Yes, Medicare covers Twinrix, the combination vaccine for hepatitis A and hepatitis B. Coverage runs through Medicare Part D rather than Part B, and for most beneficiaries the out-of-pocket cost is zero thanks to a rule that took effect January 1, 2023 eliminating cost-sharing for adult vaccines recommended by the CDC’s Advisory Committee on Immunization Practices.1CMS. Anniversary of the Inflation Reduction Act Update on CMS Implementation
Why Twinrix Is a Part D Vaccine
Medicare splits vaccine coverage. Part B pays for a short list: flu, pneumonia, COVID-19, and hepatitis B for people at medium or high risk. Everything else that is commercially available and medically reasonable for prevention falls to Part D, the prescription drug benefit.2CMS. Medicare Part D Vaccines
Twinrix contains a hepatitis B component, but Medicare treats it as a combination product rather than splitting it across the two benefits. Plan vaccine guides confirm the placement. A 2026 CDPHP Medicare Advantage vaccine guide lists Twinrix under Part D while placing stand-alone hepatitis B vaccines such as Engerix-B, Recombivax, and PreHevbrio under Part B for members at moderate to high risk.3CDPHP. Vaccine Coverage Guide Part B vs Part D An HMSA Medicare Advantage billing guide classifies CPT code 90636, the billing code for Twinrix, as not covered by Part B and covered under Part D.4HMSA. Immunizations Medicare Advantage Billing Guidelines
If you have Original Medicare without a Part D plan, Twinrix is not covered. Enrollment in Part D, either standalone or bundled into a Medicare Advantage plan, is what makes the vaccine payable.
What You’ll Pay
Nothing, in most cases. The Inflation Reduction Act requires Part D plans to waive all deductibles, copayments, and coinsurance for adult vaccines recommended by ACIP. The rule took effect January 1, 2023 and applies even when the vaccine is administered by an out-of-network provider.5ASPE. IRA Elimination of Vaccine Cost Sharing
Twinrix qualifies. The CDC’s 2025 adult immunization schedule lists Twinrix as an option for both the hepatitis A and hepatitis B series,6CDC. Recommended Adult Immunization Schedule, United States and that ACIP recommendation is what triggers the $0 cost-sharing rule.
For comparison, without insurance Twinrix runs roughly $140 to $195 per dose depending on the pharmacy, based on 2026 pricing.7GoodRx. Twinrix Price A full three-dose series could exceed $400 out of pocket without Part D coverage.
Where to Get the Shot and How Billing Works
The easiest place is an in-network pharmacy. The pharmacist bills your Part D plan directly for both the vaccine and the administration fee, and you pay nothing at the counter.2CMS. Medicare Part D Vaccines
A doctor’s office is more complicated. CMS defines Part D plan networks as pharmacy-only networks, so a physician’s office is technically out-of-network for Part D purposes.2CMS. Medicare Part D Vaccines You are still entitled to $0 cost-sharing, but the billing path is different. Some doctors can submit the claim directly to the Part D plan through an online portal or a claim form. Others will ask you to pay upfront and seek reimbursement from your plan.
If you are asked to pay at a doctor’s office, take these steps:
- Get an itemized receipt showing the provider’s name and address, the patient’s name, the date of service, the vaccine name and CPT code 90636, and a separate line for the administration fee.8GSK Pro. Twinrix Coding
- Contact your Part D plan and ask for a vaccine claim form or reimbursement instructions. Plans must supply a vaccine-specific notice with billing details.2CMS. Medicare Part D Vaccines
- Submit the form and receipt together. The plan should reimburse you, though the amount may be based on the plan’s allowed amount rather than what the provider charged.
Because of the billing friction, calling ahead to confirm how your doctor handles Part D vaccines can save a lot of paperwork. When in doubt, use a pharmacy.
Prior Authorization and Plan Rules
Part D plans are permitted to apply prior authorization, step therapy, and quantity limits to vaccines.9Maryland DHMH. Medicare Immunization Fact Sheet Some plans may require approval before administering Twinrix, or may prefer that you get separate hepatitis A and hepatitis B vaccines instead of the combination product.
Some Blue Cross Blue Shield plans flag Twinrix and other hepatitis B vaccines for prior authorization specifically to decide whether the shot should be billed to the medical benefit under Part B or the pharmacy benefit under Part D.10BCBSM. Vaccine Guide PPO Retirees That is an administrative step rather than a coverage denial, but it can slow things down if the provider and plan don’t coordinate ahead of time. Check your plan’s rules before scheduling.
Medicare Advantage and Dual-Eligible Beneficiaries
Medicare Advantage plans that include Part D drug coverage follow the same vaccine rules as standalone Part D plans. Twinrix is covered under the Part D component of a Medicare Advantage plan at $0 cost-sharing, just as it would be under Original Medicare paired with a standalone Part D plan.11AARP. What Vaccines Does Medicare Cover Billing logistics can vary, so ask your plan how it prefers vaccines administered in a doctor’s office to be handled.
For people enrolled in both Medicare and Medicaid, both programs cover ACIP-recommended vaccines at no cost. Medicaid independently covers all ACIP-recommended adult vaccines for most beneficiaries without copays or cost-sharing.12NCOA. Medicare and Medicaid Now Fully Cover Preventive Vaccines Part D is usually the primary payer for dual-eligible individuals with Part D enrollment, and either way you should owe nothing.
Twinrix or a Stand-Alone Hepatitis B Shot
If you only need hepatitis B protection, stand-alone vaccines such as Engerix-B, Recombivax, Heplisav-B, and PreHevbrio are available and covered. Part B pays for these at no cost for people Medicare considers at medium or high risk,13Medicare.gov. Hepatitis B Vaccines a group that includes people with end-stage renal disease, hemophilia, diabetes, or those living with a hepatitis B carrier.14Medicare Interactive. Hepatitis B Shots People at low risk get hepatitis B vaccines through Part D instead.15Noridian Medicare. Hepatitis B Virus Vaccine and Administration
Either way, cost-sharing is zero. The practical difference is billing. Part B claims run through the standard medical billing system, which makes doctor’s office administration straightforward. Part D claims run through the pharmacy benefit, which is why Twinrix at a doctor’s office can trigger the reimbursement dance described above.
Twinrix goes through Part D no matter your hepatitis B risk level, because Medicare classifies it as a combination product rather than a stand-alone hepatitis B vaccine.3CDPHP. Vaccine Coverage Guide Part B vs Part D If you’re at medium or high risk for hepatitis B and want the simplest billing experience at your doctor’s office, a stand-alone hepatitis B vaccine billed to Part B, plus a separate hepatitis A vaccine covered by Part D if you want that too, may be less trouble than Twinrix.