BACKGROUND: Proximal humerus fractures are among the most common presenting fractures to orthopedic surgeons in the USA. Hypoalbuminemia is accepted as a nutrition marker associated with post-operative complications following common orthopedic interventions. QUESTIONS/PURPOSES: Thus, the authors sought to (1) describe the national demographic trends of patients undergoing surgical fixation for proximal humerus fracture and (2) investigate the association between pre-operative hypoalbuminemia, a malnutrition marker, and post-operative complications within 1 year of surgical intervention. METHODS: The PearlDiver Humana Claims Database was queried to identify a nationally representative cohort of patients who underwent surgical intervention for proximal humerus fractures from 2008 to 2015. Demographic and comorbid characteristics were collected. Pearson's χ-squared analysis was used to compare rates of 90-day and 1-year outcomes between hypoalbuminemia (albumin ≤ 3.5 mg/dL) and control groups. Multivariate logistic regression was then used to determine the isolated effect that hypoalbuminemia had on post-operative outcomes. RESULTS: Of the 3337 patients identified, 919 (27.5%) had available serum albumin data. Seventy (7.6%) patients had hypoalbuminemia. Hypoalbuminemia was more likely to be associated with post-operative sepsis (7.1% vs. 1.5%, respectively) and pneumonia (15.7% vs. 4.6) compared with controls. Additionally, hypoalbuminemia was associated with increased 90-day rates of discharge to extended care (4.3% vs. 0.8), emergency room visits (38.6% vs. 21.7), and total cost ($24,051.96 ± 24,972.74 vs. $15,429.74 ± 24,492.30). CONCLUSION: Our study suggests hypoalbuminemia is associated with an increased risk of complications, specifically pneumonia and sepsis, and total health care costs in patients undergoing surgery for proximal humerus fractures. These findings provide insight for individualized patient care that will aid in evaluating the potential risk of surgical complications in an effort to improve outcomes and reduce costs.