| Country / Date of Membership | Country / Date of Membership |
| Afghanistan, Jul 14, 1955 | Liberia, Mar 28, 1962 |
| Albania, Oct 15, 1991 | Libya, Sep 17, 1958 |
| Algeria, Sep 26, 1963 | Lithuania, Jul 6, 1992 |
| Angola, Sep 19, 1989 | Luxembourg, Dec 27, 1945 |
| Antigua and Barbuda, Sep 22, 1983 | Madagascar, Sep 25, 1963 |
| Argentina, Sep 20, 1956 | Malawi, Jul 19, 1965 |
| Armenia, Sep 16, 1992 | Malaysia, Mar 7, 1958 |
| Australia, Aug 5, 1947 | Maldives, Jan 13, 1978 |
| Austria, Aug 27, 1948 | Mali, Sep 27, 1963 |
| Azerbaijan, Sep 18, 1992 | Malta, Sep 26, 1983 |
| Bahamas, The, Aug 21, 1973 | Marshall Islands, May 21, 1992 |
| Bahrain, Sep 15, 1972 | Mauritania, Sep 10, 1963 |
| Bangladesh, Aug 17, 1972 | Mauritius, Sep 23, 1968 |
| Barbados, Sep 12, 1974 | Mexico, Dec 31, 1945 |
| Belarus, Jul 10, 1992 | Micronesia, Federated States of, Jun 24, 1993 |
| Belgium, Dec 27, 1945 | Moldova, Aug 12, 1992 |
| Belize, Mar 19, 1982 | Mongolia, Feb 14, 1991 |
| Benin, Jul 10, 1963 | Montenegro, Jan 18, 2007 |
| Bhutan, Sep 28, 1981 | Morocco, Apr 25, 1958 |
| Bolivia, Dec 27, 1945 | Mozambique, Sep 24, 1984 |
| Bosnia and Herzegovina, Feb 25, 1993 | Myanmar, Jan 3, 1952 |
| Botswana, Jul 24, 1968 | Namibia, Sep 25, 1990 |
| Brazil, Jan 14, 1946 | Nauru, Apr 12, 2016 |
| Brunei Darussalam, Oct 10, 1995 | Nepal, Sep 6, 1961 |
| Bulgaria, Sep 25, 1990 | Netherlands, Dec 27, 1945 |
| Burkina Faso, May 2, 1963 | New Zealand, Aug 31, 1961 |
| Burundi, Sep 28, 1963 | Nicaragua, Mar 14, 1946 |
| Cabo Verde, Nov 20, 1978 | Niger, Apr 24, 1963 |
| Cambodia, Jul 22, 1970 | Nigeria, Mar 30, 1961 |
| Cameroon, Jul 10, 1963 | North Macedonia, Feb 25, 1993 |
| Canada, Dec 27, 1945 | Norway, Dec 27, 1945 |
| Central African Republic, Jul 10, 1963 | Oman, Dec 23, 1971 |
| Chad, Jul 10, 1963 | Pakistan, Jul 11, 1950 |
| Chile, Dec 31, 1945 | Palau, Dec 16, 1997 |
| China, Dec 27, 1945 | Panama, Mar 14, 1946 |
| Colombia, Dec 24, 1946 | Papua New Guinea, Oct 9, 1975 |
| Comoros, Oct 28, 1976 | Paraguay, Dec 28, 1945 |
| Congo, Democratic Republic of, Sep 28, 1963 | Peru, Dec 31, 1945 |
| Congo, Republic of, Jul 10, 1963 | Philippines, Dec 27, 1945 |
| Costa Rica, Jan 8, 1946 | Poland, Jun 27, 1986 |
| Cote d'Ivoire, Mar 11, 1963 | Portugal, Mar 29, 1961 |
| Croatia, Feb 25, 1993 | Qatar, Sep 25, 1972 |
| Cyprus, Dec 21, 1961 | Romania, Dec 15, 1972 |
| Czechia, Jan 1, 1993 | Russian Federation, Jun 16, 1992 |
| Denmark, Mar 30, 1946 | Rwanda, Sep 30, 1963 |
| Djibouti, Oct 1, 1980 | Samoa, Jun 28, 1974 |
| Dominica, Sep 29, 1980 | San Marino, Sep 21, 2000 |
| Dominican Republic, Sep 18, 1961 | Sao Tome and Principe, Sep 30, 1977 |
| Ecuador, Dec 28, 1945 | Saudi Arabia, Aug 26, 1957 |
| Egypt, Arab Republic of, Dec 27, 1945 | Senegal, Aug 31, 1962 |
| El Salvador, Mar 14, 1946 | Serbia, Feb 25, 1993 |
| Equatorial Guinea, Jul 1, 1970 | Seychelles, Sep 29, 1980 |
| Eritrea, Jul 6, 1994 | Sierra Leone, Sep 10, 1962 |
| Estonia, Jun 23, 1992 | Singapore, Aug 3, 1966 |
| Eswatini, Sep 22, 1969 | Slovak Republic, Jan 1, 1993 |
| Ethiopia, Dec 27, 1945 | Slovenia, Feb 25, 1993 |
| Fiji, May 28, 1971 | Solomon Islands, Sep 22, 1978 |
| Finland, Jan 14, 1948 | Somalia, Federal Republic of, Aug 31, 1962 |
| France, Dec 27, 1945 | South Africa, Dec 27, 1945 |
| Gabon, Sep 10, 1963 | South Sudan, Apr 18, 2012 |
| Gambia, The, Oct 18, 1967 | Spain, Sep 15, 1958 |
| Georgia, Aug 7, 1992 | Sri Lanka, Aug 29, 1950 |
| Germany, Aug 14, 1952 | St. Kitts and Nevis, Aug 15, 1984 |
| Ghana, Sep 20, 1957 | St. Lucia, Jun 27, 1980 |
| Greece, Dec 27, 1945 | St. Vincent and the Grenadines, Aug 31, 1982 |
| Grenada, Aug 27, 1975 | Sudan, Sep 5, 1957 |
| Guatemala, Dec 28, 1945 | Suriname, Jun 27, 1978 |
| Guinea, Sep 28, 1963 | Sweden, Aug 31, 1951 |
| Guinea-Bissau, Mar 24, 1977 | Switzerland, May 29, 1992 |
| Guyana, Sep 26, 1966 | Syrian Arab Republic, Apr 10, 1947 |
| Haiti, Sep 8, 1953 | Tajikistan, Jun 4, 1993 |
| Honduras, Dec 27, 1945 | Tanzania, Sep 10, 1962 |
| Hungary, Jul 7, 1982 | Thailand, May 3, 1949 |
| Iceland, Dec 27, 1945 | Timor-Leste, Jul 23, 2002 |
| India, Dec 27, 1945 | Togo, Aug 1, 1962 |
| Indonesia, Apr 13, 1967 | Tonga, Sep 13, 1985 |
| Iran, Islamic Republic of, Dec 29, 1945 | Trinidad and Tobago, Sep 16, 1963 |
| Iraq, Dec 27, 1945 | Tunisia, Apr 14, 1958 |
| Ireland, Aug 8, 1957 | Türkiye, Mar 11, 1947 |
| Israel, Jul 12, 1954 | Turkmenistan, Sep 22, 1992 |
| Italy, Mar 27, 1947 | Tuvalu, Jun 24, 2010 |
| Jamaica, Feb 21, 1963 | Uganda, Sep 27, 1963 |
| Japan, Aug 13, 1952 | Ukraine, Sep 3, 1992 |
| Jordan, Aug 29, 1952 | United Arab Emirates, Sep 22, 1972 |
| Kazakhstan, Jul 23, 1992 | United Kingdom, Dec 27, 1945 |
| Kenya, Feb 3, 1964 | United States, Dec 27, 1945 |
| Kiribati, Sep 29, 1986 | Uruguay, Mar 11, 1946 |
| Korea, Republic of, Aug 26, 1955 | Uzbekistan, Sep 21, 1992 |
| Kosovo, Jun 29, 2009 | Vanuatu, Sep 28, 1981 |
| Kuwait, Sep 13, 1962 | Venezuela, Republica Bolivariana de, Dec 30, 1946 |
| Kyrgyz Republic, Sep 18, 1992 | Viet Nam, Sep 21, 1956 |
| Lao People's Democratic Republic, Jul 5, 1961 | Yemen, Republic of, Oct 3, 1969 |
| Latvia, Aug 11, 1992 | Zambia, Sep 23, 1965 |
| Lebanon, Apr 14, 1947 | Zimbabwe, Sep 29, 1980 |
| Lesotho, Jul 25, 1968 | |