Background: Spinal muscular atrophy (SMA) is a rare genetic neuromuscular disease. Objective: Characterize direct costs associated with SMA management. Data source: Truven Health Analytics MarketScan claims data (2012-2016). Patients: Eligible patients had ≥2 SMA-related medical claims ≥30 days apart. Patients were matched (1:1) to controls by birth year, gender, and geographic region. Patients were categorized as having infantile, child, or juvenile SMA based on diagnosis at age <1, 1-3, or 3-18 years, respectively. Main outcome measures: Annual inpatient and outpatient insurance claims and costs (2019 USD) for cases versus controls. Results: Fifty-eight, 56, and 279 cases and controls comprised the infantile, child, and juvenile cohorts, respectively. Cases had more inpatient claims than controls (infantile: 60.3% vs 1.7%; child: 35.7% vs 3.6%; juvenile: 47.0% vs 4.3%; all P ≤ 0.002). Mean net payments for inpatient admissions were higher for cases versus controls