A British High Commission is a British diplomatic mission, equivalent to an embassy, found in countries that are members of the Commonwealth of Nations. Their general purpose is to provide diplomatic relationships as well as travel information, passports, dual-citizenship information, and other services between Commonwealth states. Where some Commonwealth countries are not represented in another Commonwealth country, the British High Commission can assist such Commonwealth countries' citizens in some cases. William Henry Clark served as Britain's first high commissioner (1928–1934), sent to Ottawa at the request of the Canadian prime minister in the aftermath of the King–Byng affair and the Balfour Declaration of 1926. Appointed by the Dominions Office, the High Commissioner to Canada assumed the governor general's role as agent of the British government. Some countries that were outside the Commonwealth, but have now returned to their membership of the Commonwealth, have replaced their embassies and ambassadors with High Commissions and High Commissioners.

List of British High Commissions and British High Commissioners