MedicaidReimbursementMedium impact
Ambulance Quantities and Rate Adjustments
Illinois Medicaid - HFS·IL · Emergency Medicine·Provider Notice
Effective date
Jul 1, 2013
We identified it
Jun 20, 2026
Summary
Illinois Medicaid updated ambulance billing rates and identified systematic issues with mileage billing. The department is processing automatic adjustments for previously underpaid claims from July 2013 forward, while correcting overpayments on mileage code A0425.
Action Required
For Illinois Medicaid ambulance providers: 1) Round mileage to nearest whole number - do not use decimals on paper claims, 2) Ensure base rate is always quantity of one at service line level, 3) For electronic billing vendors, verify miles are reported in CR106 with DH qualifier and overridden at line level for base rate, 4) Monitor System Issues page for adjustment updates, 5) Use 837P void/re-bill process within 12 months for corrections to avoid timely filing issues.