This analysis reported continually decreasing Medicare reimbursement for both radiation and medical oncology from 2010-2020 and 2016-2020. Chemotherapy (-40%) and radiotherapy (-33%) saw the largest decreases in inflation- and utilization-adjusted reimbursement from 2010-2020, while immunotherapy (+21%) saw the largest increase. From 2010-2020, Medicare reimbursement decreased by $1.2B (-16%) for all codes, $705M (-29%) for radiation oncology-specific codes, and $541M (-10%) for medical oncology-specific codes.