The British Army is the land armed forces branch of the British Armed Forces. It came into being with unification of the governments and armed forces of England and Scotland into the United Kingdom of Great Britain in 1707. The new British Army incorporated regiments that had already existed in England and Scotland and was controlled by the War Office from London. As of April, 2007, the British Army includes roughly 110,580 regular personnel and 38,460 Territorial Army members. The full time element of the British Army has also been referred to as the Regular Army since the creation of the reservist Territorial Army. The British Army is deployed in many of the world's war zones as part of a fighting force and in United Nations peacekeeping forces.

In contrast to the Royal Navy, Royal Marines and Royal Air Force, the British Army does not include "Royal" in its title, because of its roots as a collection of disparate units, many of which do bear the "Royal" prefix, such as the Royal Artillery and the Royal Engineers.