ORBIS

Alliance · Military

NATO

North Atlantic Treaty Organization

NATO is a military alliance of 32 countries in Europe and North America. Members promise that an armed attack on one counts as an attack on all. Twelve countries founded it in Washington on April 4, 1949, to deter the Soviet Union. Finland joined in 2023 and Sweden in 2024, after Russia's full-scale invasion of Ukraine.

Updated October 2026 · Members from NATO, spending from SIPRI

Flags of the member countries on tall poles around the NATO star sculpture at the entrance of NATO headquarters
Members' flags at NATO headquarters in Brussels. Photo: Adrian Cadiz, US Air Force, public domain.
Members
32
Sweden joined last, in 2024
Founded
1949
In Washington, by 12 countries
Headquarters
Brussels
Belgium
Military spending
$1.58tn
55% of the world's, 2025
Secretary General
Mark Rutte
Since October 2024

Which countries are in NATO?

Thirty-two countries: 30 in Europe, plus the United States and Canada. Twelve founded the alliance in 1949. After the Cold War, 14 formerly communist countries in central and eastern Europe joined between 1999 and 2020. Seven of them had been in the Soviet-led Warsaw Pact, three had been Soviet republics and four had been part of Yugoslavia. Finland and Sweden had stayed out of military alliances for decades. They applied together on May 18, 2022, almost three months after Russia's full-scale invasion of Ukraine. Turkey and Hungary held up both bids. Finland joined in April 2023 and Sweden in March 2024.

Map of Europe. The 30 European NATO members are blue. Ukraine, Georgia and Bosnia and Herzegovina, which want to join, are sand. Austria, Switzerland, Ireland, Serbia and the countries to the east are not members. United States and CanadaPlus the United States and Canada
  • Member
  • Wants to join
  • Not a member

How NATO grew

Countries that joined in each year, and the total after

  1. BelgiumCanadaDenmarkFranceIcelandItalyLuxembourgNetherlandsNorwayPortugalUnited KingdomUnited States194912 founders
  2. GreeceTurkey195214
  3. Germany195515
  4. Spain198216
  5. CzechiaHungaryPoland199919
  6. BulgariaEstoniaLatviaLithuaniaRomaniaSlovakiaSlovenia200426
  7. AlbaniaCroatia200928
  8. Montenegro201729
  9. North Macedonia202030
  10. Finland202331
  11. Sweden202432

All 32 members and the year each joined

  • Albania2009
  • Belgium1949
  • Bulgaria2004
  • Canada1949
  • Croatia2009
  • Czechia1999
  • Denmark1949
  • Estonia2004
  • Finland2023
  • France1949
  • Germany1955
  • Greece1952
  • Hungary1999
  • Iceland1949
  • Italy1949
  • Latvia2004
  • Lithuania2004
  • Luxembourg1949
  • Montenegro2017
  • Netherlands1949
  • North Macedonia2020
  • Norway1949
  • Poland1999
  • Portugal1949
  • Romania2004
  • Slovakia2004
  • Slovenia2004
  • Spain1982
  • Sweden2024
  • Turkey1952
  • United Kingdom1949
  • United States1949

Who wants to join NATO?

Ukraine, Georgia and Bosnia and Herzegovina. NATO calls them aspirant countries. At the Bucharest summit in April 2008, NATO's leaders said Ukraine and Georgia "will become members of NATO." They set no date. Ukraine applied on September 30, 2022. The 2024 Washington summit declaration called Ukraine's path "irreversible." The 2025 Hague and 2026 Ankara summit declarations said nothing about Ukraine's membership.

A new member needs a unanimous invitation from all 32 allies. Each member must then ratify the accession by its own national procedure. In February 2025, US Defense Secretary Hegseth said membership for Ukraine is not a realistic outcome of a peace deal. Slovakia's Prime Minister Fico has threatened to veto Ukraine's membership.

  • UkraineApplied in 2022

    It applied on September 30, 2022, the day Russia claimed to annex four Ukrainian regions. NATO has not invited it.

  • GeorgiaPromised in 2008

    Russian troops hold about a fifth of Georgia. NATO dropped its membership wording in July 2024 and left Georgia off the 2026 Ankara partner list.

  • Bosnia and HerzegovinaAction plan since 2018

    It was invited into NATO's Membership Action Plan in 2010 and began it in 2018. The leaders of its Serb-run region, Republika Srpska, oppose joining.

In the EU but not in NATO

  • Austria
  • Cyprus
  • Ireland
  • Malta

What is Article 5?

Article 5 of the North Atlantic Treaty says an armed attack on one member in Europe or North America counts as an attack on all. Each member then takes "such action as it deems necessary." Armed force is allowed but not required. The allies must first agree that an armed attack has occurred. Article 5 has been invoked once: on September 12, 2001, the day after the 9/11 attacks, and confirmed on October 2, 2001.

Article 4 is a weaker clause. Any member that feels its security is threatened can call the others to talks. Members have used Article 4 nine times, most recently by Poland and Estonia in September 2025 over Russian drones and jets entering their airspace.

The Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all.

Article 5, North Atlantic Treaty, 1949
Article 5 used
Once, September 12, 2001

After the 9/11 attacks. Seven NATO radar planes then patrolled US skies for seven months.

Article 4 talks
9 times
  1. 2003Turkey, before the Iraq war
  2. 2012Turkey, twice, after attacks from Syria
  3. 2014Poland, after Russia moved into Crimea
  4. 2015Turkey, after terrorist attacks
  5. 2020Turkey, after its soldiers were killed in Syria
  6. 2022Eight eastern members, the day Russia invaded Ukraine
  7. 2025Poland over Russian drones, then Estonia over Russian jets

How much do NATO members spend on defense?

NATO members spent $1.58 trillion on their militaries in 2025, by SIPRI's count, 55% of the world's $2.9 trillion. In 2014, members pledged to aim toward spending 2% of GDP on defense within a decade. At The Hague in June 2025, NATO's leaders set a goal of 5% of GDP a year by 2035. At least 3.5% goes to core defense. Up to 1.5% covers related spending such as protecting infrastructure and networks. Spain says 2.1% of GDP is enough for its commitments. Secretary General Rutte gave it a letter granting "flexibility", but the summit declaration names no exceptions. By SIPRI's count, only Poland and Latvia spent 3.5% or more of GDP in 2025. NATO's own estimates for 2026 put five members above that level: Lithuania, Estonia, Latvia, Poland and Greece.

Military spending as a share of GDP, 2025

Full ranking →
2%
Goal since 2014 3.5%
Core goal for 2035
  1. 4.5
  2. 3.6
  3. 3.4
  4. 3.3
  5. 3.3
  6. 3.1
  7. 3.1
  8. 3.0
  9. 2.6
  10. 2.5
  11. 2.4
  12. 2.3
  13. 2.3
  14. 2.2
  15. 2.1
  16. 2.0
  17. 2.0
  18. 2.0
  19. 1.9
  20. 1.9
  21. 1.8
  22. 1.7
  23. 1.6
  1. Poland
  2. Latvia
  3. Estonia
  4. Denmark
  5. Norway
  6. Lithuania
  7. United States
  8. Greece
  9. Finland
  10. Sweden
  11. United Kingdom
  12. Germany
  13. Romania
  14. Netherlands
  15. Spain
  16. Belgium
  17. France
  18. Hungary
  19. Italy
  20. Turkey
  21. Czechia
  22. Portugal
  23. Canada
  1. Poland4.5
  2. Latvia3.6
  3. Estonia3.4
  4. Denmark3.3
  5. Norway3.3
  6. Lithuania3.1
  7. United States3.1
  8. Greece3.0
  9. Finland2.6
  10. Sweden2.5
  11. United Kingdom2.4
  12. Germany2.3
  13. Romania2.3
  14. Netherlands2.2
  15. Spain2.1
  16. Belgium2.0
  17. France2.0
  18. Hungary2.0
  19. Italy1.9
  20. Turkey1.9
  21. Czechia1.8
  22. Portugal1.7
  23. Canada1.6
SIPRI estimates for 2025. NATO's own estimates use each country's fiscal year and its own definitions, and are often higher. Nine members are not in the ranking and not shown.

Is it in NATO?

Short answers for the countries people ask about most.

Is Ukraine in NATO?

No

Ukraine applied in September 2022. Members send it weapons, but NATO has not invited it and Article 5 does not cover it.

Is Sweden in NATO?

Yes

Sweden joined on March 7, 2024, the 32nd and newest member. Turkey and Hungary delayed its ratification for 659 days.

Is Finland in NATO?

Yes

Finland joined on April 4, 2023, the 31st member, 321 days after applying. It shares a long border with Russia.

Is Turkey in NATO?

Yes

Turkey joined in 1952. It has NATO's second-largest armed forces, with 355,200 active troops, and hosted the 2026 Ankara summit.

Is Switzerland in NATO?

No

Switzerland's neutrality was formally recognized at the Congress of Vienna in 1815. It has been a NATO partner since 1996.

Is Austria in NATO?

No

Austria's 1955 constitutional law makes it permanently neutral and bars military alliances. It has been a NATO partner since 1995.

Is Ireland in NATO?

No

Ireland keeps a policy of military neutrality. It has been a NATO partner since 1999 and an EU member since 1973.

Is Russia in NATO?

No

Russia was never a member. NATO set up a NATO-Russia Council in 2002 and suspended practical cooperation in April 2014.

Is Israel in NATO?

No

Israel has been a NATO partner since February 1995 through the Mediterranean Dialogue.

Is Japan in NATO?

No

Japan is one of NATO's four partners in the Indo-Pacific, alongside South Korea, Australia and New Zealand.

Other alliances

All alliances →
European Union 27 members · since 1993 Shared laws, one market and, for 21 members, the euro. Nine countries want to join. CSTO 6 members · since 1992 Russia and five former Soviet republics. Armenia froze its part in 2024. All alliances Who belongs to what Which alliances each country is in, and how big each one is. See every country →
7 days free cancel anytime
Get the app