| Regimental number | 17981 |
| Date of birth | 12 September 1886 |
| Place of birth | Adaminaby, New South Wales |
| Other Names | HARNETT, Reginald Finlay |
| Religion | Roman Catholic |
| Occupation | Surveyor's lineman |
| Address | Monaro, New South Wales |
| Marital status | Single |
| Age at embarkation | 30 |
| Height | 5' 11" |
| Weight | 174 lbs |
| Next of kin | Father, John Joseph Harnett, Bredbo, New South Wales |
| Enlistment date | 9 March 1917 |
| Place of enlistment | Sydney, New South Wales |
| Rank on enlistment | Sapper |
| Unit name | 1st and 2nd Field Troops |
| AWM Embarkation Roll number | 14/36/1 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A15 Port Sydney on 9 May 1917 |
| Rank from Nominal Roll | Sapper |
| Unit from Nominal Roll | 1st Field Squadron Engineers |
| Fate | Returned to Australia 17 July 1919 |
| Discharge date | 29 September 1919 |
| Family/military connections | Sister: Jessie Eleanor HARNETT, Australian Army Nursing Service |
| Other details | Medals: British War Medal, Victory Medal |
| Date of death | 6 August 1968 |
| Age at death | 82 |
| Place of burial | Frenchs Forest Cemetery, New South Wales |
| Sources | NAA: B2455, HARNETT Reginald Finley |