Hepatitis Panel/Acute Hepatitis Panel — NCD 166 | CMS Coverage Update

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 166, the National Coverage Determination governing the Hepatitis Panel (Acute Hepatitis Panel), with an effective date of March 7, 2026. Here's what changes for billing teams.

CMS hepatitis panel coverage policy under NCD 166 covers four specific tests: Hepatitis A antibody IgM (HAAb-IgM), Hepatitis B core antibody IgM (HBcAb-IgM), Hepatitis B surface antigen (HBsAg), and Hepatitis C antibody. This policy applies to Medicare billing for acute hepatitis workups and governs when CMS will reimburse for this panel versus individual components. The policy does not list specific CPT or HCPCS codes in this version — more on that below.

Quick-Reference Table

CMS Hepatitis Panel Coverage Criteria and Medical Necessity Requirements 2026

NCD 166 in the Medicare system covers the Acute Hepatitis Panel when medical necessity for acute hepatitis workup is established. That means your documentation needs to show a clinical reason to test for active infection — not just screening or prior immunity confirmation.

The panel bundles four tests: HAAb-IgM, HBcAb-IgM, HBsAg, and Hepatitis C antibody. CMS will reimburse all four when ordered together as part of an acute hepatitis workup. Order individual components outside the panel context and your medical necessity documentation needs to justify each one separately.

The clinical logic matters here because the timing of these markers is baked into the coverage policy. HAAb-IgM appears within four weeks of exposure and disappears within three months — so ordering it outside that window raises a medical necessity red flag. HBsAg appears four to eight weeks post-exposure. HBcAb-IgM becomes detectable two to three months after exposure. If your clinician is ordering this panel months after a known exposure with no acute symptoms, expect scrutiny.

For HBV specifically, CMS distinguishes between acute and chronic infection. Acute HBV diagnosis requires a positive HBcAb-IgM and a positive HBsAg together. Chronic HBV diagnosis relies on HBsAg persistence beyond six months combined with positive HBcAb-IgG. The panel only covers the acute picture. If your clinical team is documenting chronic HBV, the full acute panel may not be appropriate — and billing it as such is a claim denial risk.

One situation CMS calls out explicitly: after a completed HBV vaccination series, HBsAb alone can be ordered monthly for up to six months, or until a positive result confirms adequate antibody response. That's a standalone order, not the full panel, and your documentation should reflect vaccination completion as the clinical context.

Prior authorization is not specifically required under NCD 166 for the hepatitis panel as a blanket rule. However, your Medicare Administrative Contractor (MAC) may have a local coverage determination (LCD) that adds prior auth or documentation requirements on top of NCD 166. Check your MAC's LCD before assuming NCD 166 alone governs your region.

CMS Hepatitis Panel Exclusions and Non-Covered Indications

NCD 166 does not cover every hepatitis-related test under the same umbrella. The panel is defined as four specific components. Tests outside those four — Hepatitis B e antigen (HBeAg), Hepatitis B e antibody (HBeAb), IgG anti-HAV — are not part of this panel and are not covered under NCD 166.

CMS specifically notes that HBeAg and HBeAb "may be of importance in assessing the infectivity of patients with HBV" but excludes them from the panel. If your clinicians need these for infectivity assessment, bill them separately with their own medical necessity documentation.

IgG anti-HAV indicates prior effective immunization or recovery from past infection. CMS does not cover this as part of the acute panel because it does not diagnose acute disease. Ordering IgG anti-HAV as part of an acute workup and billing it under the panel logic is a documentation mismatch — and that's how claim denials happen.

Hepatitis D and Hepatitis E are not addressed by NCD 166 at all. Coverage for those would fall under separate determinations or MAC-level policy.

Coverage Indications at a Glance

CMS Hepatitis Panel Billing Guidelines and Action Items 2026

The real issue with NCD 166 is documentation timing. The markers in this panel are time-sensitive. Your clinical documentation needs to reflect where the patient is in the exposure timeline — not just "rule out hepatitis." Here's what your billing team should do before March 7, 2026.

If you're unsure how NCD 166 interacts with your MAC's LCD or how your current documentation holds up against these criteria, talk to your compliance officer before the March 7, 2026 effective date.

CPT, HCPCS, and ICD-10 Codes for Hepatitis Panel Under NCD 166

A Note on Codes for This Policy

NCD 166 in this version does not list specific CPT, HCPCS, or ICD-10 codes. This is not unusual for older NCDs that predate the current coding structure — but it creates a real problem for hepatitis panel billing teams.

You need to confirm the applicable codes directly with your MAC or through your clinical laboratory's billing guidelines. The four panel components that CMS covers under this policy are:

• Hepatitis A antibody (HAAb), IgM antibody
• Hepatitis B core antibody (HBcAb), IgM antibody
• Hepatitis B surface antigen (HBsAg)
• Hepatitis C antibody

Each of these maps to a specific CPT code in your charge description master. Do not assume the panel bundles under a single code without verifying with your MAC — some contractors require individual component codes, and some accept a panel code. Getting this wrong is a reimbursement problem that compounds across high-volume lab billing.

Do not use codes that aren't confirmed against the actual NCD 166 policy data and your MAC's guidance. Fabricated or assumed codes create audit exposure.