Prader-Willi Syndrome (PWS) is a multi-system genetic disorder characterized by hyperphagia and a range of medical complications. While register and cohort studies have explored the natural course of the syndrome, there is little nationallyrepresentative data. In this study the National Inpatient Sample, a de-identified allpayors database of acute care hospital discharges in the United States, was queried for patients discharged with a diagnosis of PWS in 2019. Hospitalizations involving PWS were compared to hospitalizations without a PWS diagnosis matched based on demographic and hospital factors. In total, 540 hospitalizations (95% CI: 513-567) included a diagnosis of PWS. Median age at time of admission was 22 years, with an interquartile range of 6.3-37.8 years. Respiratory conditions accounted for 110 (20.4%) of primary discharge diagnoses, with infectious conditions for 70 (13.0%) and digestive conditions for 65 (12.0%). Hospitalizations involving PWS were significantly more likely to involve respiratory failure (OR 5.49; 95% CI 3.86-7.80), septicemia (OR 2.80, 95% CI 1.97-3.96), or intestinal obstruction and ileus (OR 6.29; 95% CI 3.70-10.7) compared to matched hospitalizations without PWS.Obesity was diagnosed in 230 PWS hospitalizations (42.6%; OR 3.86, 95% CI 3.17-4.72 relative to non-PWS hospitalizations). These results point to an ongoing need for the improved diagnosis and treatment of PWS complications, and highlight the importance of specific billing codes for rare diseases to enhance the collection of real world evidence.