CMS Modified NCD 204 for Obsolete Diagnostic Tests, Effective March 7, 2026 — What Billing Teams Need to Know

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 204, its coverage policy governing obsolete and unreliable diagnostic tests, effective March 7, 2026. These tests don't get routine payment — but a documented medical necessity exception still exists, and your billing team needs to know exactly how to use it.

NCD 204 in the Medicare system covers two categories of non-payable tests: general diagnostic tests deemed obsolete, and cardiovascular phonocardiography and vectorcardiography tests deemed outmoded. This policy does not list specific CPT or HCPCS codes — it describes tests by name, which creates real documentation and charge capture challenges for billing teams who need to map these to the codes in their system.

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Quick-Reference Table

Field	Detail Copy
Payer	CMS / Medicare
Policy	Obsolete or Unreliable Diagnostic Tests
Policy Code	NCD 204
Change Type	Modified
Effective Date	2026-03-07
Impact Level	Medium
Specialties Affected	Clinical laboratory, cardiology, gastroenterology, endocrinology, allergy/immunology, internal medicine
Key Action	Audit your charge master for any tests listed under NCD 204 and confirm your documentation process for physician-justified medical necessity exceptions before March 7, 2026

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CMS Obsolete Diagnostic Test Coverage Criteria and Medical Necessity Requirements 2026

NCD 204 is the National Coverage Determination governing Medicare coverage — or more accurately, Medicare non-coverage — of a defined list of obsolete and outmoded diagnostic tests. The Centers for Medicare & Medicaid Services does not routinely pay for these tests. That's the baseline.

The exception matters. CMS will pay for these tests if the ordering physician provides satisfactory medical justification. This isn't a blanket prior authorization requirement — it's a documentation standard. The physician who performs the test must justify the medical need.

Who reviews that justification depends on the claim. If the service is subject to Quality Improvement Organization (QIO) review, the QIO makes the call. If it's not subject to QIO review, the A/B Medicare Administrative Contractor (MAC) responsible for that jurisdiction reviews and decides. Your billing team should know which MAC handles your claims, because that determines where a disputed claim lands.

This structure creates a coverage policy with a narrow exception — not a hard exclusion and not a routine benefit. That middle ground is exactly where claim denial risk lives. A claim submitted without adequate physician justification documentation will not survive MAC or QIO review.

Category A: General Diagnostic Tests

CMS considers the following tests obsolete. They have been replaced by more advanced procedures and don't get routine reimbursement under Medicare:

These span laboratory chemistry, skin testing, gastric analysis, and cancer screening. If any of these appear in your charge master or test menu, the default answer from Medicare is no payment — unless documented justification exists.

Category B: Cardiovascular Tests

CMS separately excludes phonocardiography and vectorcardiography tests. These are not just obsolete — CMS has determined they are outmoded and of little clinical value. That's a stronger characterization than Category A, and it matters in appeals. The cardiovascular tests covered under this exclusion include:

The medical necessity exception in Category A does not clearly extend to Category B under the same terms. CMS uses the phrase "do not pay" without the qualifying exception language it uses for Category A. If your cardiology team is still running vectorcardiography or phonocardiography and billing Medicare, talk to your compliance officer before March 7, 2026.

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CMS Obsolete Diagnostic Test Exclusions and Non-Covered Indications

The real issue here is that NCD 204 is structured as a presumptive denial list with a safety valve. Category A tests are non-covered by default but payable with documented justification. Category B cardiovascular tests appear to have no safety valve — the policy language states "do not pay" without any exception pathway.

That distinction could cost you. If a physician orders a vectorcardiogram and believes they can justify it with medical necessity documentation, the billing guidelines under NCD 204 may not support that claim the way they would for a Category A test. Your MAC won't apply the Category A exception logic to Category B tests without explicit policy support, and this policy doesn't provide it.

Don't submit phonocardiography or vectorcardiography claims hoping the medical necessity argument holds. It won't. These tests should be removed from your charge capture for Medicare patients, full stop.

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Coverage Indications at a Glance

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CMS Obsolete Diagnostic Test Billing Guidelines and Action Items 2026

Here's what to do before the March 7, 2026 effective date — and after.

Copy Action Items

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CPT, HCPCS, and ICD-10 Codes for Obsolete Diagnostic Tests Under NCD 204

Policy Note on Codes

NCD 204 does not list specific CPT or HCPCS codes. CMS identifies these tests by descriptive name only. This is a meaningful gap for billing teams.

Your charge master likely maps these test descriptions to legacy CPT codes — many from the CPT code set's earlier editions. Some of these codes may have been deleted from the current CPT code set entirely. Others may have been renumbered or consolidated.

Because this policy does not list specific codes, do not rely on a code-matching approach alone. Use the test descriptions in the policy as your reference and map them against your current charge master manually. If you're not sure which codes in your system correspond to these descriptions, work with your coding team or billing consultant before March 7, 2026.

No Covered Codes Under NCD 204

There are no covered codes under this policy. NCD 204 establishes a non-coverage baseline for all listed tests. Payment is only possible via documented exception — not as a covered benefit.

Tests With No CPT Code Mapping Provided

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