Exposure to traumatic events is common among individuals with substance use disorders (SUD), although not all go on to develop PTSD. We compared SUD treatment outcomes and relapse features in three groups of male veterans receiving SUD treatment: (1) those without trauma exposure (SUD-only; n=68), (2) those with PTSD (SUD-PTSD; n=32), and (3) those with trauma exposure but no PTSD (SUD-trauma; n=34). Veterans were assessed regarding psychiatric symptoms, substance use, and relapse features quarterly for 1 year. The groups did not differ on length of abstinence, relapse prevalence or severity. SUD-PTSD and SUD-trauma reported more depression, anxiety, PTSD, and total psychiatric symptoms prior to relapse than SUD-only. SUD-PTSD and SUD-trauma also endorsed more PTSD, and total symptoms following relapse than SUD-only. PTSD symptoms were associated with greater risk of relapse in intrapersonal and negative physiological contexts. Understanding relapse contexts for those experiencing PTSD symptoms can help us to understand one mechanism whereby those with both PTSD and SUD have a poorer clinical course.