Lilley joined the New Zealand Permanent Force when he was 19, on 1 August 1902. He served mostly at Alexandra Military Depot at Wellington as a Gunner, followed by Bombardier. He was based at Wellington until 6 February 1917, when he transferred to the NZEF. (Church, p.212)

A year after leaving New Zealand with the NZEF Lilley was admitted to the University War Hospital, Southhampton, England. He was placed on the Seriously Ill list suffering from cellulitis on the face, and died on 24 April 1918. (Church, p.212) AWMM