How the UN Security Council works

The United Nations Security Council is the one part of the UN whose decisions every member state has agreed, in advance and in writing, to carry out.¹ It is also the part most often accused of doing nothing. Both things are true, and the reason for both is in its design.

Fifteen seats

The Council has fifteen members.¹ Five are permanent: China, France, Russia, the United Kingdom and the United States, the main victors of the Second World War, whose seats the Charter fixed in 1945 (China's seat passed to the People's Republic in 1971 and the Soviet seat to Russia in 1991).⁸ The other ten are elected by the General Assembly for two-year terms, five each year, and a country that has just served cannot be re-elected straight away.¹

The ten elected seats are shared out by region: five for Africa and Asia-Pacific together, one for Eastern Europe, two for Latin America and the Caribbean, and two for Western Europe and other states.³ The Council began with eleven members in 1945 and grew to fifteen in 1965, the only time its size has changed.³

The presidency of the Council rotates every month, in the English alphabetical order of the members' names.² The president chairs the meetings and signs the statements; the job carries no extra vote.

Nine votes, and the veto

Each member has one vote. A procedural question passes with nine votes out of fifteen. Anything that is not procedural also needs nine votes, but Article 27 adds a condition: the nine must include "the concurring votes of the permanent members".¹ That clause is the veto. The word itself appears nowhere in the Charter.

In practice it means a single "no" from China, France, Russia, the United Kingdom or the United States stops a resolution even if the other fourteen members vote yes. An abstention is different. Since 1946 the Council has treated a permanent member that abstains as not blocking a decision, and in 1971 the International Court of Justice confirmed that this practice is lawful.⁷ So a permanent member that dislikes a text but does not want to kill it can abstain, and the text passes.

The Soviet Union cast the first veto in 1946. The Soviet Union and Russia together have cast more vetoes than any other member, with the United States second; the library of the UN keeps the full list, by date and country.⁶ Since April 2022, every veto triggers a General Assembly debate within ten working days, at which the country that cast it is invited to explain itself. The veto still stands.⁵

What the Council can do

The Charter gives the Council two toolkits. Under Chapter VI it can investigate a dispute and recommend ways to settle it. Recommendations are advice; states are expected to take them seriously, but they are not orders.¹

Under Chapter VII the Council first decides, under Article 39, that there is a threat to the peace, a breach of the peace or an act of aggression. It can then impose measures "not involving the use of armed force", which is the legal basis for sanctions, arms embargoes and asset freezes (Article 41), and if those are not enough it can authorise action "by air, sea, or land forces" (Article 42).¹ Article 25 is what gives Chapter VII decisions their weight: all members "agree to accept and carry out the decisions of the Security Council".¹

Peacekeeping, the blue helmets most people associate with the UN, is not mentioned in the Charter by name. It grew out of practice, usually with the consent of the country where the mission is deployed.

What the Council cannot do

It cannot get round a veto. When the Council is blocked, the General Assembly can meet under the 1950 "Uniting for Peace" procedure and recommend collective measures, but Assembly recommendations do not bind anyone.⁴

It cannot reform itself without the five. Amending the Charter needs a two-thirds vote in the General Assembly and then ratification by two thirds of all members, including every permanent member (Article 108).¹ Each of the five can therefore veto any change to the veto.

How to read a Council vote

Three things tell you most of what you need to know. First, the count: fifteen to nothing is a different signal from nine in favour, none against and six abstentions, even though both pass. Second, the chapter: a text that "decides" under Chapter VII is binding; one that "calls upon" or "urges" is a recommendation. Third, the form: a presidential statement needs the agreement of all fifteen members and is not a resolution, and a press statement is weaker still.²

When a resolution fails, look at who voted no. If it is one of the five, it was a veto. If it is anyone else, the text simply did not reach nine votes, which happens less often and tells you something different about the room.

Last checked against the Charter text and the Security Council's own pages on 6 November 2026. This explainer is evergreen: it describes the rules, not any particular vote. This piece has not yet been checked by a second person.

Sources

1. Charter of the United Nations (signed 26 June 1945, in force 24 October 1945), Chapter V (Articles 23 to 32), Chapter VI, Chapter VII (Articles 39 to 42), Article 108. United Nations, un.org/en/about-us/un-charter.
2. United Nations Security Council, "Current Members", "Voting System" and "Presidency", un.org/securitycouncil.
3. UN General Assembly resolution 1991 A (XVIII), 17 December 1963, which enlarged the Council from eleven to fifteen members and set the regional pattern for elected seats; in force 31 August 1965.
4. UN General Assembly resolution 377 A (V), "Uniting for Peace", 3 November 1950.
5. UN General Assembly resolution 76/262, 26 April 2022, a standing mandate for a General Assembly debate within ten working days of a veto.
6. Dag Hammarskjöld Library, "Security Council Veto List", research.un.org (every veto since 1946, by country and date).
7. International Court of Justice, advisory opinion on the Legal Consequences for States of the Continued Presence of South Africa in Namibia, 21 June 1971, paragraph 22, on abstention under Article 27.
8. United Nations, "Member States" (un.org/en/about-us/member-states), notes on China (General Assembly resolution 2758 (XXVI), 25 October 1971) and on the Russian Federation (letter of 24 December 1991 by which Russia continued the Soviet Union's membership of the UN and its seat on the Security Council).

Corrections. None yet. If you find an error, write to [email protected]. Every correction is logged here with its date.