The treatment of complex radial head fractures remains controversial with open reduction and internal fixation (ORIF), radial head arthroplasty, and radial head excision being the most common treatment options. While ORIF is the preferred treatment strategy for Mason type II fractures, the optimal treatment of Mason type III fractures is debated. To report minimum 10-year outcomes after ORIF of Mason type II and type III radial head fractures. We hypothesized that both Mason Type II and Type III fracture patients would demonstrate satisfactory clinical outcomes at minimum 10-year follow-up. All patients with Mason type II or III radial head fractures who were treated with ORIF by a single surgeon between 2005 and 2010 were included. Fractures with significant bone defects were treated with bone grafts and elbow ligament injuries were treated with either primary ligament repair or reconstruction. Patient reported outcome (PRO) questionnaires were administered at the time of last clinical follow-up and at a minimum of 10 years postoperatively. Twenty-four patients, including 13 male and 11 female patients with an average age of 39 (range 19-60) at the time of surgery met inclusion criteria. Thirteen patients suffered from Mason type II and 11 patients from Mason type III fractures. At initial follow-up, 21 out of 24 fractures (88%) demonstrated radiographic union. Three non-unions, 2 of which were Mason type III fractures, were treated with revision ORIF and iliac crest bone grafting. 11 patients developed postoperative elbow stiffness and required capsular release surgery. At last clinical follow-up, average flexion was 139 degrees, average extension was 4 degrees, average supination was 77 degrees, and average pronation was 81 degrees. The median DASH score was 7 (ranging from 0 - 32). Minimum 10-year follow-up (mean: 14.6 years) was collected on 18 of 24 (75%) of the patients. At a minimum of 10 years postoperatively, the median QuickDASH score was 4.5 (range: 0 to 25) and the median SANE score was 96.5 (range: 75-100). Median satisfaction with the surgical outcome was 10/10 (range: 3-10). ORIF of Mason type II and III radial head fractures results in high union rates with good functional outcomes at a mean of 14.6 years postoperatively. The study results suggest that ORIF of Mason type II and III radial head fractures leads to long-term positive functional outcomes.