Euro convergence criteria

The euro convergence criteria (also known as the Maastricht criteria) are the criteria European Union member states are required to meet to enter the third stage of the Economic and Monetary Union (EMU) and adopt the euro as their currency. The four main criteria, which actually comprise five criteria as the "fiscal criterion" consists of both a "debt criterion" and a "deficit criterion", are based on Article 140 (ex article 121.1) of the Treaty on the Functioning of the European Union.

Source: Wikipedia — Euro convergence criteria (CC BY-SA 4.0)