When was the euro introduced?

Eleven European Union countries adopted the euro for banking and financial markets in 1999, while their national notes and coins stayed in use for another three years. On 1 January 2002 twelve countries, now including Greece, replaced currencies such as the German mark, French franc and Italian lira with euro cash in the biggest currency changeover in history. The European Central Bank in Frankfurt sets monetary policy for the euro area. Membership has since grown, with Croatia joining in 2023 and Bulgaria adopting the euro on 1 January 2026, bringing the total to 21 countries. The euro is the second most widely held reserve currency in the world after the US dollar.