MedicaidBilling CodesMedium impact
UPDATE: New Sections Published under the Comprehensive Billing Guide for Medicaid Managed Care Services
Illinois Medicaid - HFS·IL · Psychiatry, Family Medicine, General Practice +1 more·Provider Notice
Effective date
Feb 1, 2023
We identified it
Jun 20, 2026
Summary
Illinois Medicaid MCOs have published versions 26 and 27 of their Comprehensive Billing Guide with updates to behavioral health services, vision providers, long-term care billing, and new diabetes prevention programs. Key changes include procedure code T1040 modifications for FQHCs/RHCs effective February 1, 2023, and new Pathways to Success program billing guidance.
Action Required
Immediately: Illinois providers contracted with Medicaid MCOs should review the updated Comprehensive Billing Guide versions 26 and 27 at https://iamhp.net/providers. FQHCs, RHCs, and ERCs must update billing systems to use the modified procedure code T1040 for behavioral health encounters with dates of service February 1, 2023 and later. Update encounter forms and staff training for new Pathways to Success program billing requirements effective January 1, 2023.