an interest rate and exchange rate of one’s own can soften the shock (the idea of an optimum currency area).
The wallets number 150-odd.
Counting the international standard’s list, there are 155 currencies in use today.
Currencies in current use in the international currency standard
Our own count, excluding funds, gold and silver, and units of account. The list has 178 codes in all.
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How we counted
The ISO 4217 list (edition of 17 September 2026) contains 178 currency codes. Excluding index-linked funds, precious metals such as gold and silver, and the units of account used by international bodies leaves 155 currencies used by countries and territories.[1]
There are fewer currencies than countries because several countries sometimes share one.
Countries that share one wallet.
There are several arrangements in which a group of countries uses a single currency.
Countries that use the euro
Bulgaria joined on 1 January 2026.
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The euro
Bulgaria adopted the euro on 1 January 2026, becoming the 21st country in the euro area.[2]
Africa and the Caribbean
The West African CFA franc is used in eight countries — Benin, Burkina Faso, Côte d’Ivoire, Guinea-Bissau, Mali, Niger, Senegal and Togo — and the Central African CFA franc in six: Cameroon, the Central African Republic, Chad, the Republic of the Congo, Equatorial Guinea and Gabon. The Eastern Caribbean dollar is used in eight countries and territories, including Antigua and Barbuda, Dominica and Grenada.[1]
Countries that borrow someone else’s wallet.
Some countries have no currency of their own and use another country’s currency as it is.
Countries and territories where the US dollar is used, in the international standard’s list
Includes the United States and its overseas territories.
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Countries that use the dollar
In the international standard’s list, the US dollar is used in Ecuador, El Salvador, Panama, Palau, the Marshall Islands, the Federated States of Micronesia and Timor-Leste, among others.[1]
Using the dollar removes the cost of exchanging with the United States. In return, interest rates are set by conditions in the United States, and cannot be moved by the country alone.
The main reason to hold on.
If growth and prices move differently between countries, an interest rate and exchange rate of one’s own make shocks easier to absorb.
The year the economist Robert Mundell set out the idea of an “optimum currency area”
The less easily workers move between countries, the more separate currencies matter.
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Optimum currency areas
In the idea Mundell set out in 1961, countries with different characteristics absorb economic shocks more easily if each has its own monetary and exchange rate policy — particularly where workers do not move easily across borders.[3]
The price of sharing
Sharing a currency removes the cost of exchange. In return, the interest rate becomes one for the whole group. In the euro area, it is set by the European Central Bank.[2]
A scale for reading what comes next.
A scale to keep in mind as the map of currencies shifts.
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Countries joining in
Whether new countries join a shared currency such as the euro.[2]
Borrowing and returning
Whether countries using another country’s currency seek one of their own, or the reverse.[1]
The standard’s list
The international standard’s list is rewritten each time a currency is born or retired.[1]
This is not investment advice
This edition explains how currencies work. It does not recommend buying or selling any currency.
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NEXT QUESTIONThe deepest tap in money.NEXT QUESTIONThe largest market in the world has no building.See the Field Notes shelf →What this edition cannot tell you
- An official way of counting “the number of currencies” in the world. This edition counts the international standard’s list itself.
- The detailed rules of each currency-sharing arrangement, such as how exchange rates are fixed.