Purpose: To compare the donor site complication rate and length of hospital stay following the harvest of bone from the iliac crest, calvarium, or mandibular ramus. Materials and Methods: Ninety-nine consecutively treated patients were included in this retrospective observational single-center study. Results: Iliac crest bone was harvested in 55 patients, calvarial bone in 26 patients, and mandibular ramus bone in 18 patients. Harvesting of mandibular ramus bone was associated with the lowest percentages of major complications (5.6%), minor complications (22.2%), and total complications (27.8%). Harvesting of iliac crest bone was related to the highest percentages of minor complications (56.4%) and total complications (63.6%), whereas harvesting of calvarial bone induced the highest percentage of major complications (19.2%). The length of the hospital stay was significantly influenced by the choice of donor site (P = .003) and age (P = .009); young patients with the mandibular ramus as the donor site had the shortest hospital stay. Conclusions: Harvesting of mandibular ramus bone was associated with the lowest percentage of complications and the shortest hospital stay. When the amount of bone to be obtained is deemed sufficient, mandibular ramus bone should be the first choice for the reconstruction of maxillofacial defects. Keywords: atrophy, bone graft, calvarium, complications, defects, donor site, iliac crest, mandible, mandibular ramus, maxilla, reconstruction