Aim While autonomic imbalance during defecation/micturition can cause hemodynamic instability, stroke occurring in the toilet has rarely been investigated. The objective of the present study was to clarify the frequency and clinical characteristics of toilet‐related stroke. Methods Clinical data prospectively acquired between January 2011 and December 2015 on 1939 patients with acute stroke (1224 cerebral infarctions [CI], 505 intracerebral hemorrhages [ICH] and 210 subarachnoid hemorrhages [SAH]) were reviewed to identify patients with a toilet‐related stroke. For each stroke type, the ratios of stroke occurring during defecation/micturition to those occurring during other activities were calculated. Subsequently, how patients with toilet‐related stroke were brought to medical attention was investigated. Whether older patients (aged >65 years) had an elevated ratio of toilet‐related stroke was investigated in each stroke type. Results A total of 108 patients (41 CI, 37 ICH and 30 subarachnoid hemorrhages) sustained a stroke in the toilet. The ratio of toilet‐related stroke was highest in subarachnoid hemorrhages (14.3%), followed by ICH (7.3%). Circadian differences existed among the three stroke types: toilet‐related CI were more likely to occur in the night‐time than ICH. Patients with toilet‐related CI were significantly more likely to sustain cardioembolic stroke. In all three stroke types, <40% of patients could call for help by themselves. Older patients showed a significantly higher proportion of toilet‐related stroke in CI, but not in hemorrhagic strokes. Conclusions The toilet is a closed space where stroke occurs disproportionately frequently. Effort to reduce the incidence of toilet‐related strokes is warranted, as early patient detection is not always feasible. Geriatr Gerontol Int 2017; ••: ••–••.