Abstract: Objective: To examine the degree of discrepancy between Test of Premorbid Functioning (TOPF) predicted and actual WAIS-IV FSIQ between monolingual English-speaking veterans (MV) and bilingual English/Spanish-speaking veterans (BV). Method: Data from neuropsychological evaluation of 97 clinically referred veterans (Mage = 53.02, SD = 14.24, range = 23–80; Medu = 13.87, SD = 2.86, range = 6–20; 81 MV, 16 BV) were included. The percentage of male Participants was 80.4. Inclusion criteria were completion of the TOPF and the full standard Wechsler Adult Intelligence Scale – Fourth Edition (WAIS-IV). Exclusion criteria were PVT failure, neurocognitive disorder, learning disability, substance use disorders, and psychotic disorders. Mean TOPF-predicted FSIQ (combined demographic + TOPF) and mean WAIS-IV FSIQ were computed for each group, as well as mean discrepancy between observed and predicted FSIQ (DISo-p). Results: MV and BV differed in mean WAIS-IV FSIQ (t = 3.20, p = .0002) and mean TOPF-predicted FSIQ (t = 2.09, p = .039). Mean DISo-p was −1.88 for MV and −5.75 for BV. Mean DISo-p did not differ significantly between monolingual and bilingual groups (t = 1.71, p = .090). Conclusions: In a veteran sample, the TOPF combined prediction model functioned similarly for MV and BV without cognitive impairment. This provides preliminary support for the use of this measure to predict premorbid intellectual functioning among English/Spanish bilingual veterans. Additional research is needed to examine impact of English proficiency, age of acquisition, and education level on FSIQ prediction among bilingual veterans and in the population at large.