World · permanent entity record · IO
British Indian Ocean Territory
Thirty-second orientation
British Indian Ocean Territory at a glance
- Capital
- name: administered from London; often regarded as being on Diego Garcia geographic coordinates: 7 18S, 12 24E time difference: UTC+6 (12 hours ahead of Washington, DC, during Standard Time)
- CIA World Factbook historical record · as of 2026-01-08
- Population
- total: no permanent inhabitants note: Diego Garcia, the largest of the 58 islands, hosts a joint UK-US military facility
- CIA World Factbook historical record · as of 2026-01-08
- Area
- total : 60 sq km land: 60 sq km (44 Diego Garcia) water: 54,340 sq km note: includes the entire Chagos Archipelago of 55 islands
- CIA World Factbook historical record · as of 2026-01-08
Claims are attributed · classifications are dated
Claims and contested status
Maintained classification
Dependency or area of special sovereignty
United Kingdom
U.S. Department of State, Dependencies and Areas of Special Sovereignty · as of 2026-03-31A claim’s appearance records that the cited source reports it. It does not constitute an Almanac ruling on sovereignty.
Maintained profile
- Classification
- Dependency or area of special sovereignty
- U.S. Department of State, Dependencies and Areas of Special Sovereignty · Federal classification and wording follow the current State Department register.
- Sovereignty or administration
- United Kingdom
- U.S. Department of State, Dependencies and Areas of Special Sovereignty ·
Preserved public-domain record · not maintained current data
Final CIA World Factbook profile
This is the preserved historical baseline from the Factbook’s final public snapshot. It is presented as the CIA stated it, not as a current Standard American Almanac finding. Current, independently maintained facts appear above when available.
CIA World Factbook historical record · final public snapshot · profile updated · pinned source record · commit d81154954b8b
Introduction1 fields
- Background
- Formerly administered as part of the British Crown Colony of Mauritius, the British Indian Ocean Territory (BIOT) was established as an overseas territory of the UK in 1965. A number of the islands in the territory were later transferred to the Seychelles when it gained independence in 1976. Subsequently, BIOT has consisted of the six main island groups that make up the Chagos Archipelago. Only Diego Garcia, the largest and most southerly of the islands, is inhabited. It contains a joint UK-US naval support facility and hosts one of four dedicated ground antennas that assist in the operation of the Global Positioning System (GPS) navigation system -- the others are on Kwajalein (Marshall Islands); at Cape Canaveral, Florida (US); and on Ascension Island (Saint Helena, Ascension, and Tristan da Cunha). The US Air Force also operates a telescope array on Diego Garcia as part of the Ground-Based Electro-Optical Deep Space Surveillance System (GEODSS) for tracking orbital debris, which can be a hazard to spacecraft and astronauts. Between 1967 and 1973, the former agricultural workers who lived on the islands were relocated, primarily to Mauritius but also to the Seychelles. Negotiations with the UK between 1971 and 1982 resulted in the establishment of a trust fund to compensate the displaced islanders, known as Chagossians. Beginning in 1998, the islanders pursued a series of lawsuits against the British Government, seeking further compensation and the right to return to the territory. British court rulings in 2006 and 2007 invalidated immigration policies that had excluded the islanders from the archipelago, but in 2008, the House of Lords -- the final court of appeal in the UK -- ruled in favor of the British Government by overturning the lower court rulings and finding no right of return for the Chagossians. In 2015, the Permanent Court of Arbitration unanimously held that the marine protected area that the UK declared around the Chagos Archipelago in 2010 violated the UN Convention on the Law of the Sea. In 2019, the International Court of Justice ruled in an advisory opinion that Britain’s decolonization of Mauritius was not lawful because of continued Chagossian claims. A non-binding 2019 UN General Assembly vote demanded that Britain end its “colonial administration” of the Chagos Archipelago and that it be returned to Mauritius. On 22 May 2025, the United Kingdom and Mauritius signed an agreement that will lead to the transfer of sovereignty of the Chagos Archipelago to Mauritius. Under the agreement, the United Kingdom will lease Diego Garcia from Mauritius for 99 years and maintain full operational control of the joint UK-US military base.
- CIA World Factbook historical record · as of · source
Geography15 fields
- Location
- archipelago in the Indian Ocean, south of India, about halfway between Africa and Indonesia
- CIA World Factbook historical record · as of · source
- Geographic coordinates
- 6 00 S, 71 30 E note: Diego Garcia 7 20 S, 72 25 E
- CIA World Factbook historical record · as of · source
- Area
- total : 60 sq km land: 60 sq km (44 Diego Garcia) water: 54,340 sq km note: includes the entire Chagos Archipelago of 55 islands
- CIA World Factbook historical record · as of · source
- Area - comparative
- land area is about one-third the size of Washington, D.C.
- CIA World Factbook historical record · as of · source
- Maritime claims
- territorial sea: 12 nm Environment (Protection and Preservation) Zone: 200 nm
- CIA World Factbook historical record · as of · source
- Climate
- tropical marine; hot, humid, moderated by trade winds
- CIA World Factbook historical record · as of · source
- Terrain
- flat and low coral atolls (most areas do not exceed 2 m, or 6.6 ft, in elevation); sits atop the submarine volcanic Chagos-Laccadive Ridge
- CIA World Factbook historical record · as of · source
- Elevation
- highest point: ocean-side dunes on Diego Garcia 9 m lowest point: Indian Ocean 0 m
- CIA World Factbook historical record · as of · source
- Land use
- agricultural land: 0% (2018 est.) arable land: 0% (2018 est.) permanent crops: 0% (2018 est.) permanent pasture: 0% (2018 est.) forest: 0% (2018 est.) other: 100% (2018 est.)
- CIA World Factbook historical record · as of · source
- Natural hazards
- none; located outside routes of Indian Ocean cyclones
- CIA World Factbook historical record · as of · source
- Geography - note
- note 1: archipelago of 55 islands; Diego Garcia, the largest and southernmost island, occupies a strategic location in the central Indian Ocean note 2: Diego Garcia is the only inhabited island of the BIOT
- CIA World Factbook historical record · as of · source
People and Society1 fields
- Population
- total: no permanent inhabitants note: Diego Garcia, the largest of the 58 islands, hosts a joint UK-US military facility
- CIA World Factbook historical record · as of · source
Environment3 fields
- Environmental issues
- wastewater discharge into the lagoon on Diego Garcia
- CIA World Factbook historical record · as of · source
- Climate
- tropical marine; hot, humid, moderated by trade winds
- CIA World Factbook historical record · as of · source
- Land use
- agricultural land: 0% (2018 est.) arable land: 0% (2018 est.) permanent crops: 0% (2018 est.) permanent pasture: 0% (2018 est.) forest: 0% (2018 est.) other: 100% (2018 est.)
- CIA World Factbook historical record · as of · source
Government11 fields
- Country name
- conventional long form: British Indian Ocean Territory conventional short form: none abbreviation: BIOT etymology: self-descriptive name specifying the territory's affiliation and location
- CIA World Factbook historical record · as of · source
- Dependency status
- overseas territory of the UK; administered by a commissioner, resident in the Foreign, Commonwealth, and Development Office in London
- CIA World Factbook historical record · as of · source
- Capital
- name: administered from London; often regarded as being on Diego Garcia geographic coordinates: 7 18S, 12 24E time difference: UTC+6 (12 hours ahead of Washington, DC, during Standard Time)
- CIA World Factbook historical record · as of · source
- Constitution
- history: British Indian Ocean Territory (Constitution) Order 2004
- CIA World Factbook historical record · as of · source
- Executive branch
- chief of state: King CHARLES III (since 8 September 2022) head of government: Commissioner Nishi DHOLAKIA (since 16 December 2024); Administrator Bob FAIRWEATHER; both reside in the UK and are represented by Commander Andrew WILLIAMS, RN, the officer commanding British Forces on Diego Garcia (since January 2025) cabinet: NA election/appointment process: the monarchy is hereditary; commissioner and administrator appointed by the monarch
- CIA World Factbook historical record · as of · source
- Diplomatic representation in the US
- none (overseas territory of the UK)
- CIA World Factbook historical record · as of · source
- Diplomatic representation from the US
- embassy: none (overseas territory of the UK)
- CIA World Factbook historical record · as of · source
- Flag
- description: white with six wavy blue horizontal stripes; the UK flag is in the upper-left quadrant; the striped section has a palm tree and yellow crown (the territory's symbols) centered on the right half of the flag meaning: the wavy stripes represent the Indian Ocean; the six blue stripes may stand for the six main atolls of the archipelago
- CIA World Factbook historical record · as of · source
- National anthem(s)
- title: "God Save the King" lyrics/music: unknown history: official anthem, as a UK overseas territory
- CIA World Factbook historical record · as of · source
Economy6 fields
- Economic overview
- small island territory economy; economic activity mainly on Diego Garcia with national military installations; recently settled disputes with Mauritius have increased oil exports; established marine reserve has limited commercial fishing
- CIA World Factbook historical record · as of · source
- Exports - partners
- Singapore 86%, Pakistan 8%, USA 1%, South Africa 1%, Czechia 1% (2023) note: top five export partners based on percentage share of exports
- CIA World Factbook historical record · as of · source
- Exports - commodities
- fish (2023) note: top export commodities based on value in dollars over $500,000
- CIA World Factbook historical record · as of · source
- Imports - partners
- Greece 52%, Singapore 38%, USA 4%, Panama 2%, UAE 2% (2023) note: top five import partners based on percentage share of imports
- CIA World Factbook historical record · as of · source
- Imports - commodities
- refined petroleum, animal products, aluminum structures, insulated wire, prefabricated buildings (2023) note: top five import commodities based on value in dollars
- CIA World Factbook historical record · as of · source
Communications3 fields
- Broadcast media
- Armed Forces Radio and Television Service (AFRTS) broadcasts over 3 frequencies for US and UK military personnel stationed on the islands
- CIA World Factbook historical record · as of · source
- Communications - note
- Diego Garcia hosts one of four dedicated ground antennas that assist in the operation of the Global Positioning System (GPS) navigation system (the others are on Kwajalein (Marshall Islands), at Cape Canaveral, Florida (US), and on Ascension Island (Saint Helena, Ascension, and Tristan da Cunha))
- CIA World Factbook historical record · as of · source
Transportation2 fields
- Ports
- total ports: 1 (2024) large: 0 medium: 0 small: 0 very small: 1 ports with oil terminals: 1 key ports: Diego Garcia
- CIA World Factbook historical record · as of · source
Military and Security2 fields
- Military and security forces
- no regular military forces
- CIA World Factbook historical record · as of · source
- Military - note
- defense is the responsibility of the UK; on 22 May 2025, the United Kingdom and Mauritius signed an agreement that will lead to the transfer of sovereignty of the Chagos Archipelago to Mauritius; under the agreement, the United Kingdom will lease Diego Garcia from Mauritius for 99 years and maintain full operational control of the joint UK-US military base
- CIA World Factbook historical record · as of · source
The underlying United States government material is public domain. The Almanac’s reuse terms do not change the legal status of this preserved source layer.