CurrentUnitedHealthcarePolicy N/A

CLIA identification reporting for laboratory claims

Requirements for submitting Clinical Laboratory Improvement Amendments (CLIA) certificate identification and related claim-level information for laboratory services billed to UnitedHealthcare Medicare Advantage plans, applicable to providers submitting CMS-1500/837P claims.

Policy Summary

PayerUnitedHealthcare

PolicyCLIA identification reporting for laboratory claims

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionReport the CLIA certificate identification number on claims (CMS-1500 Field 23 or ANSI X12 837 REFO2 with qualifier X4/F4).

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

Field 23paper CMS-1500 field for CLIA ID

ANSI X12 837electronic claim reference segment

QW, 90modifiers referenced

~260klaboratories covered (approx.)

Coverage Criteria

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CLIA reporting and validation criteria

Reimbursement eligible when ALL of the following are met:

Submit a valid CLIA Certificate Identification number on the claim for each CLIA-covered laboratory test.

For paper claims, report the CLIA number in Field 23 of the CMS-1500; for electronic 837P claims, report the CLIA number in the Ref segment (REFO2) with qualifier X4 as applicable.

If testing is performed at a servicing location other than the billing location (referred testing), report the referral laboratory's CLIA number at the line level using REFO2 with qualifier F4.

Include modifier QW when reporting CLIA‑waived tests where applicable and follow other applicable modifier and billing guidelines for referred testing.

The submitted CLIA certificate information must validate to the service provided and the servicing provider demographics must be complete.

ALL of the following

Claims missing the CLIA ID, containing an invalid CLIA ID, or lacking complete servicing provider demographic information will be considered incomplete and may be rejected or denied.
Line edits will be applied and claim lines may be denied when the laboratory certification level does not support the billed service code.

Operational note: Submission must follow ANSI X12 837 Professional Claim REFO2 usage (REFO1=X4 for billing location or REFO2 with F4 for referral servicing location) as described in policy guidance.

Claim-level Coding and Certification

Claim-level CLIA reporting codes/qualifiersmixed

REFO2:X4	Billing laboratory CLIA ID (Loop 2300 or Loop 2400 REFO2 with REFO1=X4) for tests performed at billing location
REFO2:F4	Referral laboratory CLIA ID (Loop 2400 REFO2 with REFO1=F4) for tests performed at a servicing location other than billing location
Modifier QW	Indicates CLIA-waived test

inv-03: Certification match — claim line edits when lab certification level does not support the billed service code

Certification matchClaim line edits will be applied when the lab certification level does not support the billed service code.

ConsequenceClaims missing the CLIA ID, containing an invalid CLIA ID, or lacking complete servicing provider demographics may be rejected or denied.

ActionVerify that the CLIA certificate type held by the performing laboratory supports the specific test code before billing to avoid line edits.

Provider Billing Requirements and Actions

Denial Risk

Claim completeness and validation

A claim that does not contain the CLIA certificate identification number (CLIA ID), contains an invalid CLIA ID, or lacks complete servicing provider demographic information will be considered incomplete and may be rejected or denied. Line-level edits will also be applied when the laboratory's certification level does not support the billed service code. Providers must ensure the correct CLIA ID is reported in the required claim fields to avoid denials or rejections.

Missing or invalid CLIA ID or incomplete servicing provider demographics → claim may be rejected or denied
Line edits applied if lab certification level does not support billed service code

Billing Rule

CLIA ID claim reporting requirements

Report the CLIA certificate identification number on claims as follows to meet reporting requirements and avoid claim rejection: on paper CMS-1500 (Field 23) and on electronic ANSI X12 837 professional claims in the REF segment as REFO2 with REFO1 qualifier = "X4". For billing laboratory CLIA IDs, populate Loop 2300 REFO2 with REFO1=X4 (or Loop 2400 REFO2 with REFO1=X4 for specific CLIA-covered tests). For testing performed by a referral laboratory, report the referral laboratory's CLIA number in Loop 2400 REFO2 with REFO1=X4.

Paper CMS-1500: Field 23
Electronic ANSI X12 837P: REF segment — REFO2 with REFO1 qualifier = "X4" (Loop 2300 for billing lab or Loop 2400 for specific tests)
Referred testing: Loop 2400 REFO2 with REFO1 = "X4" for the referral/rendered laboratory

Definitions

inv-06: Laboratory — definition of a laboratory facility that examines human-derived materials

DefinitionA facility that examines materials derived from the human body to provide information for diagnosis, prevention, treatment, or assessment of health; CLIA applies if even one such test is performed.

Regulatory scopeCLIA regulatory requirements vary according to the kind of test(s) the laboratory conducts; entities meeting CLIA's laboratory definition must obtain an appropriate CLIA certificate prior to patient testing.

ScaleCLIA covers approximately 260,000 laboratory entities in total.

inv-07: CLIA Waived Test / Modifier QW — definition and modifier use

CLIA Waived Test / Modifier QWCLIA-waived tests are 'simple laboratory examinations and procedures that have an insignificant risk of an erroneous result.' When applicable, report these tests with modifier QW.

Modifier use on CMS-1500Inclusion of modifier QW on CMS-1500 claim forms is necessary to evaluate eligibility for benefit coverage of CLIA-waived laboratory services.

Claim-level qualifiers for referred vs billing labUse REFO2 with qualifier X4 to report the billing laboratory's CLIA ID and use REFO2 with qualifier F4 at the line level to report the referral (servicing) laboratory's CLIA ID when testing is performed at a different location.

inv-08: Referring vs Reference Laboratory — roles and appropriate claim line qualifiers

Referring laboratoryA Medicare-approved laboratory that receives a specimen and refers the specimen to another laboratory for performance of the test (submits the specimen to another lab).

Reference (servicing) laboratoryA Medicare-enrolled laboratory that receives a specimen from a referring laboratory and actually performs the test.

Claim line qualifiersApply appropriate claim line qualifiers to indicate which CLIA ID (billing or servicing) applies; REFO2:X4 for billing lab CLIA ID and REFO2:F4 for referral/servicing lab CLIA ID at loop 2400 when testing is performed at a different location.