Etomidate and methohexital are the 2 commonly used anesthetics for electroconvulsive therapy (ECT) in the United States. The objective of this study was to examine how anesthetic choice between etomidate and methohexital is associated with real-world clinical outcomes. This naturalistic retrospective cohort study examined longitudinal electronic health records for 495 adult patients who received 2 or more ECT treatments from 2010 to 2019 in Kaiser Permanente North California, a large integrated health care system. Study outcomes included 12-month posttreatment depression remission as measured by the 9-item Patient Health Questionnaire, psychiatric and all-cause emergency department visits, and psychiatric and all-cause hospitalizations. Anesthetic choice was not significantly related to depression severity, emergency department visits, or psychiatric hospitalizations at 12 months after completing ECT. In exploratory analyses, we found that etomidate compared with methohexital was associated with higher rates of patient discomfort adverse effects-postictal agitation, phlebitis, and myoclonus (2.4% vs 0.4%; P < 0.001). We present the first large comparison of etomidate and methohexital as anesthetics for ECT and their associations with real-world outcomes. Our study showed no significant difference on depression remission, emergency department visits, or hospitalizations 12-months posttreatment. Thus, clinicians should focus on other patient or treatment characteristics when deciding on anesthetics for ECT. Further investigation is needed to confirm our exploratory findings that etomidate use was correlated with a higher rate of patient discomfort adverse effects relative to methohexital.