Modifier 90 — Reference (Outside) Laboratory billing
This payment policy governs billing and reimbursement for laboratory tests appended with modifier 90 (Reference/Outside Laboratory) across Premera Blue Cross lines of business; it affects all providers and facilities submitting professional or facility claims to the plan.
Only one laboratory may bill for a referred laboratory service.
Policy clarified to apply to facility claims and to clarify correct use of modifier 90 with effective claim dates on or after December 11, 2023 for facility claims.
Created 'Codes and Coding Guidelines' section identifying drawing fee procedure code(s) (e.g., 36415) as not valid with modifier 90.
Modifier 90 Coverage Criteria
Modifier 90 coverage criteria
Covered when ALL of the following are met:
ALL of the following
- The independent reference laboratory that analyzed the laboratory test must bill the Plan directly and append modifier 90.
- Only one laboratory may bill for a referred laboratory service.
- The Plan does not reimburse laboratory tests appended with modifier 90 when billed by a party other than the independent reference laboratory that analyzed the test (applies to professional and facility claims).
- Modifier 90 is not valid on drawing fee procedure codes such as 36415.
Codes and Coding Guidelines
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