Flu season arrives every year, but the billing details do not always stay the same. New products enter the market, NDCs change, payment allowances are updated, and administration requirements can vary by payer.

Before flu-vaccine volume increases, practices should review their EHR favorites, charge masters, vaccine inventory records and claim-scrubbing rules. A few minutes of preparation now can prevent weeks of denials, corrected claims and unnecessary accounts-receivable follow-up later.

The Three Components of a Flu-Vaccine Claim

A clean influenza-vaccine claim generally requires:

1. The CPT or HCPCS code for the specific vaccine administered
2. The appropriate vaccine-administration code
3. Diagnosis code Z23, Encounter for immunization

The product code must match the vaccine, dosage and formulation documented in the medical record. Billing a familiar flu-vaccine code without confirming the actual product is one of the easiest ways to create an avoidable denial.

2026–2027 Flu Vaccine Product Codes

The following products appear in the CMS 2026–2027 seasonal vaccine pricing file and NDC/HCPCS crosswalk issued August 27, 2026:

• 90616 mFLUSIVA Trivalent
• 90653 Fluad Trivalen
• 90656 Fluarix Trivalent
• 90656 FluLaval Trivalent
• 90656 Fluzone Trivalent, preservative-free
• 90657 Fluzone Trivalent, multidose vial
• 90658 Fluzone Trivalent, multidose vial
• 90660 FluMist Trivalent
• 90661 Flucelvax Trivalent
• 90662 Fluzone High-Dose Trivalent
• 90673 Flublok Trivalent

Most of these allowances are effective from August 1, 2026 through July 31, 2027. The exceptions are:

• 90616: Effective August 5, 2026
• 90660: Effective August 24, 2026

These amounts are CMS national product payment allowances based on 95% of Average Wholesale Price. They are not local administration rates, recommended charges or guarantees of payment. Payment methodology may also differ for hospital outpatient departments, Rural Health Clinics and Federally Qualified Health Centers.

Medicare Administration Coding

For Medicare Part B, report:

• G0008 – Administration of influenza virus vaccine
• Z23 – Encounter for immunization

The payment for G0008 is geographically adjusted and is separate from the vaccine-product allowance.

When the vaccine is administered in a qualifying patient’s home, M0201 may provide an additional payment. This code has specific Medicare eligibility, setting and frequency requirements. It should not be added automatically simply because a vaccine was administered outside the office.



For covered Medicare influenza vaccines and their administration, the Part B deductible and coinsurance do not apply. Providers and suppliers must accept assignment for the vaccine product.

Administration Codes for Other Payers

Commercial insurance, Medicaid and Medicare Advantage plans may follow different billing requirements. Depending on the payer and circumstances, administration coding may include:

• 90471 – First vaccine administered by injection
• 90472 – Each additional injected vaccine
• 90473 – First vaccine administered orally or intranasally
• 90474 – Each additional oral or intranasal vaccine
• 90460 – May apply when a qualified healthcare professional provides face-to-face counseling to a patient through age 18

Do not assume a Medicare administration code should be used for every payer. Likewise, do not assume every commercial plan follows the same age, counseling or administration requirements. Verification should be part of the practice’s preseason workflow.

Watch the Dose on Multidose Fluzone

Codes 90657 and 90658 share the same CMS-listed NDC because both refer to Fluzone Trivalent supplied in a multidose vial. The correct product code depends on the dose administered:

• Report 90657 for the 0.25 mL dose.
• Report 90658 for the 0.5 mL dose.

The dose documented in the medical record must support the code submitted on the claim.

NDC Reporting Still Matters

The NDC should match the exact product and package maintained in the practice’s inventory. Depending on the payer and electronic-claim format, the claim may also require:

• The 11-digit NDC format
• An NDC unit-of-measure qualifier
• The quantity administered
• Specific placement in the shaded area of the CMS-1500 claim or the corresponding electronic claim segment

Never select an NDC based only on the vaccine’s brand name. Confirm it against the vial, syringe, carton or inventory record used for that patient.

Documentation Checklist

The vaccine-administration record should include:

• Vaccine name and manufacturer
• CPT or HCPCS product code
• NDC
• Dose administered
• Route and administration site
• Lot number
• Expiration date
• Date of administration
• Name and credentials of the person administering the vaccine
• Vaccine Information Statement date and delivery information, when required
• Counseling documentation when reporting an administration code that depends on counseling

If a separately identifiable E/M service is provided on the same date, modifier 25 should only be appended when the documentation supports a significant service beyond the routine work associated with administering the vaccine.

Complete a Preseason Billing Review

Before submitting the first flu-vaccine claim of the season, practices should confirm that:

• Product codes match the vaccines currently in inventory.
• NDCs are loaded correctly.
• Dose-specific options are available to clinical and billing staff.
• Medicare and commercial administration codes are mapped correctly.
• Z23 is linked to the vaccine and administration services.
• Fee schedules are updated without treating the CMS allowance as a recommended charge.
• Staff understand when payer verification is necessary.
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CMS has indicated that the 2026–2027 file may be updated as additional products and pricing information become available. Practices should monitor the CMS Vaccine Pricing page throughout the season rather than relying solely on a preseason setup.

Accurate vaccine billing is not complicated when the workflow is built correctly. The key is making sure the product, dose, NDC, administration code and diagnosis all tell the same story before the claim leaves the practice.

This article is intended for general billing and coding education. Coverage, coding and payment policies vary by payer, provider type and service setting. Always verify current payer requirements before submitting claims.