Antibiotic prescribing can lead to adverse drug events and antibiotic resistance, which pose ongoing urgent public health threats (1). Adults aged ≥65 years (older adults) are recipients of the highest rates of outpatient antibiotic prescribing and are at increased risk for antibiotic-related adverse events, including Clostridioides difficile and antibiotic-resistant infections and related deaths (1). Variation in antibiotic prescribing quality is primarily driven by prescribing patterns of individual health care providers, independent of patients' underlying comorbidities and diagnoses (2). Engaging higher-volume prescribers (the top 10% of prescribers by antibiotic volume) in antibiotic stewardship interventions, such as peer comparison audit and feedback in which health care providers receive data on their prescribing performance compared with that of other health care providers, has been effective in reducing antibiotic prescribing in outpatient settings and can be implemented on a large scale (3-5). This study analyzed data from the Centers for Medicare & Medicaid Services (CMS) Part D Prescriber Public Use Files (PUFs)* to describe higher-volume antibiotic prescribers in outpatient settings compared with lower-volume prescribers (the lower 90% of prescribers by antibiotic volume). Among the 59.4 million antibiotic prescriptions during 2019, 41% (24.4 million) were prescribed by the top 10% of prescribers (69,835). The antibiotic prescribing rate of these higher-volume prescribers (680 prescriptions per 1,000 beneficiaries) was 60% higher than that of lower-volume prescribers (426 prescriptions per 1,000 beneficiaries). Identifying health care providers responsible for a higher volume of antibiotic prescribing could provide a basis for additional assessment of appropriateness and outreach. Public health organizations and health care systems can use publicly available data to guide focused interventions to optimize antibiotic prescribing to limit the emergence of antibiotic resistance and improve patient outcomes.