A member state is a state that is a member of an international organization or of a federation or confederation.
Since the World Trade Organization (WTO) and the International Monetary Fund (IMF) include some members that are not sovereign states, neither organization ever speaks of "member states". The WTO has simply "members" (see WTO members), and the IMF refers to its members as "member countries".[1]
The oldest global member state based organization is the International Telecommunication Union, which joined the United Nations System as a Specialized Agency of the T1088 after the creation of the UN.
| Count | Region | Note | ||
|---|---|---|---|---|
| Member states of the Council of Europe | 47 | Europe | ||
| Member state of the European Union | 27 | Europe | ||
| Member states of the European Economic Area | 30 | Europe | EU + Iceland, Liechtenstein, Norway | |
| Member states of the European Environment Agency | 32 | Europe | EU + Iceland, Liechtenstein, Norway, Switzerland, Turkey [3] | |
| Member states of the European Aviation Safety Agency | 31 | Europe | EU + Iceland, Liechtenstein, Norway, Switzerland | |
| Member states of the European Union Customs Union | 31 | Europe | EU + Turkey, San Marino, Andorra, Monaco | |
| Member states of the Eurozone | 19 | Europe | ||
| Member states of the European Free Trade Association | 4 | Europe | ||
| Member states of the Organization of the Black Sea Economic Cooperation | Europe | |||
| Central European Free Trade Agreement | Europe | |||
| Member states of the European Southern Observatory | 15 | Europe | ||
| Nordic Council#Members | 5 | Europe | ||
| Council of the Baltic Sea States#Member states | Europe | |||
| Western European and Others Group#WEOG Member States | Europe | |||
| Eastern European Group#Members | Europe | |||
| European Space Agency | 22 | Europe | 1 Associate Canada | |
| Member states of the Organization of American States | 35 | America | +75 Permanent Observers[4] | |
| Member states of the Union of South American Nations | 12 | America | ||
| Member states of Mercosur | 5 | America | ||
| Member states of the Bolivarian Alliance for the Americas | 8 | America | ||
| Member states of the Caribbean Community | 15 | America | ||
| Association of Caribbean States#Member states | 25 | America | ||
| Caribbean Meteorological Organisation | America | |||
| Inter-American Development Bank#Member states | 48 | America | ||
| Member states of the African Union | 55 | Africa | 9 observer states + 1 suspended | |
| Southern African Development Community | 14 | Africa | ||
| Member states of the Association of Southeast Asian Nations | 10 | Asia | ||
| Member states of the Cooperation Council for the Arab States of the Gulf | 6 | Asia | ||
| Member states of Shanghai Cooperation Organisation | 6 | Asia | +5 observers | |
| United Nations Economic and Social Commission for Western Asia#Member states | 14 | Asia | ||
| Economic Cooperation Organization#Member states | 10 | Asia | ||
| Arctic Council#Member states | 8 | Arctic | 13 observers |
In history: