The rate of nonunion is estimated to be 1.1% to 10% following closed treatment of proximal humerus fracture and 5.5% following closed treatment of humeral shaft fracture. Surgical management should be considered for fractures that demonstrate no evidence of progressive healing on consecutive radiographs taken at least 6 to 8 weeks apart during the course of closed treatment. In the case of proximal humerus nonunion, recent series have demonstrated union in >90% of patients treated with reconstruction using locking plates and autogenous bone graft. Shoulder arthroplasty is reserved as a salvage option in cases in which the humeral head is not viable or the proximal fragment will not support osteosynthesis. For humeral shaft nonunions, open reduction and internal fixation with compression plating and bone graft remains the standard of care, with a >90% rate of union and good functional outcomes. Recent studies support the use of locked compression plates, dual plating, and cortical allograft struts in patients with osteopenic bone.