A Chief Minister is the elected head of government of a sub-national (e.g. constituent federal) state, notably a state (and sometimes a union territory) of India, a territory of Australia or a British overseas territory that has attained self-government. It is also used as the English version of the title given to the heads of governments of the Malay states without a monarchy.

The title is also used in the Crown dependencies of the Isle of Man (since 1986), in Guernsey (since 2004), and in Jersey (since 2005).

In Malaysia, it is used to refer to the heads of government, called in their Malay language term Ketua Menteri (literally Chief Minister), of the Malaysian states without a sultan, i.e., Malacca, Penang, Sabah and Sarawak, while the Malay language term Menteri Besar (literally Great Minister) is used in other states with a monarch.

By analogy the term is often applied to various other high ministerial offices, e.g. in a princely state before or during the British raj.