List of treaties by number of parties
This article contains a list of treaties by number of parties to the treaty. A "party" to a treaty is a state or other entity that ratifies, accedes to, approves, or succeeds to the treaty.
General principles of ratification
In general, multilateral treaties are open to ratification by any state. Some treaties may also be ratified by supranational bodies, such as the European Union, and by other international organizations.In practice, the depositary of a treaty will usually only recognise ratifications of the treaty that are performed by a state that is recognised as a state at international law. A state can be formally recognised as such by becoming a member of the United Nations; there are currently member states of the United Nations. The only non-UN states that undoubtedly meet the standard of statehood are the Cook Islands and Niue, who have had their "full treaty-making capacity" recognised by the United Nations Secretariat. Vatican City is also widely recognised as being able to legitimately ratify treaties, and has been granted non-member observer state status by the UN General Assembly. Following the UNGA passing a resolution granting non-member observer state status to the State of Palestine, the UNSG has begun to recognize its right to ratify treaties. Ratifications performed by other states with more limited recognition—such as the Republic of China ; Kosovo; Northern Cyprus; Somaliland; the Sahrawi Arab Democratic Republic ; South Ossetia; Abkhazia; Transnistria; and Nagorno-Karabakh—have usually not been recognised by treaty depositaries as states that can ratify treaties, although there are some exceptions to this general rule.
If a state party to a treaty denounces the treaty, the state is no longer a party to the treaty, although in some cases certain parts of the treaty may continue to apply.
Ratifications by defunct states
States change over time, and often a state that ratified a treaty will cease to exist. International law deals with this issue in two ways. First, it is possible for a state to be declared the successor state to the defunct state. In this situation, any ratifications performed by the defunct state are transferred to and attributed to the successor state. Examples of successor states are the Russian Federation, Serbia, Belarus, Ukraine, and Tanzania. It is possible for a single state to be the successor state of multiple states, as with Yemen being the successor state of both North Yemen and South Yemen.Second, some states have no legal successor state but cease to exist; in such cases, the ratifications performed by the state are disregarded. In some cases, such states are subsumed into an existing state, as when East Germany became part of the Federal Republic of Germany, and when Zanzibar became part of Tanzania. In other cases, the defunct state is divided into two or more states, with none of the states being designated as the formal successor state. Examples of the latter situation include SFR Yugoslavia and Czechoslovakia. In this situation, the new states usually declare which treaties the defunct state ratified continue to have force for the new state. Such a declaration is regarded as a "ratification" by the new state.
For purposes of the numbers in this list, only ratifications, accessions, or successions of currently existing states are considered. No regard is given to ratifications by defunct states that have no current successor state.
Maximum limits to ratification numbers?
Due to these limitations, in 2016, the maximum number of state ratifications that a multilateral treaty can have is usually 197; this total consists of all 193 UN member states; both UN observers, the Holy See and State of Palestine; and the Cook Islands and Niue. If supranational or other international organizations ratify the treaty, the total number of ratifications may exceed 197.Legal effect of a high number of ratifications
When a treaty is ratified by nearly all recognized states in the world, the legal principles contained in the treaty may become customary international law. Customary international law applies to all states, whether or not the state has ratified a treaty that enshrines the principle. There is no set number of ratifications that are required to convert a treaty's principles into customary international law, and states and experts often disagree on what principles have and have not attained the status.List of treaties by number of parties
Below is the list of treaties by number of parties. Only treaties with a minimum of 170 parties are included.| Treaty | Year concluded | Topic | UN | Non-UN | States | Other | Total | Non-parties |
| Vienna Convention for the Protection of the Ozone Layer | 1985 | Environment | 193 | 4 | 197 | 1 | 198 | — |
| Montreal Protocol | 1987 | Environment | 193 | 3 | 197 | 1 | 198 | — |
| UN Framework Convention on Climate Change | 1992 | Environment | 193 | 3 | 196 | 1 | 197 | VAT |
| UN Convention to Combat Desertification | 1994 | Environment | 193 | 3 | 196 | 1 | 197 | VAT |
| Geneva Conventions: First, Second, Third, Fourth | 1949 | International humanitarian law | 193 | 3 | 196 | 0 | 196 | NIU |
| Convention on the Rights of the Child | 1989 | Human rights | 192 | 4 | 196 | 0 | 196 | USA |
| Convention on Biological Diversity | 1992 | Environment | 192 | 3 | 195 | 1 | 196 | VAT, USA |
| Constitution of the United Nations Educational, Scientific and Cultural Organisation | 1945 | Organizational ; education; science; culture | 192 | 3 | 195 | 0 | 195 | VAT, LIE |
| Constitution of the Food and Agriculture Organization | 1945 | Organizational ; agriculture; food | 192 | 2 | 194 | 1 | 195 | VAT, LIE, PSE |
| Constitution of the World Health Organization | 1946 | Organizational ; health | 191 | 2 | 193 | 0 | 193 | VAT, LIE, PSE |
| United Nations Charter | 1945 | Organizational ; pacific settlement of disputes | 193 | 0 | 193 | 0 | 193 | COK, VAT, NIU, PSE |
| Constitution and Convention of the International Telecommunication Union | 1865/1992 | Organizational ; telecommunications | 192 | 1 | 193 | 0 | 193 | COK, NIU, PLW, PSE |
| Convention concerning the Protection of the World Cultural and Natural Heritage | 1972 | Cultural and natural heritage | 189 | 4 | 193 | 0 | 193 | LIE, NRU, SOM, TUV |
| Chemical Weapons Convention | 1992 | Organizational ; international humanitarian law; arms control | 189 | 4 | 193 | 0 | 193 | EGY, ISR, PRK, SSD |
| Chicago Convention on International Civil Aviation | 1944 | Organizational ; air transport | 192 | 1 | 193 | 0 | 193 | VAT, LIE, NIU, PSE |
| Kyoto Protocol | 1997 | Environment | 189 | 2 | 191 | 1 | 192 | AND, CAN, VAT, PSE, SSD, USA |
| Vienna Convention on Diplomatic Relations | 1961 | Privileges and immunities; diplomatic relations | 190 | 2 | 192 | 0 | 192 | COK, NIU, PLW, SLB, SSD |
| WIPO Convention | 1967 | Organizational ; intellectual property | 189 | 3 | 192 | 0 | 192 | FSM, NRU, PLW, PSE, SSD |
| Treaty on the Non-Proliferation of Nuclear Weapons | 1968 | Arms control | 188 | 2 | 190 | 0 | 190 | COK, IND, ISR, NIU, PRK, PAK, SSD |
| UN Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances | 1988 | Drug control | 185 | 4 | 189 | 1 | 190 | GNQ, KIR, PLW, PNG, SLB, SOM, SSD, TUV |
| Convention on the Elimination of All Forms of Discrimination against Women | 1979 | Human rights | 187 | 2 | 189 | 0 | 189 | VAT, IRN, PLW, NIU, SOM, SDN, TON, USA |
| Articles of Agreement of the International Bank for Reconstruction and Development | 1944 | Organizational ; international development | 188 | 1 | 189 | 0 | 189 | AND, COK, CUB, VAT, LIE, MCO, NIU, PRK, PSE |
| United Nations Convention against Transnational Organized Crime | 2000 | Organized crime; international criminal law | 185 | 4 | 189 | 1 | 190 | BTN, COG, IRN, PNG, SLB, SOM, SSD, TUV |
| Articles of Agreement of the International Monetary Fund | 1944 | Organizational ; international development | 188 | 1 | 189 | 0 | 189 | AND, COK, CUB, VAT, LIE, MCO, NIU, PRK, PSE |
| Convention for the Suppression of Unlawful Acts against the Safety of Civil Aviation | 1971 | Aviation; terrorism | 186 | 2 | 188 | 0 | 188 | TLS, ERI, VAT, KIR, PSE, SMR, SOM, SSD, TUV |
| International Convention for the Suppression of the Financing of Terrorism | 1999 | Terrorism | 185 | 3 | 188 | 0 | 188 | BDI, TCD, ERI, IRN, LBN, PSE, SOM, SSD, TUV |
| Constitution of the Universal Postal Union | 1964 | Organizational ; postal | 186 | 1 | 187 | 0 | 187 | AND, DOM, HND, MHL, FSM, PLW, PSE, SDN |
| Constitution of the International Labour Organization | 1919/1945 | Organizational ; labour | 186 | 1 | 187 | 0 | 187 | AND, BHU, VAT, LIE, FSM, MCO, NIU, PRK, NRU, PSE |
| International Convention against Doping in Sport | 2005 | Doping in sport | 185 | 2 | 187 | 0 | 187 | |
| Basel Convention | 1992 | Environmental | 184 | 2 | 186 | 1 | 187 | TLS, FJI, GRD, HTI, VAT, NIU, SMR, SLB, SSD, TUV, USA |
| Tokyo Convention | 1969 | Terrorism, air transport | 184 | 2 | 186 | 0 | 186 | DMA, TLS, ERI, VAT, KIR, FSM, PSE, KNA, SOM, SSD, TUV |
| Single Convention on Narcotic Drugs | 1961 | Drug control | 184 | 2 | 186 | 0 | 186 | TCD, COK, TLS, GNQ, KIR, NRU, WSM, SSD, TUV, VUT |
| Paris Agreement | 2015 | Environment | 185 | 3 | 188 | 1 | 189 | |
| United Nations Convention against Corruption | 2003 | International criminal law | 181 | 4 | 185 | 1 | 186 | |
| Hague Hijacking Convention | 1970 | Terrorism, air transport | 183 | 2 | 185 | 0 | 185 | BDI, TLS, ERI, VAT, KIR, FSM, PSE, SMR, SLB, SOM, SSD, TUV |
| Articles of Agreement of the International Finance Corporation | 1955 | Organizational ; international development | 183 | 1 | 184 | 0 | 184 | AND, BRN, COK, CUB, VAT, LIE, MCO, NRU, NIU, PRK, PSE, SMR, VCT, TUV |
| Convention on Psychotropic Substances | 1971 | Drug control | 182 | 2 | 184 | 0 | 184 | COK, TLS, GNQ, HTI, KIR, LBR, NRU, WSM, SLB, SSD, TUV, VUT |
| CITES | 1973 | Environmental | 182 | 0 | 182 | 1 | 183 | |
| International Plant Protection Convention | 1951 | Agricultural | 180 | 2 | 182 | 1 | 183 | |
| Biological Weapons Convention | 1972 | International humanitarian law; arms control | 179 | 4 | 183 | 0 | 183 | |
| Worst Forms of Child Labour Convention | 1999 | Human rights; labour | 185 | 1 | 186 | 0 | 186 | |
| Stockholm Convention on Persistent Organic Pollutants | 2001 | Environmental | 180 | 3 | 183 | 1 | 184 | |
| Convention establishing the Multilateral Investment Guarantee Agency | 1985 | Organizational ; international development | 180 | 1 | 181 | 0 | 181 | |
| WHO Framework Convention on Tobacco Control | 2003 | Health | 178 | 2 | 180 | 1 | 181 | |
| Vienna Convention on Consular Relations | 1963 | Privileges and immunities; diplomatic relations | 178 | 2 | 180 | 0 | 180 | |
| Convention on the Prevention and Punishment of Crimes against Internationally Protected Persons, including Diplomatic Agents | 1973 | Anti-terrorism; privileges and immunities; diplomatic relations | 177 | 3 | 180 | 0 | 180 | |
| International Convention on the Elimination of All Forms of Racial Discrimination | 1969 | Human rights | 177 | 2 | 179 | 0 | 179 | |
| Forced Labour Convention | 1930 | Human rights; labour | 177 | 1 | 178 | 0 | 178 | |
| Convention for the Safeguarding of the Intangible Cultural Heritage | 2003 | Cultural heritage | 177 | 1 | 178 | 0 | 178 | |
| Convention on the Prevention and Punishment of Crimes against Internationally Protected Persons, including Diplomatic Agents | 1973 | Terrorism; privileges and immunities; diplomatic relations; international criminal law | 175 | 2 | 177 | 0 | 177 | |
| Paris Convention for the Protection of Industrial Property | 1883 | Intellectual property | 176 | 1 | 177 | 0 | 177 | |
| Convention on the Rights of Persons with Disabilities | 2006 | Human rights | 178 | 2 | 180 | 1 | 181 | |
| Agreement establishing the International Fund for Agricultural Development | 1976 | Organizational ; development | 174 | 2 | 176 | 0 | 176 | |
| International Convention against the Taking of Hostages | 1979 | Terrorism | 175 | 1 | 176 | 0 | 176 | |
| Berne Convention for the Protection of Literary and Artistic Works | 1886 | Intellectual property | 173 | 3 | 176 | 0 | 176 | |
| Convention establishing a Customs Co-operation Council | 1950 | Organizational ; customs | 175 | 0 | 175 | 0 | 175 | |
| Protocol for the Suppression of Unlawful Acts of Violence at Airports serving International Civil Aviation | 1988 | aviation; terrorism | 173 | 2 | 175 | 0 | 175 | |
| Discrimination Convention | 1958 | Human rights; labour | 175 | 0 | 175 | 0 | 175 | |
| Optional Protocol to the Convention on the Rights of the Child on the Sale of Children, Child Prostitution and Child Pornography | 2000 | Human rights | 173 | 2 | 175 | 0 | 175 | |
| Protocol I | 1977 | International humanitarian law | 171 | 3 | 174 | 0 | 174 | |
| Convention on the International Maritime Organization | 1948 | Organizational ; admiralty law; law of the sea | 173 | 1 | 174 | 0 | 174 | |
| Articles of Agreement of the International Development Association | 1960 | Organizational ; international development | 172 | 1 | 173 | 0 | 173 | |
| Abolition of Forced Labour Convention | 1957 | Human rights; labour | 172 | 1 | 173 | 0 | 173 | |
| Equal Remuneration Convention | 1951 | Human rights; labour | 173 | 0 | 173 | 0 | 173 | |
| Protocol to Prevent, Suppress and Punish Trafficking in Persons, especially Women and Children | 2000 | Human rights; international criminal law | 171 | 1 | 172 | 1 | 173 | |
| International Covenant on Civil and Political Rights | 1966 | Human rights | 171 | 1 | 172 | 0 | 172 | |
| Statute of the International Atomic Energy Agency | 1956 | Peaceful use of nuclear energy | 170 | 1 | 171 | 0 | 171 | |
| Cartagena Protocol on Biosafety | 2000 | Environment | 169 | 2 | 171 | 1 | 172 | |
| Convention on Wetlands of International Importance especially as Waterfowl Habitat | 1971 | Environment | 170 | 0 | 170 | 0 | 170 | |
| International Convention for the Suppression of Terrorist Bombings | 1997 | Terrorism | 169 | 1 | 170 | 0 | 170 |