Washington University Pathology Services
P.O. Box 60352
Campus Box 8118
St. Louis, MO 63160

Billing Office Phone: 314-747-1100

Office Hours: 8 a.m. – 5 p.m. (CST) | Monday – Friday (excluding holidays)

Washington University Pathology Services bills patients for deductible and co-insurance amounts, out-of-network penalties, and non-covered services. It is the patient/provider’s responsibility to obtain a referral for work sent to Washington University Pathology Services in the event the patient’s insurance carrier considers Washington University Pathology Services to be an out-of-network provider.

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WU-Pathology Services CLIA# NPI#
WU-AMP Core Lab26D20132031174880629
WU-Cytogenetics, FFPE FISH & GPS26D06982851043414113
WU-Dermatopathology Lab26D20571621487099768

Federal tax identification number


Washington University Pathology Services offers both direct patient/3rd party insurance and client billing as payment options.

Direct patient/third party billing

Washington University Pathology Services participates with the following major payers:

  • Aetna
  • Anthem
  • Cigna
  • Coventry
  • Missouri Medicaid
  • Missouri Medicare*
  • United Healthcare

WU-Pathology Services contracts with the above-listed plans are primarily within the St. Louis metro network. 

See full list of contracted plans »

Please Note: WU-Pathology Services does not enroll providers with Out of State Medicaid nor Out of State Medicaid MC+ plans. Cases received for patients covered under these programs, as well as non-contracted plans, will be returned to the client or billed to the client (if client opts to have the test performed regardless of the coverage limitation). Clients should contact the billing office to discuss billing & payment arrangements.

*Washington University Pathology Services will bill Medicare for all physician services as well as laboratory (technical) charges associated with office visits. However, laboratory (technical) charges associated with Medicare hospital outpatient or inpatient visits must be submitted to the client in accordance with the Benefits Improvement and Protection Act of 2000 (BIPA).

Client billing

Washington University Pathology Services produces client invoices on a monthly basis. The invoices itemize the date of service (collection date), patient name and date of birth, charge description, price and CPT code of each test performed. Payment of the invoice is due within 30 days of receipt. The client is responsible for applicable insurance and patient billing.

Current Procedural Terminology Coding (CPT)

CPT Codes are provided in the Washington University Pathology Services online test menu. Clients are encouraged to consult the CPT Coding Manual published by the American Medical Association and to address questions regarding the use of any particular code to their local Medicare carrier. CPT codes are subject to change at any time; therefore, it is the client’s responsibility to contact our billing department to discuss correct coding.

Advance Beneficiary Notification (ABN)

In the event a health care practitioner order tests that Medicare deems medically unnecessary, a properly executed Advance Beneficiary Notification (ABN) must be secured by the client prior to collection of the specimen. The ABN form must accompany the specimen to our laboratory. The ABN enables Washington University Pathology Services to bill the patient if Medicare denies our claim for medical necessity or frequency limitations. It is the client’s responsibility to ascertain the need for the ABN. In the absence of a properly executed ABN, Washington University Pathology Services will bill denied charges back to the client.

General requirements for direct patient/third party billing

A completed Washington University Pathology Services Test Requisition form must accompany the specimen and must contain the following information:

  • Referring physician’s complete first and last name (no initials)
  • Referring physician’s NPI number
  • ICD-10 diagnosis code (supporting medical necessity) for clinical lab testing
  • Patient name, address, DOB & gender
  • Primary insurance name and mailing address
  • Primary insurance policy number
  • Policyholder’s name & relationship to patient
  • Supplementary/secondary insurance name and mailing address (if applicable)
  • Supplementary/secondary subscriber name & insurance policy number
  • A copy of the patient’s insurance card (front & back) is desired
  • The correct birthdate of all pertinent insurance policyholders