A large body of research suggests that stress can affect how the immune system responds to vaccines. The impact of mental health disorders on humoral antibody response following immunization is not well understood, particularly for the COVID-19 vaccines. Leveraging a population-based longitudinal cohort assessing SARS-CoV-2 incidence in central North Carolina, we sought to investigate the relationship between mental health and immune response to vaccination. The 106 participants responded to biweekly surveys and contributed monthly serum samples that underwent SARS-CoV-2 spike antibody testing via enzyme-linked immunosorbent assay (ELISA). Utilizing weighted generalized linear models, we measured the association between depressive symptoms as recorded on the CESD-20 and quantitative antibody levels after COVID-19. Overall, we found modest differences in post-vaccination IgG between participants with depression and those without. Individuals with depressive symptoms had smaller initial antibody responses after vaccination (mean difference = -3.55, 95% CI = (-12.01, 4.90)). These results suggest that mental health disorders may affect immune response to vaccination.