| Regimental number | 2587 |
| Date of birth | |
| Place of birth | Norwood, South Australia |
| Religion | Methodist |
| Occupation | Clerk |
| Address | Rankine Street, Torrensville, South Australia |
| Marital status | Single |
| Age at embarkation | 23 |
| Height | 5' 10" |
| Weight | 145 lbs |
| Next of kin | Father, S Everden Siggs, Rankine Street, Torrensville, South Australia |
| Previous military service | Nil |
| Enlistment date | |
| Place of enlistment | Keswick, South Australia |
| Rank on enlistment | Private |
| Unit name | 16th Battalion, 8th Reinforcement |
| AWM Embarkation Roll number | 23/33/3 |
| Embarkation details | Unit embarked from Adelaide, South Australia, on board RMS Morea on |
| Regimental number from Nominal Roll | R2587 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | Australian Flying Corps |
| Fate | Returned to Australia |
| Discharge date | |
| Family/military connections | Brother: 3481 Pte Eric Evernden SIGGS, 50th Bn, killed in action, 26 September 1917. |
| Other details |
Commenced return to Australia on board HT 'Kaisar-i-Hind', 6 May 1919; disembarked Adelaide, 14 June 1919; discharged (termination of period of enlistment), Adelaide, 29 July 1919. Medals: 1914-15 Star, British War Medal, Victory Medal |
| Date of death | |
| Age at death | 87 |
| Place of burial | Centennial Park Cemetery, Adelaide, South Australia |
| Sources | NAA: B2455, SIGGS William Harold |