The Medicare 14-Day Rule: How Lab Date of Service Works for Stored Specimens
Short answer: The Medicare 14-day rule sets the date of service for tests on a hospital patient's stored specimen. If a physician orders the test at least 14 days after discharge, the date of service is the test date, so the lab can bill Medicare. Sooner, the collection date applies, usually putting payment with the hospital.
What is the Medicare 14-day rule?
The 14-day rule is the common name for the laboratory date of service policy in 42 CFR 414.510. By default, the date of service for a clinical lab test is the date the specimen was collected. Date of service matters because it decides who bills. If the date falls inside a hospital stay or an outpatient encounter, payment for the test can be packaged into the hospital's payment, and the lab must look to the hospital rather than Medicare.
The rule creates a controlled exception for specimens that were collected during a hospital procedure and stored. Under 42 CFR 414.510(b)(2)(i)(A), one of the conditions is that the test be ordered at least 14 days following the date of the patient's discharge from the hospital. Noridian, the Medicare Administrative Contractor for the JF jurisdiction, explains the outcome in plain terms: when the test is ordered at least 14 days after discharge, the date of service is the date the test was performed instead of the date of specimen collection. If specimen collection spans two calendar days, the date of service is the date collection ended.
What conditions must be met for a stored specimen?
The 14-day timing is only one of several requirements. For specimens stored 30 calendar days or less, Noridian lists the full set: the test is ordered at least 14 days after discharge, the specimen was collected during a hospital surgical procedure, collecting it outside that procedure would have been medically inappropriate, the results did not guide treatment during the hospital stay, and the test was reasonable and medically necessary. If any one condition fails, the collection date stays the date of service.
Storage time changes the answer. For specimens stored more than 30 days, which Noridian calls archived, the date of service is the date the specimen was removed from storage. Chemotherapy sensitivity tests on live tissue carry a parallel condition: under 42 CFR 414.510(b)(3)(i), the decision about which chemotherapeutic agents to test must be made at least 14 days after discharge.
Is there an exception for molecular and ADLT testing?
Yes, but only for hospital outpatients. Under 42 CFR 414.510(b)(5), molecular pathology tests, advanced diagnostic laboratory tests (ADLTs), cancer-related protein-based multianalyte assays with algorithmic analyses, and the test described by CPT code 81490 can use the test date as the date of service when five conditions are met. The test was performed following the patient's discharge from the hospital outpatient department. The specimen was collected from the hospital outpatient during an encounter. It was medically appropriate to collect the sample then. The results do not guide treatment provided during that outpatient encounter. And the test was reasonable and medically necessary.
Noridian states the limit directly: for inpatient and non-patient encounters, this exception does not apply, and the collection date remains the date of service. That is the heart of the current debate. A lab can often bill separately for an outpatient biopsy sent for molecular profiling, but the same assay on an inpatient surgical specimen is subject to the 14-day timing.
What has CMS considered, and what is the current debate?
The outpatient exception grew out of rulemaking. In the CY 2018 Hospital Outpatient Prospective Payment System proposed rule, CMS said it was considering changes to the date of service regulation, and floated approaches that would let labs bill separately for molecular pathology tests and ADLTs ordered within 14 days of discharge. Comments were due September 11, 2017, according to a Mintz analysis published August 10, 2017. The result for outpatients is the exception now in the regulation.
The inpatient side is the open issue. A review of public discussion published October 2, 2026 on the Discoveries in Health Policy blog found no current CMS proposal to change the inpatient rule. It cites advocacy: a November 14, 2024 College of American Pathologists update describes support for a resolution urging that complex testing on inpatient specimens be payable separately, consistent with outpatient rules. That is an advocacy position, not a CMS action. The same review stresses that the rule is a payment and billing barrier and does not prohibit clinically indicated testing during the window, so statements that Medicare forbids early testing are inaccurate.
Why is the rule an enforcement risk for labs?
Because date of service decides who gets paid, it has attracted False Claims Act scrutiny. On October 2, 2023, the Department of Justice announced that Genomic Health, a wholly owned subsidiary of Exact Sciences, agreed to pay $32.5 million to resolve allegations that it improperly billed Medicare for tests used to diagnose and treat cancer. DOJ alleged the company sought to evade the 14-day rule for Oncotype DX. The government described four methods: billing Medicare directly for tests ordered within 14 days after an inpatient discharge, billing Medicare directly for tests ordered within 14 days of an outpatient procedure, encouraging hospitals and physicians to cancel and reorder tests, and failing to send timely invoices to hospitals while writing off the unpaid fees, which DOJ said violated the Anti-Kickback Statute. The whistleblowers received $5,687,500. The release states the claims are allegations only, with no determination of liability.
What should labs and revenue cycle teams do?
Build the date logic into order intake rather than relying on billers to catch it later. Record the discharge date, the specimen collection date, the order date, and the test performed date for every hospital-linked specimen. Noridian specifically advises documenting both the collection date and the test performed date. Then route each case by setting: inpatient, hospital outpatient, or non-patient. Only the outpatient molecular and ADLT exception allows a separate-billing path within the 14-day window.
Treat cancel-and-reorder patterns as a compliance flag, not a workaround. If an order is cancelled and placed again solely to land outside the window, the pattern resembles what DOJ described. Also confirm contract terms: when a hospital obtains outpatient lab services under arrangements, Noridian notes that only the hospital can bill for the arranged services. Finally, note that Noridian's own page says the term "date test performed" is not defined and words the day-14 boundary inconsistently, with "at least 14 days" in the text and "within 14 days" in the decision tree. Get written guidance from your Medicare contractor on edge cases, and keep results under review as part of your wider genetic testing denials prevention work.
For related reading, see our overview of Medicare coverage for genetic testing and the October 2026 lab NCD edit update. To check coverage criteria before an order is finalized, explore the ScreenMyGene platform.
Frequently asked questions
What is the Medicare 14-day rule for labs?
It is the date of service policy at 42 CFR 414.510. For a stored hospital specimen, if the test is ordered at least 14 days after discharge and other conditions are met, the date of service is the test performed date, letting the lab bill Medicare. Otherwise the collection date applies.
Does the 14-day rule stop doctors from ordering tests early?
No. A recent policy review notes the rule does not prohibit clinically indicated testing during the window. It is a payment and billing rule that affects who bills, which is why it can still influence ordering timing, hospital workflows, and how quickly molecular results reach the treating team.
Does the molecular test exception apply to inpatients?
No. Noridian states the molecular pathology and ADLT exception applies only to hospital outpatient encounters. For inpatient and non-patient encounters, the specimen collection date remains the date of service, so the standard 14-day timing governs the billing. Labs should confirm the care setting for every hospital-linked specimen before choosing a billing path.
How do stored specimens change the date of service?
For specimens stored 30 calendar days or less, the five stored-specimen conditions apply. For specimens stored more than 30 days, called archived, the date of service is the date the specimen was removed from storage, per Noridian guidance. Both dates, collection and test performed, should be documented in the record for every case.
Why did DOJ pursue a lab over the 14-day rule?
In October 2023, DOJ announced a $32.5 million settlement with Genomic Health over allegations of evading the rule through direct billing, cancel-and-reorder practices, and uncollected hospital invoices. The claims were allegations only, with no determination of liability, but the case shows date-of-service handling draws False Claims Act attention.
This article is educational and intended for laboratory, medical director, and revenue cycle professionals. It is not legal, coding, or reimbursement advice and does not replace CMS or Medicare contractor documents. Verify all policies against current regulations and contractor guidance before billing.
Sources: 42 CFR 414.510 (eCFR); Noridian Healthcare Solutions, Date of Service (DOS) Policy, JF Part B, updated June 30, 2026; U.S. Department of Justice, "Genomic Health Inc. Agrees to Pay $32.5 Million to Resolve Allegations Relating to Submission of False Claims," October 2, 2023; Mintz (K. Lovitch), "CMS May Decide to Permit Labs to Bill for Certain Tests Provided to Outpatients," August 10, 2017; Discoveries in Health Policy, October 2, 2026.