XII (Howitzer) Brigade, Royal Field Artillery was a brigade of the Royal Field Artillery which served in the First World War. It was originally formed with 43rd, 86th and 87th (Howitzer) Batteries, each equipped with 4.5-inch howitzers, and attached to 6th Infantry Division. In August 1914 it mobilised and in September was sent to the Continent with the British Expeditionary Force, where it saw service with 6th Division until broken up. 86th Battery was withdrawn in May 1915, and assigned to 127th (Howitzer) Brigade.