BackgroundAlopecia areata is a T‐cell mediated autoimmune disease that occurs in humans and various other mammalian species. When the disease progresses to total alopecia it is defined as alopecia areata universalis (AAU), although this outcome has only been described in humans.Hypothesis/objectivesTo describe a case of canine alopecia areata universalis and its clinical outcome after 22 months of follow‐up.AnimalA 9‐year‐old intact male cross‐breed hunting dog was presented with generalized and complete noninflammatory alopecia of 12–14 months duration.MethodsClinical examination; histopathological and immunohistochemical examination of skin biopsies.ResultsThere was loss of all body hair including eyelashes and vibrissae. The histopathological and immunohistochemical findings supported a diagnosis of long‐standing alopecia areata. Treatment with oral ciclosporin was associated with hair regrowth but muzzle hair, most eyelashes and whiskers were still lacking after 17 months of therapy.Conclusions and clinical importanceTo the best of the author's knowledge this is the first documented case of canine AAU. The clinical and histopathological features were consistent with a diagnosis of AAU as defined in humans. Treatment with oral ciclosporin resulted in near complete resolution of the alopecia, but after 5 months without treatment the alopecia did not relapse and spontaneous resolution cannot be ruled out.