| Regimental number | 2265 |
| Place of birth | Elsternwick Victoria |
| Religion | Presbyterian |
| Occupation | Electrical engineer |
| Address | Brunswick, Victoria |
| Marital status | Single |
| Age at embarkation | 19 |
| Next of kin | Father, John Marshall O'Neill, 63 Park Street, East Brunswick, Victoria |
| Previous military service | 60th Infantry |
| Enlistment date | 5 May 1917 |
| Date of enlistment from Nominal Roll | 3 May 1917 |
| Rank on enlistment | 2nd Air Mechanic |
| Unit name | August 1917 Reinforcements |
| AWM Embarkation Roll number | 8/15/2 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board HMAT A29 Suevic on 21 June 1917 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board HMAT A32 Themistocles on 4 August 1917 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board HMAT A60 Aeneas on 30 October 1917 |
| Rank from Nominal Roll | Corporal |
| Unit from Nominal Roll | 6th Training Squadron Australian Flying Corps |
| Fate | Returned to Australia 23 March 1919 |
