MedicaidBilling CodesMedium impact
Pharmacy Influenza Vaccine Administration Fee - Billing Instructions Update
Illinois Medicaid - HFS·IL · Pharmacy·Provider Notice
Effective date
Mar 26, 2017
We identified it
Jun 20, 2026
Summary
For Illinois Medicaid pharmacy claims, influenza vaccine administration fees must now be billed using the B1 transaction instead of the S1 transaction, with the administration fee entered in the Incentive Amount Submitted field (438-E3) and 'MA' in the Professional Service Code field (440-E5). The maximum administration fee allowed is $6.40.
Action Required
Immediately: Pharmacy billing teams in Illinois must update Medicaid billing procedures for influenza vaccines to use B1 transaction instead of S1. Enter administration fee amount in field 438-E3 (maximum $6.40) and enter 'MA' in field 440-E5. Claims will reject if these fields are populated incorrectly or if administration fee exceeds $6.40.