A billet is the US term for quarters, which is a place to which a person, generally a soldier, is assigned to sleep. In the European countries since formation of regular forces the Quartermaster was an occupation and a rank of the individuals responsible for provision of sleeping quarters as well as other provisions for regular time troops. Soldiers are generally billeted in barracks or garrisons when not on combat duty, although in some armies soldiers with families are permitted to maintain a home off-post. Used for a building, the term is more commonly used in British English; United States standard terms are quarters, barracks, "Single (Soldier) Housing" or "Family Housing". The expression 'billet' is also used for an exchange student.
One of the major grievances of the American colonists against the British government which led to the American Revolutionary War was the quartering of soldiers in civilian homes. As a result, the Third Amendment to the United States Constitution provides restrictions on the manner in which the Federal government of the United States may require civilians to provide housing for American soldiers.
In Spain the noble officers of royal tercios were billeted in the homes of the affluent and well-to-do of the cities/towns they were stationed in. This usage is employed as a plot device in the Barber of Seville.
During wartime, civilians who have been evacuated from a city in danger of attack are billetted in communal shelters or in the homes of individuals. The practice of billetting evacuees was widespread in Britain during World War II, particularly during the Blitz, when children and other non-essential persons in major cities were sent to rural areas for safety.
Billet can also mean a personnel position, assignment, or duty station which may be filled by one person, commonly used by the United States Navy and the United States Marine Corps. It may also refer in all the armed forces to the individual bunk or bed.
Billet can also refer to the position and weapons of the members of a unit. For example, the billets of a fireteam include a fireteam leader (M16), a rifleman (M16), an automatic rifleman (M249), and an assistant automatic rifleman (M16).