MedicaidAdministrativeHigh impact
Improper Submission of the CMS 1500, Health Insurance Claim Form
Illinois Medicaid - HFS·IL·Provider Notice
Effective date
Oct 5, 2018
We identified it
Jun 20, 2026
Summary
Illinois Medicaid providers must stop submitting CMS 1500 forms for fee-for-service Medicaid claims. Only HFS proprietary paper forms are accepted, with different forms required for different provider types and services.
Action Required
Immediately: Illinois providers billing fee-for-service Medicaid must stop using CMS 1500 forms and switch to appropriate HFS proprietary forms (HFS 215, 1443, 2209, 2210, 2211, 2212, 2360, or 3797) based on provider type and service. Billing team should order correct forms from the Department's website and update billing workflows. HFS strongly recommends switching to electronic billing through MEDI IEC System. Claims submitted on CMS 1500 forms will not be processed and cannot be tracked.