ImportanceVaccines against SARS-CoV-2 are highly effective in the general population; however, their efficacy may be diminished in maintenance dialysis patients, a population particularly vulnerable to COVID-19 infection and morbidity.ObjectiveWe assessed vaccine response in a national sample of maintenance dialysis patients and identified predictors of response.DesignRetrospective cohort studySetting130 Dialysis Clinic, Inc (DCI) facilitiesParticipantsMaintenance dialysis patients without known prior COVID-19 or a positive baseline antibody titerExposure(s)Vaccine type and clinical characteristicsMain Outcome(s)Using a semi-quantitative assay for antibodies against SARS-CoV-2 spike antigen, vaccine response was defined as at least one titer ≥1 U/L between 14 and 74 days after completion of a SARS-CoV-2 vaccine series. Regression analysis was used to identify characteristics associated with response.ResultsAmong 1528 patients, 437 received BNT162b2/Pfizer vaccine, 766 received mRNA-1273/Moderna, and 325 received Ad26.COV2.S/Janssen. Serologic response differed significantly by vaccine type: 381/437 (87%) among BNT162b2/Pfizer recipients, 736/766 (96%) among mRNA-1273/Moderna recipients, and 119/325 (37%) among Ad26.COV2.S/Janssen recipients. Vaccine type, older age, immune-modulating medication, history of transplantation, and lower serum albumin were associated with vaccine non-response.Conclusions and RelevanceSerologic response to mRNA vaccines is robust among maintenance dialysis patients. Future research should evaluate durability of this response, correlation between seroresponse and protection from COVID-19, and the role of the AD26.COV2.S/Janssen vaccine in this vulnerable population.