"Chink", along with the rest of his battalion, then serving as part of the 9th Brigade of the 3rd Division, was sent to France on 13 August 1914, nine days after Britain entered the First World War. He was among the first troops of the British Expeditionary Force (BEF) to arrive. The battalion, and Dorman-Smith himself, were involved in the Battle of Mons, where he was wounded in the retreat. Later that year he was involved in the battles of Messines, Armentières and Ypres and, after being promoted on 15 November to the temporary rank of lieutenant, received another wound on 9 December. He was promoted to substantive lieutenant on 2 January 1915.