Electroconvulsive therapy (ECT) is a highly efficacious treatment for severe depression. However, a disadvantage of ECT is the risk of cognitive side effects. Magnetic seizure therapy (MST) is a novel treatment modality, by which therapeutic seizures are induced using rapidly alternating strong magnetic fields. In this case study, we report on successful MST treatment of an episode of otherwise treatment-resistant depression in a patient with bipolar I disorder. Compared with published ECT results, MST seizures in this case report were of shorter duration, lower ictal electroencephalogram amplitude, and less pronounced postictal suppression. Furthermore, the patient did not experience subjective side effects and particularly recovered time to full orientation more quickly with MST than what has been previously described for ECT. Taken together, these results suggest that MST, compared with ECT, might have antidepressant effects and may have fewer clinical side effects.