Aims This observational cross-sectional study aimed to answer the following questions: 1) how has nonunion incidence developed from 2009 to 2019 in a nationwide cohort; 2) what is the age and sex distribution of nonunions for distinct anatomical nonunion localizations; and 3) how high were the costs for surgical nonunion treatment in a level 1 trauma centre in Germany? Methods Data consisting of annual International Classification of Diseases (ICD)- 10 diagnosis codes from German medical institutions from 2009 to 2019, provided by the Federal Statistical Office of Germany (Destatis), were analyzed. Nonunion incidence was calculated for anatom-ical localization, sex, and age groups. Incidence rate ratios (IRRs) were determined and com-pared with a two-sample z -test. Diagnosis-related group (DRG)-reimbursement and length of hospital stay were retrospectively retrieved for each anatomical localization, considering 210 patients. Results In 2019, a total of 11,840 nonunion cases (17.4/100,000 inhabitants) were treated. In com-parison to 2018, the incidence of nonunion increased by 3% (IRR 1.03, 95% confidence in-terval (CI) 0.53 to 1.99, p = 0.935). The incidence was higher for male cases (IRR female/ male: 0.79, 95% CI 0.76 to 0.82, p = 0.484). Most nonunions occurred at the pelvic and hip region (3.6/100,000 inhabitants, 95% CI 3.5 to 3.8), followed by the ankle and foot as well as the hand (2.9/100,000 inhabitants each). Mean estimated DRG reimbursement for in-hospital treatment of nonunions was highest for nonunions at the pelvic and hip region ( euro 8,319 (SD 2,410), p < 0.001). Conclusion Despite attempts to improve fracture treatment in recent years, nonunions remain a problem for orthopaedic and trauma surgery, with a stable incidence throughout the last decade.