NATO Member Countries — Complete List (2024)

The North Atlantic Treaty Organization (NATO) is a military alliance founded in 1949 with 12 original member states. As of 2024, NATO has 32 member countries following Sweden's accession in March 2024 and Finland's in 2023. NATO's core principle is collective defense — an attack on one member is considered an attack on all. Article 5 of the NATO treaty has only been invoked once, following the September 11, 2001 terrorist attacks on the United States. NATO members span North America and Europe, from Canada and the United States to Turkey and the Baltic states.

NATO members are expected to spend at least 2% of their GDP on defense — a target first agreed in 2006 but met by few members until Russia's invasion of Ukraine in 2022 dramatically changed the security calculus across Europe. Countries like Poland, Estonia, Latvia, and Lithuania now exceed 3% of GDP in defense spending, while Germany has significantly increased its military budget after decades of restraint. The debate over burden-sharing, particularly with the United States bearing disproportionate costs, has been a recurring source of tension within the alliance.

NATO has expanded significantly since the Cold War, growing from 16 members in 1991 to 32 today. This eastern enlargement has been a major point of contention with Russia, which views NATO expansion toward its borders as a threat. The alliance has repeatedly stated that membership is open to any European country that meets democratic and military standards. Ukraine and Georgia were promised eventual membership at the 2008 Bucharest Summit, though no timeline was set — a question that remains central to European security discussions.