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UN Membership

UN Photo 169039: Flags of many nations before San Francisco City Hall, 1945

Founding Member States

The United Nations was established by the Charter of the United Nations and Statute of the International Court of Justice.

The Charter was signed on 26 June 1945 by the representatives of 50 countries; Poland signed on 15 October 1945. There were 51 Founding Members in 1945. The founding members of the United Nations are the countries that were invited to participate in the 1945 San Francisco Conference at which the UN Charter and Statute of the ICJ was adopted. Participation was determined by virtue of having signed or adhered to the Declaration by United Nations (1942) or as approved at the Conference.

In accordance with Article 110, the Charter entered into force on 24 October 1945, after ratification by the five permanent members of the Security Council and a majority of the other countries. Twenty-two countries subsequently deposited their instruments of ratification. The table below reflects the pattern of ratification: first the five permanent members, then the other countries that ratified by 24 October, and then the remaining countries.

Since 1945, some of the Founding Members have changed their names, others have been dissolved and new states have succeeded them.

Original Member State Date of Signing Deposit of Ratification Current Name/Successor States
Republic of China 26 June 1945 28 Sept. 1945 People's Republic of China
France 26 June 1945 31 Aug. 1945  
Union of Soviet Socialist Republics 26 June 1945 24 Oct. 1945 Russian Federation
United Kingdom of Great Britain and Northern Ireland 26 June 1945 20 Oct. 1945  
United States of America 26 June 1945 8 Aug. 1945  
Argentina 26 June 1945 24 Sept. 1945  
Brazil 26 June 1945 21 Sept. 1945  
Byelorussian Soviet Socialist Republic 26 June 1945 24 Oct. 1945 Belarus
Chile 26 June 1945 11 Oct. 1945  
Cuba 26 June 1945 15 Oct. 1945  
Czechoslovakia 26 June 1945 19 Oct. 1945 Czechia and Slovakia
Denmark 26 June 1945 9 Oct. 1945  
Dominican Republic 26 June 1945 4 Sept. 1945  
Egypt 26 June 1945 22 Oct. 1945  
El Salvador 26 June 1945 26 Sept. 1945  
Haiti 26 June 1945 27 Sept. 1945  
Iran 26 June 1945 16 Oct. 1945  
Lebanon 26 June 1945 15 Oct. 1945  
Luxembourg 26 June 1945 17 Oct. 1945  
New Zealand 26 June 1945 19 Sept. 1945  
Nicaragua 26 June 1945 6 Sept. 1945  
Paraguay 26 June 1945 12 Oct. 1945  
Philippine Commonwealth 26 June 1945 11 Oct. 1945 Philippines
Poland 15 Oct. 1945 24 Oct. 1945  
Saudi Arabia 26 June 1945 18 Oct. 1945  
Syrian Arab Republic 26 June 1945 19 Oct. 1945  
Turkey 26 June 1945 28 Sept. 1945 Türkiye
Ukrainian Soviet Socialist Republic 26 June 1945 24 Oct. 1945 Ukraine
Yugoslavia 26 June 1945 19 Oct. 1945 Bosnia and Herzegovina, Croatia, Montenegro, North Macedonia, Serbia and Slovenia
Australia 26 June 1945 1 Nov. 1945  
Belgium 26 June 1945 27 Dec. 1945  
Bolivia 26 June 1945 14 Nov. 1945 Plurinational State of Bolivia
Canada 26 June 1945 9 Nov. 1945  
Colombia 26 June 1945 5 Nov. 1945  
Costa Rica 26 June 1945 2 Nov. 1945  
Ecuador 26 June 1945 21 Dec. 1945  
Ethiopia 26 June 1945 13 Nov. 1945  
Greece 26 June 1945 25 Oct. 1945  
Guatemala 26 June 1945 21 Nov. 1945  
Honduras 26 June 1945 17 Nov. 1945  
India 26 June 1945 30 Oct. 1945  
Iraq 26 June 1945 21 Dec. 1945  
Liberia 26 June 1945 2 Nov. 1945  
Mexico 26 June 1945 7 Nov. 1945  
Netherlands 26 June 1945 10 Dec. 1945 Netherlands (Kingdom of the)
Norway 26 June 1945 27 Nov. 1945  
Panama 26 June 1945 13 Nov. 1945  
Peru 26 June 1945 31 Oct. 1945  
Union of South Africa 26 June 1945 7 Nov. 1945 South Africa
Uruguay 26 June 1945 18 Dec. 1945  
Venezuela 26 June 1945 15 Nov. 1945 Bolivarian Republic of Venezuela