A Canada-wide warrant was issued for Charles Albert Hansen, 60, after he failed to return from day leave at Colony Farm on Friday morning.
Hospital staff says Hansen returned himself late Friday night.
An investigation into Hansen's disappearance will be made as standard review policy.
Neighbours have raised concerns about security at the hospital. In the last three years, 42 patients have failed to return on time while on day leave, and four attempted to escape. One patient is still at large after failing to return from a day pass in May.