Background: Early integration of palliative care is recommended for patients with newly diagnosed advanced cancer. However, many patients with cancer only receive this essential care during hospitalization or at the end of life, likely resulting in poor symptom management and increased morbidity, suffering, and financial burden for patients and families. This study aimed to examine disparities in geographical access to palliative care in the US. Methods: The study utilized data from the 2018-2019 National Cancer Database (NCDB) and CMS Medicare Physician and Other Practitioners dataset. Included patients were newly diagnosed with stage 4 cancer with geographic information for patients’ residential and their treating facilities’ zip codes. We geocoded the addresses of practices where physicians provided palliative care services 2018 -2019. The OpenStreetMap and Open Source Routing Machine (OSRM) model was employed to estimate the travel distance between patients' residences and the nearest palliative care clinician, as well as between their treating facilities and the nearest palliative care clinicians. Results: 335,191 stage 4 cancer patients and 1,063 clinicians who specialize in palliative care were included in the analysis. The most common cancer diagnoses were lung (28.8%), colorectal (10.2%), pancreatic (7.8%), and breast (4.9%) cancers. Distance to the nearest palliative care clinician was more than 12.5 miles for 63.4% of patients and 45.4% of treating facilities, and more than 50 miles for 24.1% of patients and 19.1% of treating facilities (Table). Patients who lived ≥50 miles away from the nearest palliative care clinic tended to be White, have a lower household income, and live in rural areas. Facilities located ≥50 miles away from the nearest palliative care clinics tended to be in rural areas and community or comprehensive community facilities. (all p<0.0001). Conclusions: 63.4% and 24.1% patients with newly diagnosed stage 4 cancers lived at least 12.5 miles and 50 miles from their nearest palliative care clinicians. Geographic disparities in palliative care availability underscore the need for policy and practice interventions aimed at improving equitable access to palliative care for patients with advanced cancer.