XLIII (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 30th, 40th and 57th (Howitzer) Batteries, each equipped with 4.5-inch howitzers, and attached to 1st Infantry Division. In August 1914 it mobilised and was sent to the Continent with the British Expeditionary Force, where it saw service with 1st Division until broken up. 57th Battery was withdrawn in May 1915, and assigned to 128th (Howitzer) Brigade.