Aim: Gaucher disease (GD) is a rare autosomal recessive condition. Type 1 GD (GD1) is the most prevalent form of GD in Western countries; enzyme replacement therapy (ERT) is a treatment option for patients with GD1. To understand the economic value of the GD1 ERT velaglucerase alfa, a budget impact model (BIM) was developed from a United States (US) payer perspective., Methods: We estimated the budget impact of velaglucerase alfa for a 10-million-member US health plan by comparing the annual total costs of therapy between a scenario using current velaglucerase alfa uptake to a projected scenario with increased velaglucerase alfa uptake. Total drug costs for both scenarios were estimated as the sum of the product of the number of eligible patients on each treatment and the annual per-patient cost of each medication. Average per-patient costs for ERTs were calculated by adding the yearly drug acquisition, drug administration, and site-of-care markup costs. The budget impact was measured over years 1-3., Results: An estimated 65 patients would receive velaglucerase alfa treatment in year 1, increasing to 90 patients by year 3. Across analyses, cost savings were realized with velaglucerase alfa compared with imiglucerase ($115,909) and taliglucerase alfa ($80,401). An annual total budget savings of $8.67 million could be realized for a hypothetical 10-million-member US health plan with increased velaglucerase alfa uptake. The per-member per-month costs decreased by $0.0241 across years 1-3., Conclusions: BIM results show that increased velaglucerase alfa uptake for GD1 treatment is cost-saving for US health plans.