Lifetime suicidality was assessed in a cohort of 448 ageing Australian Vietnam veterans and 237 female partners during in-person structured psychiatric interviews that permitted direct comparison with age-sex matched Australian population statistics. Relative risks for suicidal ideation, planning and attempts were 7.9, 9.7 and 13.8 times higher for veterans compared with the Australian population and for partners were 6.2, 3.5 and 6.0 times higher. Odds ratios between psychiatric diagnoses and suicidality were computed using multivariate logistic regression, and suicidality severity scores were assigned from ideation, planning and attempt, and analysed using ordinal regression. PTSD, depression alcohol disorders, phobia and agoraphobia were prominent predictors of ideation, attempts and suicidal severity among veterans, while depression, PTSD, social phobia and panic disorder were prominent predictors among partners. For veterans and their partners, PTSD is a risk factor for suicidality even in the presence of other psychiatric disorders, and is stronger in Vietnam veterans than their partners.