Can an independent laboratory bill both non-referred (i.e., self-reported) and referred services on the same electronic claim?

Yes. When a billing laboratory performs some laboratory tests and some testing is referred to another laboratory, the electronic claim does not have to be split.

  • The CLIA numbers from both the billing and reference labs must be submitted on the claim
    • Report the billing laboratory's CLIA number in loop 2300, REF02. REF01 = X4
    • Report the referral laboratory's CLIA number at the appropriate claim line level in loop 2400, REF02. REF01 = F4
  • CPT modifier 90 must be used on the line item tests performed by the reference laboratory
  • The performing (reference) laboratory's name, address and NPI must be entered in the appropriate facility provider loop for line items billed with CPT modifier 90

NOTE: When the reference laboratory is not located in the same billing jurisdiction as the referring laboratory, the referring (billing) laboratory must report their own NPI with the name, address, and ZIP Code of the performing provider in the appropriate data field for reporting purposes. The billing provider should keep a record of the performing provider’s NPI in the clinical records for auditing purposes.

Resource: IOM 100-04, Chapter 16, Sections (PDF, 569 KB)

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