The 9th/12th Royal Lancers was a cavalry regiment of the British Army, formed in 1960 by the amalgamation of the 9th Queen's Royal Lancers and the 12th Royal Lancers. In the later years of its existence, the regiment served as a formation reconnaissance regiment, equipped with the Combat Vehicle Reconnaissance (Tracked) family of vehicles and was attached to the 7th Armoured Brigade, the Desert Rats. The regiment was based in South Wigston, Leicestershire, along with its affiliated Territorial Army unit, B Squadron, The Royal Yeomanry. It was amalgamated with the Queen's Royal Lancers on 2 May 2015 to form the Royal Lancers

There are 13 cavalry Regiments of the British Army each with its own unique cap badge, regimental traditions, and history. Of the currently nine regular cavalry regiments, two serve as armoured regiments, three as armoured cavalry regiments, three as light cavalry, and one as a mounted ceremonial regiment. There are also four yeomanry regiments of the Army Reserve, of these, three serve as light cavalry and one as an armoured regiment. Each yeomanry light cavalry unit has been paired with a regular unit of the same role, the armoured yeomanry unit is paired with the two regular armoured units. All except the Household Cavalry are part of the British Army's Royal Armoured Corps.