The United Nations Flag Code of 11 November 1952 governs the design and use of the United Nations flag. In particular, the Code defines the conditions under which the UN flag may be hoisted. The dimensions of the flag are defined as 2:3 or 3:5.

The United Nations Flag Code and Regulations of 1 January 1967, which remain in force, leave it up to the UN Member States to hoist the UN flag in public in order to show their support for the United Nations and to promote its principles and aims.

In practice, UN Member States have long regarded the UN flag as the emblem of this international organization. The UN flag is always flown at buildings where UN agencies are located (in Germany, for example, at the International Tribunal for the Law of the Sea in Hamburg, and at the UN Climate Change Secretariat in Bonn).

The UN flag is also displayed at federal buildings for visits of high-ranking UN representatives in order to show the same honour as shown to representatives of other states.