Abstract: Military service members experience higher levels of cumulative trauma than the general population, increasing their risk of mental health problems. This scoping review synthesizes evidence on protective factors that contribute to posttraumatic wellbeing among military service members and veterans. PubMed and PsycINFO databases were searched using keywords for military/veterans, traumatic event exposure, posttraumatic stress, and wellbeing outcomes (e.g., quality of life [QoL]). Article abstracts and full texts were screened by two reviewers, with a third reviewer resolving conflicts. Inclusion criteria consisted of the following: (a) empirical study, (b) military/veteran sample, (c) exposed to posttraumatic stress disorder (PTSD) criterion A event, (d) ≥1 protective factor examined, (e) ≥1 wellbeing outcome examined. After data extraction, Bibliometric Network Analysis was used to visualize the topics covered. Literature searches yielded 1,341 articles. Of these, 104 articles were retained after screening. Of the wellbeing outcomes studied, QoL, functioning, and posttraumatic growth were well-researched. Across intervention types (CBT-based, third wave, and complementary), some interventions were efficacious for wellbeing outcomes (mainly QoL), but many had negligible or nonsignificant effects. Other than social support, external resources, and systemic supports were understudied. Intensive interventions and those involving daily practice most effectively promoted wellbeing. Protective factors such as social support, executive functioning, optimism, and system-level resources should be better incorporated into PTSD care for service members/veterans.