United Kingdom

National in-service fixed-wing aircraft classified as Combat aircraft by FlightGlobal/Cirium, summing the Active column across all military services listed for the country. Excludes the separately classified trainers, special-mission aircraft, tankers and helicopters, as well as aircraft in storage, undergoing or awaiting upgrades, and orders. This is the directory's active-role inventory estimate, not a measure of combat readiness.

British national Challenger 2 main battle tank fleet in FOI's 2023 capability assessment. Does not add the separately planned Challenger 3 upgrade programme or broader later inventory holdings.

National in-service fixed-wing military transport aircraft classified as Transport by FlightGlobal/Cirium, summing the Active column across all military services listed for the country. Includes strategic, tactical and light liaison/utility transport aircraft; excludes the separately classified trainers, special-mission aircraft, tankers and helicopters, as well as aircraft in storage, undergoing or awaiting upgrades, and orders. This is the directory's active-role inventory estimate, not a measure of immediate availability.

2020 annual observation. Active-duty military personnel, including qualifying paramilitary forces; not an active-regular-only count.

Total trained and untrained UK Tri-Service Future Reserves 2020 personnel. Includes FR20 volunteer reserve categories; excludes the wider former-regular mobilisation liability pool.

Commissioned cruisers, destroyers and frigates in the national fleet; excludes aircraft carriers, corvettes, patrol, amphibious and support vessels. Fleet count, not immediately deployable strength.

Royal Navy Submarine Service vessels in service at 1 April 2026, under MOD readiness-state definition; not necessarily immediately deployable.

Warheads in the military stockpile: in the custody of the military and earmarked for use by military forces, deployed or in reserve. Excludes retired warheads awaiting dismantlement.