BACKGROUND: As cognitive, emotional, and health-related behavioral issues are prevalent among persons with multiple sclerosis (MS), mental health services are a valuable component of comprehensive care. However, it is unknown how many participate in neuropsychological and psychotherapeutic services, and whether the presence of certain co-occurring conditions increase service use. This study aimed to examine the frequency and associated factors (e.g., age, gender, education, race/ethnicity, and co-occurring conditions) of neuropsychological and psychotherapeutic service utilization in the Veterans Health Administration (VHA) among Veterans with MS. METHODS: Data were extracted from VHA Corporate Data Warehouse as part of the Women Veterans Cohort Study (WVCS), a longitudinal project with Veterans who served during the Iraq and Afghanistan conflicts. Participants (n = 1,686) were Veterans from the overall WVCS dataset who had three or more VHA MS-related encounters (inpatient, outpatient, and/or disease modifying therapy) within one calendar year between fiscal years 2010 and 2015. Neuropsychological assessment participation was identified by procedural codes 96118 and 96119, while psychotherapeutic services were defined using 90804, 90806, 90808, 96150, 96151, and 96152. Bivariate analyses were conducted to identify socio-demographics and clinical characteristics that differed between Veterans who did and did not use these services. Service dates were compared to the diagnosis dates of the co-occurring conditions to determine whether the majority of the diagnoses preceded the service (e.g., a recognized problem) or were coded the day of or after the initial appointment (e.g., a suspected problem), which informed what co-occurring conditions and participants were included in the subsequent logistic regressions. RESULTS: Two hundred eighty-one Veterans (16.67%) participated in a neuropsychological assessment. Veterans who had an evaluation had higher rates of several co-occurring conditions (ps < 0.01), though no significant relationships emerged with any of the socio-demographic variables and participation. After controlling for age, gender, education, and race/ethnicity, two previously diagnosed co-occurring conditions predicted service utilization: traumatic brain injuries (TBIs; OR: 2.33, 95% CI: 1.60, 3.35) and mood disorders (i.e., depressive and bipolar disorders; OR: 1.71, 95% CI: 1.26, 2.31). Psychotherapeutic service usage was more common, occurring in over 45% (n = 771) of the sample. Service utilization was associated with several co-occurring conditions (ps < 0.001), as well as level of education (p = .003). Focusing on participants who were diagnosed the day of or after the initial encounter, five co-occurring conditions were predictors of psychotherapeutic service use: mood disorders (OR: 1.81, 95% CI: 1.34, 2.46), anxiety disorders (OR: 1.38, 95% CI: 1.03, 1.85), sleep disorders (OR: 1.55, 95% CI: 1.19, 2.01), alcohol-related disorders (OR: 3.29, 95% CI: 1.79, 6.21), and cognitive disorders (OR: 3.72, 95% CI: 2.29, 6.16). CONCLUSIONS: These findings suggest that these services are being utilized by clinicians and Veterans to address the clinical complexity related to having MS and one or more of these other conditions.