The Guards Machine Gun Regiment was a regiment of the British Army, formed for service in the First World War. When the Guards Division was formed in August 1915, it included three machine gun companies, with a fourth added in March 1917. In April 1917, the four companies were grouped together as a single battalion named the Machine Gun Guards, before being re-designated by Royal Warrant in May 1918 as the Guards Machine Gun Regiment. In June, the regiment was reorganised into battalions: