Transgender and gender-diverse (TGD) individuals experience higher rates of mood and anxiety disorders than the general public. Transcranial direct current stimulation (tDCS) is an effective and well-tolerated treatment for major depressive disorder, in cisgender patients. With the very recent exception of electroconvulsive therapy (ECT), neuromodulation in TGD patients is not addressed in the literature. We described here the efficacy and tolerability of tDCS in a 22-year-old Caucasian female-to-male transgender individual (hereafter referred to as a male) suffering from a severe non-treatment-resistant major depressive disorder. This case report suggests that combined tDCS and antidepressant therapy have the potential to treat depressive disorders in patients of all gender identities.