The Baltic states (Estonian: Balti riigid, Latvian: Baltijas valstis, Lithuanian: Baltijos valstybės), Baltic Nations or Baltic countries are three countries in Northern Europe, all members of the European Union: Estonia, Latvia and Lithuania. Between 1918 and 1920 in the aftermath of World War I, following centuries of foreign domination, the Baltic countries were reestablished as independent nations. Initially after 1918, Finland was considered to be one of the Baltic States since it too emerged with the other three countries under similar circumstances. Today however, Finland is more often grouped within Scandinavia.

Estonians and the nearly linguistically extinct Livonian people in Latvia are descended from the Baltic Finns, sharing closely related languages and a common cultural ancestry. The Latvians and Lithuanians, linguistically and culturally related to each other, are descended from the Balts, an Indo-European people and culture. The peoples comprising the Baltic states have together inhabited the eastern Baltic coast for millennia, although not always peacefully in ancient times, over which period their populations: Estonian, Latvian, Lithuanian, have remained remarkably stable within the approximate territorial boundaries of the current Baltic states. While separate peoples with their own customs and traditions, historical factors have introduced cultural commonalities across and differences within them.

The term "Baltic republics" can sometimes refer in historic context to the Baltic republics of the Soviet Union. At the same time the three countries were considered under Soviet occupation by the United States, the United Kingdom and some other Western nations. The Baltic States' struggle for independence is believed to have contributed greatly to the collapse of the Soviet Union. The sovereignties of the countries were restored in 1991 and the last Russian troops withdrew from the Baltic States in August 1994.

Estonia, Latvia and Lithuania have been members of the European Union and NATO since 2004. Today the three countries are liberal democracies and their market economies have in recent years undergone rapid expansion.