Military branches:
Army, Royal Navy (includes Royal Marines), Royal Air Force (2010)

Military service age and obligation:
16-33 years of age (officers 17-28) for voluntary military service (with parental consent under 18); women serve in military services, but are excluded from ground combat positions and some naval postings; as of October 2009, women comprised 12.1% of officers and 9% of enlisted personnel in the regular forces; must be citizen of the UK, Commonwealth, or Republic of Ireland; reservists serve a minimum of 3 years, to age 45 or 55; 16 years of age for voluntary military service by Nepalese citizens in the Brigade of Gurkhas; 16-34 years of age for voluntary military service by Papua New Guinean citizens (2009)

Manpower available for military service:
males age 16-49: 14,732,445
[see also: Manpower available for military service - males age 16-49 country ranks ]
females age 16-49: 14,118,320 (2010 est.)
[see also: Manpower available for military service - females age 16-49 country ranks ]

Manpower fit for military service:
males age 16-49: 12,113,310
[see also: Manpower fit for military service - males age 16-49 country ranks ]
females age 16-49: 11,604,784 (2010 est.)
[see also: Manpower fit for military service - females age 16-49 country ranks ]

Manpower reaching military service age annually:
male: 386,492
[see also: Manpower reaching military service age annually - male country ranks ]
female: 369,185 (2010 est.)
[see also: Manpower reaching military service age annually - female country ranks ]

Military expenditures:
2.4% of GDP (2005 est.)
country comparison to the world: 62
[see also: Military expenditures country ranks ]