Background. During tuberculosis treatment, patients may transfer to continue treatment at another health facility. To ensure adherence until treatment completion, keeping track of patients is paramount. This study aimed to investigate treatment outcomes of patients who transferred out from the University of Gondar Hospital. Methods. This was a retrospective cohort evaluation of patients registered from 2009 to 2013. Treatment outcomes were collected from the TB registers of receiving units using a standardized data capture format. Results. During the study period 3,707 patients initiated treatment and 47.5% (1,760) transferred out. The study evaluated the outcome of 26% (457/1,760) patients, of whom 403 (88%) arrived in the receiving units. Overall, 79% were successfully treated and 13.8% transferred out for a second time. For all transferred-out cases, treatment outcomes were not reported to the referring unit. Conclusion and Recommendation. About half of the patients were transferred out to complete treatment elsewhere. Although successful treatment outcome was obtained in 79% of patients, these results were not fed back to the referring unit. Implementing a clear mechanism to communicate the arrival of and treatment outcome for transfer-out patients and appropriate patient education on treatment unit selection before treatment and during transfer-out are recommended.