| Regimental number | 5658 |
| Place of birth | Sydney New South Wales |
| Religion | Roman Catholic |
| Occupation | Wood machinist |
| Address | 322 Parramatta, Road Annandale, Sydney, New South Wales |
| Marital status | Single |
| Age at embarkation | 19 |
| Next of kin | Father, J J Byrnes, 322 Parramatta Road Annandale, Sydney, New South Wales |
| Enlistment date | 17 January 1916 |
| Rank on enlistment | Private |
| Unit name | 1st Battalion, 18th Reinforcement |
| AWM Embarkation Roll number | 23/18/4 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A55 Kyarra on 3 June 1916 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 1st Battalion |
| Fate | Returned to Australia 18 December 1918 |
| Miscellaneous details (Nominal Roll) | *Given name William Harold |
| Date of death | 28 October 1964 |
| Place of burial | Field of Mars Cemetery |