The euro is the official currency of 20 of the 27 European Union member states — a group called the eurozone or euro area — plus a handful of small non-EU countries and territories. Around 350 million people use it day to day, making it the second most-held reserve currency in the world after the US dollar.
The 20 EU countries in the eurozone
Austria, Belgium, Croatia, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Portugal, Slovakia, Slovenia and Spain. The original 11 adopted it for electronic payments in 1999 and as cash in 2002; the newest member is Croatia, which joined on 1 January 2023.
EU countries that do NOT use the euro
- Denmark has a formal opt-out negotiated in the Maastricht Treaty and pegs its krone to the euro instead.
- Sweden has no opt-out but has never joined the exchange-rate mechanism that is a precondition, effectively choosing to stay out after a 2003 referendum said no.
- Bulgaria, Czechia, Hungary, Poland and Romania are all legally committed to adopt the euro eventually but have not met or not pursued the criteria. Bulgaria is the closest and is targeting entry.
Non-EU countries and territories that use the euro
Four European microstates use the euro under formal monetary agreements with the EU and even mint their own euro coins: Andorra, Monaco, San Marino and Vatican City. Two more use it unilaterally, without an agreement: Kosovo and Montenegro, both of which adopted the euro's predecessor, the German mark, in the late 1990s and switched with it. Several French overseas territories (such as French Guiana, Réunion, Guadeloupe and Martinique) use the euro because they are legally part of France.
How a country joins
An EU member has to meet the four Maastricht convergence criteria — low inflation, sound public finances, a stable exchange rate for at least two years inside the ERM II mechanism, and low long-term interest rates — and then get unanimous approval from existing members. There is no way to use the euro as an official EU currency without first being in the EU, though nothing stops a non-member using it informally, as Kosovo and Montenegro do.
The eurozone cuts across the continent in a way national flags do not. Our Europe flags guide is a good companion for keeping the members straight.
Read the Europe flags guide →