Traumatic brain injury (TBI) is a global health concern, that can leave lasting physical, cognitive, and/or behavioral changes for many who sustain this type of injury. Because of the heterogeneity of this population, development of appropriate intervention tools can be difficult. Social determinants of health (SDoH) are factors that may impact TBI incidence, recovery, and outcome. The purpose of this study is to describe and analyze the existing literature regarding the prevailing SDoH and health disparities (HDs) associated with TBI in adults. A scoping review, guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework was used to explore three electronic databases—PubMed, Medline, and CINAHL. Searches identified peer-reviewed empirical literature addressing aspects of SDoH and HDs related to TBI. A total of 123 records were identified and reduced to 27 studies based on inclusion criteria. Results revealed race/ethnicity was the most commonly reported SDoH impacting TBI, followed by an individual’s insurance status. Health disparities were noted to occur across the continuum of TBI, including TBI risk, acute hospitalization, rehabilitation, and recovery. The most frequently reported HD was that Whites are more likely to be discharged to inpatient rehabilitation compared to racial/ethnic minorities. Health disparities associated with TBI are most commonly associated with the race/ethnicity SDoH, though insurance status and socioeconomic status commonly influence health inequities as well. The additional need for evidence related to the impact of other, lesser researched, SDoH is discussed, as well as clinical implications that can be used to target intervention for at-risk groups using an individual’s known SDoH.