This study evaluated whether lifetime traumatic stress compared to deployment-related traumatic stress differentially affected the likelihood of insomnia in military personnel.Data were obtained from the Army Study to Assess Risk and Resilience in Servicemembers (unweighted N = 21,499; weighted N = 670,335; 18-61 years; 13.5% Female). DSM-5 criteria were applied to the Brief Insomnia Questionnaire to determine past month insomnia diagnostic status. A lifetime stress survey was used to assess traumatic stress encountered outside of the military, and a deployment-related stress survey assessed for various types of deployment-related traumatic stress.Adjusting for sex and psychiatric disorders, lifetime traumatic stress increased the prevalence for insomnia among those who endorsed combat death of close friend or relative, 1.021 (95% CI, 1.02-1.02), followed by those who reported other experiences that put them at risk of death or serious injury, 1.013 (95% CI, 1.01-1.01), whereas deployment-related traumatic stress showed that the prevalence for insomnia was highest for those who reported being sexually assaulted or raped, 1.059 (95% CI, 1.04-1.08), followed by those who endorsed being hazed or bullied by one or more members of their unit 1.042 (95% CI, 1.04-1.05).The cross-sectional nature of the assessment limits causal inferences and there was no clinician determined diagnosis for insomnia.Findings suggest that traumas over both one's lifetime and during deployment are associated with a higher prevalence for insomnia among Army soldiers. Results highlight the importance of considering both lifetime and deployment traumas into mental health assessment and treatment for active-duty soldiers.