To (a) characterize a sample of post-9/11 caregivers providing help to service members and veterans (SMV) following traumatic brain injury (TBI), (b) examine the level of support provided, and (c) determine caregiver health and well-being outcomes.Military treatment facility.Caregivers (N = 278) of SMVs who sustained a mild, moderate, severe, or penetrating TBI (96.0% female; 86.0% spouse/partner; age: M = 38.7 years, SD = 10.4). Participants were divided into 3 groups on the basis of the level of support provided (low, medium, high).Prospective observational.Caregiver Appraisal Scale, SF-36v2 Health Survey, Mayo-Portland Adaptability Inventory-4, Caregiver Questionnaire.The majority of caregivers were helping an SMV with mild TBI and comorbid posttraumatic stress disorder/depression, who was injured in a blast-related incident during combat. Caregivers helped predominantly with activities of daily living and/or instrumental activities of daily living and spent more than 40 hours per week providing care. High-support caregivers were more likely to be caring for an SMV with comorbid posttraumatic stress disorder, report poor physical and mental health outcomes, and have a negative impact on employment and finances.A better understanding of protective factors is required to ensure that burden of care does not exceed the caregiver's health and financial capacity, or undermine the care, well-being, and recovery of the SMV.