The 3rd Battalion was decimated at Lone Pine but, after the withdrawal from Gallipoli and reorganization in Egypt the Battalion was redeployed to the Western Front in March 1916 and went into the line at Armentières. Hamilton was promoted corporal on 3 May and fought at the Battle of Pozières in July, the Battle of Mouquet Farm in August and Flers in November. He was promoted sergeant in May 1917 and that year his battalion served at Bullecourt and at the Menin Road and Broodseinde theatres of the Battle of Passchendale.