Medicare Coverage for Genetic Testing: LCD, NCD & MolDX (2026 Guide)

Short answer: Medicare covers genetic testing in two ways. A National Coverage Determination (NCD) sets a nationwide rule — most importantly NCD 90.2, which covers next-generation sequencing (NGS) for certain germline (inherited) and somatic (acquired) cancers. Everything the NCD doesn't address is decided locally by each Medicare Administrative Contractor (MAC) through a Local Coverage Determination (LCD). For most molecular tests, coverage runs through the MolDX program, which requires the specific test to carry a DEX Z-Code identifier and pass a technical assessment before it will be paid. A test is only reimbursed when it is (1) allowed under the relevant NCD or LCD, (2) medically necessary and supported by a documented, matching diagnosis code, and (3) ordered by a treating physician and run in a CLIA-certified lab.

This guide explains how those pieces fit together and how to check coverage for a specific test before you order it. It is educational — always confirm against the current CMS policy and the patient's MAC (see the disclaimer at the end).

NCD vs. LCD: national rule vs. local rule

For genetic testing, the practical result is: a small number of tests are governed by an NCD, and the large majority are governed by LCDs — which is why coverage for the same test can differ by the patient's geography and MAC.

NCD 90.2 — Next-Generation Sequencing (NGS)

NCD 90.2 is the national rule for NGS as a diagnostic laboratory test. Coverage requires the test to be performed in a CLIA-certified laboratory, ordered by the treating physician, and used to manage the patient. Within that, it splits into two paths:

Germline (inherited) cancer — covered nationally. Effective for dates of service on or after January 27, 2020, NGS is covered nationally for patients with germline breast or ovarian cancer who meet specific criteria — a clinical indication for hereditary breast/ovarian cancer, a risk factor for a germline mutation, and who have not been previously tested with the same germline NGS test for the same cancer. (MACs may extend coverage to other inherited cancers at their discretion.)

Somatic (acquired) cancer — MAC discretion for advanced disease. For patients with recurrent, relapsed, refractory, metastatic, or advanced (stage III or IV) cancer, MACs may cover NGS when it is used as a companion diagnostic (often FDA-approved or -cleared for that purpose), results are reported to the treating physician, and the patient has not already had the same NGS test for the same cancer.

The takeaway: NCD 90.2 is powerful but narrow — it is about NGS in a cancer context. Most other genetic tests fall to the LCD/MolDX process below.

The MolDX program, DEX Z-Codes, and the DEX registry

Most molecular diagnostic tests billed to Medicare are administered through MolDX, a program developed by Palmetto GBA (used by several MACs). MolDX exists to identify each molecular test, determine coverage, and set reimbursement. Two mechanics matter for anyone ordering or billing:

So in a MolDX region, coverage isn't just "does the LCD allow this indication?" — it's also "does this specific test have a Z-Code and a favorable coverage determination?"

Pharmacogenomic (PGx) testing coverage

Pharmacogenomic testing has its own coverage path. Medicare addresses PGx billing and coding in article A58801, and MolDX maintains PGx-specific policies. Coverage generally hinges on the patient being on, or a candidate for, a specific drug with an established gene–drug interaction (for example, a CPIC-guided pairing) — not on a standalone "genetic risk" rationale. Panel-based PGx and single-gene PGx are treated differently, and many payers restrict testing to genes with actionable, drug-specific evidence.

Medical necessity: coverage and coding have to agree

Even when a test is covered, the claim still fails if the diagnosis doesn't establish medical necessity. The ICD-10-CM code links the test to a documented reason the payer accepts; a vague code (like Z01.89) or a diagnosis that isn't on the LCD's covered list will be denied regardless of coverage policy. Getting this right is a two-sided check: the right coverage policy and the right supporting code, together. (See our companion guide, ICD-10 codes for genetic testing.)

How to check Medicare coverage for a specific genetic test

  1. Identify the patient's MAC (by the state where the service is furnished).
  2. Check for an NCD first (e.g., NCD 90.2 for NGS in cancer). If an NCD covers it, that rule governs nationwide.
  3. If no NCD applies, find the MAC's LCD and its Billing & Coding article in the CMS Medicare Coverage Database, and confirm the indication and the covered CPT/ICD-10 codes.
  4. In MolDX jurisdictions, confirm the test's DEX Z-Code and that MolDX has issued a favorable coverage determination for it.
  5. Document medical necessity in the chart and code it with a specific, matching ICD-10-CM code.

That reconciliation — right test, right indication, right coverage policy, right diagnosis code, correct Z-Code — is exactly what ScreenMyGene performs before an order goes out: it reads the chart, surfaces the panels the patient qualifies for, and anchors each to a supporting diagnosis code and coverage rule, so orders are defensible on the first submission. (See how it works.)

Frequently asked questions

Does Medicare cover genetic testing? Sometimes — it depends on the test and the indication. Some tests are covered nationally by an NCD (notably NGS for certain cancers under NCD 90.2); most others are covered locally by the patient's MAC through an LCD, and most molecular tests run through the MolDX program with a required DEX Z-Code.

What is NCD 90.2? The National Coverage Determination for next-generation sequencing. It covers NGS as a diagnostic lab test for certain germline (inherited) cancers nationally, and allows MAC-level coverage for somatic testing in advanced cancer, when performed in a CLIA-certified lab and ordered by the treating physician.

What is a MolDX Z-Code? A unique identifier (from the DEX registry) that specifies exactly which molecular test was performed. In MolDX regions, molecular test claims generally must carry the correct Z-Code to be adjudicated and paid.

Why is my genetic test not covered by Medicare? Common reasons: no NCD/LCD covers the indication for that patient's MAC; the specific test lacks a favorable MolDX determination or Z-Code; or the diagnosis code on the claim doesn't establish medical necessity for the test.

Does Medicare cover pharmacogenomic testing? Coverage is drug-specific and policy-dependent (see CMS article A58801 and MolDX PGx policies). It generally requires an established gene–drug interaction relevant to a medication the patient is taking or being considered for — not a general "risk" rationale.

Educational disclaimer: This article is for general informational purposes and summarizes Medicare coverage concepts as of 2026. Coverage policies (NCDs, LCDs, MolDX determinations, and PGx articles) change over time and vary by Medicare Administrative Contractor and patient circumstance. This is not coverage, billing, legal, or medical advice. Always verify against the current CMS Medicare Coverage Database and the applicable MAC/MolDX policy, and confirm with the ordering provider and a certified coder before submission. ScreenMyGene is clinical decision support and does not replace independent professional judgment.

Sources: CMS Medicare Coverage Database — NCD 90.2 (Next Generation Sequencing, NCDId 372) and CMS transmittal MM11837; Palmetto GBA MolDX program and DEX Diagnostics Exchange registry documentation; LCD L35025 (MolDX: Molecular Diagnostic Tests); CMS Billing and Coding: Pharmacogenomics Testing (A58801).