MedicaidBilling CodesMedium impact
Clarification Regarding Use of Modifier 90 [Reference (Outside) Laboratory] for Hospital Outpatient Claims Billed on the 837P or HFS 2360 Claim Formats
Illinois Medicaid - HFS·IL · Pathology·Provider Notice
Effective date
Jun 1, 2018
We identified it
Jun 20, 2026
Summary
Illinois hospitals billing outpatient laboratory services on 837P or HFS 2360 claim formats must now use modifier 90 when reference laboratories complete the service for HealthChoice Illinois MCO and traditional fee-for-service Medicaid patients. This requirement does not apply to Medicare crossover claims or institutional UB-04/837I claim formats.
Action Required
By June 1, 2018: Illinois hospital billing teams must update systems to append modifier 90 to non-Ambulatory Procedures Listing lab services billed on 837P or HFS 2360 formats when reference laboratories complete the global service for HealthChoice Illinois MCO and traditional Medicaid patients. Do not use modifier 90 for Medicare crossover claims or when hospital completes testing in-house. Update billing software rules and staff training accordingly.