| Other Names | DAY, William John~ |
| Religion | Presbyterian |
| Occupation | Farmer |
| Address | Augustown via Nagambie, Victoria |
| Marital status | Married |
| Age at embarkation | 36 |
| Next of kin | Wife, Mrs E C Day, Augustown via Nagambie, Victoria |
| Previous military service | 15th Light Horse |
| Enlistment date | 21 September 1914 |
| Rank on enlistment | Captain |
| Unit name | 8th Light Horse Regiment, A Squadron |
| AWM Embarkation Roll number | 10/13/1 |
| Embarkation details | Unit embarked from Melbourne, Victoria, on board Transport A16 Star of Victoria on 25 February 1915 |
| Rank from Nominal Roll | Major |
| Unit from Nominal Roll | 4th Light Horse Regiment |
| Fate | Returned to Australia 6 August 1918 |
