UnitedHealthcare® Commercial Plan Registrations for Molecular Diagnostic Testing

Published 05/02/2023

UnitedHealthcare® commercial plans will begin to require providers to submit DEX Z-Codes™ for molecular diagnostic tests beginning on August 1, 2023, in accordance with a reimbursement policy update of the Molecular Pathology reimbursement Policy, Professional and Facility.

Other Commercial payers may similarly start utilizing and requiring the use of Z-Codes. If you have been notified by your Commercial Payer that this applies to your billed services, you are subject to this notice and are urged to comply with the instructions below.

Providing the Z-Code on a claim, with the appropriate CPT® code, will clearly identify the test being performed and eliminate some of the administrative burden you may encounter surrounding billing for these services. This requirement applies to both facility and professional claims.

Laboratories not currently registered with the DEX™ Diagnostic Exchange Registry that plan to submit molecular diagnostic claims are urged to sign up today by visiting www.dexzcodes.com. To allow sufficient processing time for both providers and DEX™ Registry processing, a limited number of CPT codes will be part of Wave I. After this wave, there will be several upcoming waves until the codes within scope are completed. If you bill with one of the CPT codes on the corresponding list, or perform services as described below, you will need to register in the DEX Registry for Z-Code assignment at this time.

View a list of CPT codes in Wave I (PDF)

The scope of services requiring Z-Codes includes:

  • All adult molecular diagnostic tests that are relevant to the Medicare age population (age 65+)
  • Prenatal cell-free DNA Screening (PCFS) (formerly Noninvasive Prenatal Screening (NIPS))
  • Prenatal Carrier Screening tests
  • Specific services billed under 81479*
    • Genetic disease carrier status for procreative management
    • Pharmacogenomics testing (PGx) including single gene and multi-gene panel


Why submit your test(s) before the deadiline:

Enforcement of Z-Codes will occur on August 1, 2023. Submitting your tests as soon as possible will:

  • Allow time to identify and fix possible errors or omissions with your test submission.


What to expect after you complete your registration:

  • The initial review for Z-Code assignment takes approximately 2 weeks from test submission.
  • The Z-Code can be submitted on claims once you have received email notification that the test has been assigned a recommended CPT® code and the assessment is complete. This typically occurs within 60 days from Z-Code assignment.
  • Additional documentation may be required dependent on test complexity. In which case you will be notified by email.
  • For further guidance on the timeline for the registration of your tests, refer to DEX Diagnostics Exchange Test Registration.


Have more questions?

  • If you have any questions or are not sure if your test requires submission now or in the future, please visit the DEX Website for more information or contact customer service at DEX.customer.service@palmettogba.com.
  • Upcoming communications will alert you to additional CPT code lists and timing.