| Regimental number | 606 |
| Place of birth | Newtown, Sydney, New South Wales |
| School | Beaconsfield State School, Western Australia |
| Religion | Church of England |
| Occupation | Porter |
| Address | Sydney Street, South Fremantle, Western Australia |
| Marital status | Single |
| Age at embarkation | 18 |
| Next of kin | Father, Edward Coolahan, Sydney Street, South Fremantle, Western Australia |
| Previous military service | Served in Senior Cadets B Coy 86th Bn, Fremantle. |
| Enlistment date | |
| Date of enlistment from Nominal Roll | |
| Rank on enlistment | Private |
| Unit name | 28th Battalion, B Company |
| AWM Embarkation Roll number | 23/45/1 |
| Embarkation details | Unit embarked from Fremantle, Western Australia, on board HMAT A11 Ascanius on |
| Embarkation details | Unit embarked from Fremantle, Western Australia, on board HMAT A36 Thirty Six on |
| Rank from Nominal Roll | Sergeant |
| Unit from Nominal Roll | 28th Battalion |
| Fate | Died of wounds |
| Place of death or wounding | Passchendaele, Ypres, Belgium |
| Age at death | 20 |
| Place of burial | Bologne Eastern Cemetery (Plot VIII, Row I, Grave No. 109), France |
| Panel number, Roll of Honour, Australian War Memorial | 112 |
| Miscellaneous information from cemetery records | Parents: Edward and Maud COOLAHAN, Sydney Street, South Fremantle, Western Australia. Native of Newtown, Sydney, New South Wales |
| Family/military connections | Cousins: Pte W. CHAPLAIN, 20th Bn, killed in action; 3821 Pte Leslie Roland HILL, 11th Bn, killed in action, 30 May 1916. |
| Other details |
Medals: 1914-15 Star, British War Medal, Victory Medal |