A 10‐year‐old, female, neutered, domestic shorthair cat was referred for evaluation of lethargy and pyrexia, unresponsive to treatment with meloxicam, potentiated amoxicillin and marbofloxacin. Radiographs of the elbows and tarsi revealed marked periosteal reaction and joint effusion. Arthrocentesis was consistent with a suppurative polyarthritis. Hepatozoonosis was suspected following identification of a Hepatozoon gametocyte, during buffy coat assessment. Diagnosis was confirmed with a positive Hepatozoon felis polymerase chain reaction on a whole blood sample. The cat received a 4‐week course of oral doxycycline, which resulted in normalisation of body temperature, lameness and demeanour. Almost 18 months following diagnosis and treatment, the patient is clinically normal. This case shows that hepatozoonosis should be considered as a differential in cats with a history of foreign travel presenting with polyarthritis.