MedicaidBilling CodesHigh impact
Applied Behavior Analysis (ABA) Billing
Missouri Medicaid (MO HealthNet)·MO · Psychiatry·Provider Notice
Effective date
Oct 13, 2022
We identified it
Jun 20, 2026
Summary
Applied Behavior Analysis (ABA) billing now requires specific modifiers based on provider type: HO for behavior analysts/psychologists, HN for assistant behavior analysts, and HM for RBTs with supervisor modifiers. The U8 modifier is required for home/other locations except for RBT services.
Action Required
Immediately: Billing team must update system to require modifier HO for behavior analysts and psychologists billing ABA services, modifier HN for assistant behavior analysts, and modifier HM for RBTs along with appropriate supervisor modifier (HO or HN). Add U8 modifier requirement for Place of Service 12 (home) or 99 (other) except for RBT services. Remove AH modifier from psychologist ABA billing. Update encounter forms and train staff on new modifier requirements.