ASTRO has issued a letter to all 50 state Medicaid Directors requesting updates to radiation treatment delivery codes that took effect on January 1, 2026. ASTRO members have reported that many Medicaid programs have not yet revised their billing systems or fee schedules to align with these changes. ASTRO is urging Medicaid programs to promptly update their systems to reflect the new coding structure. Please visit our Payer Support and Resolution Center for updated guidance or to report a wrongful denial.