Fecal Occult Blood Test — NCD 167 | CMS Coverage Update

CMS modified NCD 167 for fecal occult blood tests, effective March 7, 2026. Here's what billing teams need to know.

The Centers for Medicare & Medicaid Services updated NCD 167, the National Coverage Determination governing Medicare coverage of fecal occult blood testing (FOBT). This policy change clarifies medical necessity criteria, coding distinctions between diagnostic and screening indications, and frequency limitations that directly affect reimbursement. The policy does not list specific CPT or HCPCS codes in the available data, but the billing guidance below is derived entirely from the NCD 167 policy text.

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Quick-Reference Table

Field	Detail Copy
Payer	CMS (Centers for Medicare & Medicaid Services)
Policy	Fecal Occult Blood Test — NCD 167
Policy Code	NCD 167
Change Type	Modified
Effective Date	2026-03-07
Impact Level	Medium
Specialties Affected	Gastroenterology, primary care, internal medicine, clinical laboratory
Key Action	Verify that your team codes diagnostic FOBT separately from colorectal cancer screening FOBT — they use different HCPCS codes and frequency rules

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CMS Fecal Occult Blood Test Coverage Criteria and Medical Necessity Requirements 2026

The CMS fecal occult blood test coverage policy under NCD 167 covers FOBT under two distinct circumstances: diagnostic testing and colorectal cancer screening. These are not interchangeable. They report under different HCPCS codes, carry different frequency limits, and meet different medical necessity standards. Mixing them up is one of the fastest ways to generate a claim denial.

For diagnostic FOBT, medical necessity is established when one of four clinical conditions is present. Your documentation must support one of these:

These are the indications CMS accepts. If the chart doesn't document one of them, diagnostic coverage doesn't apply.

The range of conditions that can justify diagnostic testing is broad. It includes inflammatory causes like acid-peptic disease, Crohn's disease, ulcerative colitis, and NSAID use. Vascular causes include angiodysplasia, varices, and hemangiomas. Neoplastic causes include adenocarcinoma, lymphoma, and GI metastases. Extraintestinal causes — hemoptysis, epistaxis, hematuria, menstrual bleeding — can also trigger testing, though CMS notes these as "artifactual" sources of fecal blood. Document the specific clinical reason, not a generic "blood in stool."

The NSAID patient rule is specific. For patients on NSAIDs with a history of GI bleeding but no other current signs, symptoms, or complaints, diagnostic FOBT is covered no more than once every three months. This isn't a general guideline — it's a hard frequency limitation. Bill beyond that without supporting documentation and you're looking at a denial or a takebacks audit.

For colorectal cancer screening FOBT — where there are no signs, symptoms, or conditions associated with GI blood loss — a separate HCPCS code applies. The policy summary references this distinction explicitly: "When testing is done for the purpose of screening for colorectal cancer in the absence of signs, symptoms, conditions, or complaints associated with gastrointestinal blood loss, report the HCPCS code for colorectal cancer screening." The full HCPCS code text was truncated in the policy data, but this split between diagnostic and screening billing guidelines is the central point of the policy.

The real issue here is documentation. Medical necessity lives in the chart, not the claim. If your providers aren't documenting the specific indication — the symptom, the complaint, the underlying condition — your billing team is building claims on a foundation that won't hold up to a MAC audit.

Prior authorization is not referenced as a requirement under NCD 167. However, your Medicare Administrative Contractor may have a local coverage determination that adds documentation or coverage requirements on top of this NCD. Check your MAC's LCD for FOBT before assuming NCD 167 is the only rule in play.

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CMS Fecal Occult Blood Test Exclusions and Non-Covered Indications

NCD 167 doesn't carry a long exclusions list, but there are two limitations that function like coverage restrictions.

First, FOBT reports once for the testing of up to three separate specimens. Whether the lab runs one test or two tests per specimen, the billing is one unit. Billing multiple units for a single round of specimen testing is incorrect under this policy.

Second, the guaiac-based test — the most widely used of the three FOBT types — has a known limitation for screening use. CMS notes that guaiac-based testing should be deferred if other colon studies are performed before the test, because prior colon procedures affect reactivity. Similarly, recent meat ingestion can produce a false positive. These aren't billing exclusions, but they affect whether a test result is defensible under medical necessity review. A positive result triggered by a recent colonoscopy prep or a steak dinner is the kind of thing that surfaces in an audit.

The policy also notes that fecal hydration — adding water to the specimen — increases reactivity and false positivity rates. This is a clinical note, not a coverage rule, but it matters if a payer questions whether a positive result was clinically valid.

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Coverage Indications at a Glance

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CMS Fecal Occult Blood Test Billing Guidelines and Action Items 2026

The effective date of March 7, 2026 is already here. If your team hasn't reviewed FOBT workflows against the updated NCD 167, do it now.

Copy Action Items

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CPT, HCPCS, and ICD-10 Codes for Fecal Occult Blood Testing Under NCD 167

The available policy data for NCD 167 does not list specific CPT or HCPCS codes. This is a known limitation of the policy document as published.

What the Policy Text Tells Us

The policy explicitly distinguishes two coding paths:

• Diagnostic FOBT — used when one of the four covered indications is present (GI bleeding workup, unexplained anemia, abnormal symptoms, or stool color complaints). Your MAC's LCD or CMS claims processing instructions will define the applicable HCPCS code.
• Screening FOBT for colorectal cancer — used when there are no signs, symptoms, or conditions associated with GI blood loss. A separate HCPCS code applies. The policy text references this code but was truncated in the available data.

Where to Find the Codes

Check these sources for the definitive HCPCS codes under NCD 167:

Do not guess at codes based on prior years. HCPCS Level II codes for FOBT have changed before, and applying the wrong code — even with correct documentation — generates a denial that's avoidable.

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