In this article, we used administrative claims data from the OptumLabs Data Warehouse and American Hospital Association Annual Survey data to examine associations between hospital characteristics and uptake of biosimilar granulocyte colony-stimulating factor treatments. We found that 340B-participating hospitals and non-rural referral center (RRC) hospitals that reported owning rural health clinics were less likely to administer the lower-cost biosimilars, whereas the opposite was true for hospitals that are RRCs. To our knowledge, our study offers a first look at an underappreciated source of disparities in access to lower-cost medications such as biosimilars. Results from our study reveal opportunities for targeted policies to encourage adoption of lower-cost treatments, particularly among hospitals that serve rural communities where patients often have fewer choices in care site.