Flu Vaccine CPT Codes and Billing: 2026-2027 Season Guide

By Awais Afzal, Healthcare Operations & Data Analyst · Published February 23, 2026 · Updated October 14, 2026

Flu vaccine CPT codes for 2026-27 follow the product you give: 90656 covers Fluarix, FluLaval and Fluzone prefilled syringes, 90662 is high-dose and 90616 is the new mRNA vaccine. Medicare Part B reports the shot administration with G0008 and the diagnosis Z23. Always confirm the code against the product label.

Most flu claim errors start at the vaccine shelf, not at the billing desk: a product is stocked, a code is guessed and the claim carries a code that no longer matches. This guide is for practice owners and billing managers who give flu shots and want the 2026-27 codes in one place. It was checked in October 2026 against a New York City health department code letter dated September 1, 2026, CDC vaccine code set release notes, the AMA vaccine descriptor file and CMS transmittal 13859. Where a primary source could not be fetched, the post says so. For the other fall vaccines, see our guides to the CPT code for RSV vaccine and the shingles vaccine CPT codes.

Which flu vaccine CPT code do you bill? It depends on the product

Each flu vaccine product has its own CPT code, so the code on the claim must match the box that was opened. Table 1 lists the products on one health department’s 2026-27 code letter; the same letter tells providers to review their own vaccine records for miscoded and missing entries.

Source: New York City Department of Health, Update Your Flu Vaccine Codes 2026-2027 (September 1, 2026); CDC vaccine code sets release notes of August 20 and September 18, 2026 confirm 90616/CVX 338 and 90661/CVX 153.

Two points on the table. First, all of the products above are trivalent, which means a claim or an internal price list that still says quadrivalent is out of date. The CDC’s 2025-26 recommendations already described a trivalent-only market, and the 2026-27 product list above keeps that pattern. Second, the New York letter is a state and local source, not CDC itself. CDC’s own code-set pages were not reachable in this review, so confirm each row against the current CDC release notes and your CPT code set before loading it into your system.

The same letter says that brand names used for ordering (Fluarix, FluLaval and FluMist) are not the manufacturer to report; use the MVX code for the manufacturer listed on the FDA biologics license. It also asks providers to report the Sale NDC from the vaccine box, not the Use NDC, and to send the MVX, CVX and NDC together. That applies to the immunization record you send to the registry, but a mismatch between what is in the chart and what is on the claim is a common reason for rework. A short explainer on how HCPCS and CPT codes differ helps new staff see why Medicare uses G and Q codes alongside CPT.

What is new for 2026-27: an mRNA flu vaccine and code 90616

The one real coding change for this season is a new mRNA flu vaccine. mFLUSIVA from Moderna was approved by the FDA on August 5, 2026 for adults 50 and older, and CDC’s August 20 release notes list it with CVX 338 and MVX code MOD, as a 0.38 mL dose.

In the AMA’s vaccine descriptor file, CPT 90616 is the trivalent mRNA influenza vaccine at 37.5 mcg per 0.38 mL for intramuscular use. The file shows the code as new, with the FDA-pending symbol removed once approval came on August 5, and it says the code took effect July 1, 2026. The file also lists a second new mRNA influenza code, 90639, with a 50 mcg per 0.5 mL descriptor. We did not find a 2026-27 product mapped to 90639 in the CDC or health department lists, so do not use it until a product is mapped to it.

AAFP’s 2026-27 guidance, which cites CDC interim considerations dated September 1, 2026, lists mFLUSIVA among the options that adults 65 and older should preferentially receive when available, along with high-dose, adjuvanted and recombinant vaccines. For adults 50 to 64 it is age-appropriate with no preferential status. That matters for stocking and age edits, because a 90616 claim for a patient under 50 is outside the listed age range.

Source: AMA, CPT vaccine code descriptors (updated August 14, 2026); New York City Department of Health (September 1, 2026); CDC release notes (August 20, 2026).

Medicare Part B: how a flu shot claim is paid

Medicare Part B covers the seasonal flu shot, and the vaccine is paid at 95 percent of average wholesale price, with no deductible or coinsurance. The rules below come from CMS transmittal 13859, issued July 16, 2026, and the CMS flu shot provider page.

Source: CMS Transmittal 13859, Change Request 14542 (July 16, 2026); CMS, Flu shot provider page (last modified March 10, 2026); First Coast Service Options (MAC) page dated August 3, 2026.

Three details are easy to miss. The CMS transmittal tells contractors to reprocess claims paid at other allowances this season and to start a mass adjustment by November 1, 2026, so an early-season payment may change. It also names HCPCS code Q2039 as a code contractors must price this season, but it does not explain it, so check the CMS seasonal influenza pricing file for the product and payment amount before you use it. And the CMS provider page says home administration can carry an additional payment, starting January 1, 2024, under certain conditions.

We did not verify the dollar payment for G0008 or the price per product code, because the CMS pricing page was not reachable in this review. Pull both from the current CMS pricing files instead of copying a number from a blog. Our guide to how to verify Medicare coverage covers the eligibility step that comes before the claim.

Age rules and product choices that should drive your claim edits

Age limits on the product label are the easiest edits to automate, and they catch a large share of wrong-code claims. Table 1 already shows them: FluMist is for people 2 to 49, Flublok for 9 and older, and the high-dose and adjuvanted vaccines for 65 and older.

AAFP’s 2026-27 guidance, which says it is consistent with AAP and ACOG, adds context that affects who gets which product:

• Annual vaccination is recommended for everyone 6 months and older without a contraindication.
• Adults 65 and older should preferentially receive a high-dose, adjuvanted, recombinant or mRNA vaccine when available. If none is available, any age-appropriate vaccine is acceptable.
• FluMist is not for children under 2 or adults over 49. Adults 18 to 49 may self-administer it, and a caregiver 18 or older may give it to recipients 2 to 17.
• September and October are the best months for most people. July and August are generally discouraged for most adults, especially those 65 and older.
• Children 6 months to 8 years who need two doses should get them at least 4 weeks apart.
• Pregnant patients can receive an inactivated or recombinant vaccine in any trimester, and FluMist is not for use during pregnancy.

These are clinical recommendations, so they belong to your clinicians, not your billing team. The billing takeaway is narrower: a two-dose child series means two product codes and two administrations, an early July or August dose in an older adult may be questioned in an audit, and a 90616 or 90662 claim for the wrong age group will not hold up. Our guide to claim scrubbing explains how to turn rules like these into edits that run before submission.

Where flu claims break, and how to catch it before submission

Flu claims are high volume and low value per line, so one repeated error becomes a large write-off by the end of the season. The errors below follow directly from the rules in this guide.

• Wrong product code. The code on the claim does not match the vaccine drawn, often because an old price list was never updated.
• Age outside the label range. For example, 90662 or 90653 for a patient under 65, or 90616 for a patient under 50.
• Wrong Medicare setup. Medicare Part B claims need the vaccine code, G0008 and Z23, and the provider must accept assignment.
• Stale payment expectations. Medicare reprocessing for the 2026-27 allowances can change early-season payments.
• Use of codes that are not flu codes. Pulling 90624 or 90684 from an old list instead of a current flu product code.

If these errors repeat, the cause is usually in intake, charge entry or the vaccine price list, not in the billing office. Our medical billing and coding support is built around finding that upstream cause.

Our recommendations

1. Build a product-to-code list every August. Create one page that lists each flu product you stock, its CPT and CVX code and its age range. Have one named person review it against CDC release notes and the CPT code set each August and after each new release.
2. Match the code to the box, not the order form. Staff who record the dose should read the product name and code from the box actually used. Brand names used for ordering are not always the manufacturer to report.
3. Add age edits for the age-restricted products. Set edits for FluMist, Flublok, the high-dose and adjuvanted vaccines and mFLUSIVA so a wrong-age claim stops before submission.
4. Set a Medicare Part B template. For Medicare patients, build a charge template that carries the product code, G0008 and Z23, and confirm your practice accepts assignment for the vaccine.
5. Watch the early-season remits. Compare the first Medicare flu payments of the season against the CMS pricing file. CMS has told contractors to reprocess claims paid at other allowances, so adjustments are possible.
6. Retire every pre-2026 flu code list. Remove old spreadsheets, templates and quick-reference sheets that still show quadrivalent products or codes that do not belong to flu vaccines.

Bottom line

Flu vaccine billing is a product-to-code matching job, and 2026-27 adds one new code, 90616, to a trivalent-only list. Check the box, the age and the benefit before each claim goes out, and re-check the list when CDC and CMS update their files. If recurring denials point to a process gap, our denial management services team can trace them to the source, or you can contact us about a specific claim. You can also estimate what small leaks cost with the Revenue Calculator.

Frequently asked questions

What is the CPT code for a flu shot?

There is no single code. The CPT code follows the product: for example 90656 for Fluarix, FluLaval and Fluzone prefilled syringes, 90662 for Fluzone High-Dose and 90616 for the new mRNA vaccine mFLUSIVA. Read the code from the vaccine you actually gave, and confirm it against the current CPT code set.

What is new for flu vaccine billing in 2026-27?

The main change is CPT 90616 for mFLUSIVA, an mRNA flu vaccine the FDA approved on August 5, 2026 for adults 50 and older. CMS also issued new Medicare Part B payment allowances effective August 1, 2026. The sources reviewed show trivalent products only.

How does Medicare Part B pay for a flu shot?

Medicare Part B pays the vaccine at 95 percent of average wholesale price, with no deductible or coinsurance, and providers must accept assignment. Hospital outpatient departments, rural health clinics and FQHCs are paid reasonable cost. Administration is reported with G0008 and the diagnosis is Z23.

Are 90637, 90638, 90624 and 90684 flu vaccine codes?

Not as the old 2024-25 post described them. The AMA file shows 90624 as a meningococcal vaccine code, 90684 is not a flu code, and no fetched source supports 90637 and 90638 as quadrivalent mRNA flu codes. Use current product codes from CDC or the CPT code set.

Can Medicare cover two flu shots in one year?

Yes, in one situation. CMS says Medicare pays for two shots in a calendar year if they are given in two different flu seasons, such as one in January for the prior season and another in the fall. Additional shots are covered when medically necessary.

Where can we find the official flu vaccine code list?

Start with the CDC vaccine code sets page and its release notes, the AMA CPT vaccine code descriptors and the CMS seasonal influenza vaccine pricing page. Your Medicare Administrative Contractor and commercial payers may add their own policies, so check each one.

Sources

1. Update Your Flu Vaccine Codes 2026-2027 — New York City Department of Health (2026)
2. CDC vaccine code sets release notes, 8/20/2026 — CDC (2026)
3. CDC vaccine code sets release notes, 9/18/2026 — CDC (2026)
4. CPT vaccine medium descriptors (updated August 14, 2026) — American Medical Association (2026)
5. Transmittal 13859, Change Request 14542: Influenza vaccine payment allowances 2026-2027 — CMS (2026)
6. Flu shot (provider page) — CMS (2026)
7. 2026-2027 influenza, pneumococcal and hepatitis B vaccine reimbursement — First Coast Service Options (Medicare Administrative Contractor) (2026)
8. Prevention and control of seasonal influenza with vaccines: 2026-27 recommendations — American Academy of Family Physicians (2026)
9. Prevention and Control of Seasonal Influenza with Vaccines, 2025-26 (MMWR 74(32)) — CDC (2025)