| Regimental number | 1650 |
| Place of birth | Launceston, Tasmania |
| School | State School, Invermay, Tasmania |
| Religion | Church of England |
| Occupation | Labourer |
| Address | Frank Street, Invermay, Tasmania |
| Marital status | Widower |
| Age at embarkation | 26 |
| Next of kin | Mother, Mrs S Thomas, Frank Street, Invermay, Tasmania |
| Enlistment date | 10 December 1914 |
| Rank on enlistment | Private |
| Unit name | 12th Battalion, 3rd Reinforcement |
| AWM Embarkation Roll number | 23/29/2 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board HMAT A54 Runic on 19 February 1915 |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 12th Battalion |
| Other details from Roll of Honour Circular | Name given on RoH circular as Harry David THOMAS. |
| Fate | Killed in Action 4 June 1916 |
| Place of death or wounding | France |
| Age at death | 27 |
| Family/military connections | Brothers: Pte H W THOMAS, 4th Machine Gun Company, killed in action, 11 April 1917; Lt C E THOMAS MID, returned to Australia. |