| Regimental number | 5638 |
| Place of birth | Antrim, Ireland |
| Religion | Presbyterian |
| Occupation | Labourer |
| Address | Wagga PO, Wagga, New South Wales |
| Marital status | Single |
| Age at embarkation | 22 |
| Next of kin | Mother, Mrs Ellen McMullan, The Garden, Carin Castle, Lisnahay, Co. Antrim, Ireland |
| Enlistment date | |
| Place of enlistment | Cootamundra, New South Wales |
| Rank on enlistment | Private |
| Unit name | 18th Battalion, 15th Reinforcement |
| AWM Embarkation Roll number | 23/35/3 |
| Embarkation details | Unit embarked from Sydney, New South Wales, on board HMAT A14 Euripides on |
| Rank from Nominal Roll | Private |
| Unit from Nominal Roll | 18th Battalion |
| Fate | Returned to Australia |
| Family/military connections | Brother: 5639 Pte Joseph Andrew McMULLAN, 18th Bn, died whilst a prisoner of war, 9 June 1917. |
| Other details |
War service: Western Front Medals: British War Medal, Victory Medal |
| Sources | NAA: B2455, McMULLAN William James |