MedicaidBilling CodesHigh impact
ICD-10 Implementation and Conversion
Illinois Medicaid - HFS·IL·Provider Notice
Effective date
Oct 1, 2014
We identified it
Jun 20, 2026
Summary
Illinois Medicaid will transition from ICD-9 to ICD-10 diagnosis and procedure codes effective October 1, 2014. Claims must use ICD-9 codes for services before October 1, 2014, and ICD-10 codes for services on or after that date.
Action Required
By October 1, 2014: Billing team must update all systems to use ICD-10-CM diagnosis codes and ICD-10-PCS procedure codes for all Illinois Medicaid claims with service dates on or after October 1, 2014. Continue using ICD-9 codes only for service dates before October 1, 2014. Train all coding staff on ICD-10 code selection. Claims submitted with incorrect code sets for the service date will be rejected.