Medicare Late Enrollment Penalties: How They Are Figured and How to Appeal

Here's the short answer. The Part B penalty is 10% of the standard Part B premium for each full 12 months you could have signed up but didn't. The Part D penalty is 1% of the national base beneficiary premium for each full month you went without drug coverage. Both are added to your monthly premium. Neither is a one-time fee. You can ask for a review of a Part D penalty. You have 60 days from the date on the letter.

The Part B late enrollment penalty

You pay an extra 10% for each year you could have signed up for Part B but didn't. Only full 12-month periods count. The penalty is added to your monthly Part B premium. You pay it each month for as long as you have Part B.

How to figure it. Count the full years you waited. Multiply by 10%. Then take that percent of the standard Part B premium.

Example for 2026 (Medicare.gov's own example). A person waited 2 full years (24 months) and did not qualify for a Special Enrollment Period. The penalty is 20%.

People with higher incomes may also pay an income-related surcharge on top. That is a separate charge. See how to ask for a lower IRMAA.

When you do not owe a Part B penalty

• You had similar coverage. Coverage from an employer can count, so you can wait to sign up. See Working Past 65.
• You qualify for a Special Enrollment Period.
• You join a Medicare Savings Program. See Medicare Savings Programs.

The Part D late enrollment penalty

You may owe this penalty if you go 63 days or more in a row without Medicare drug coverage or other creditable drug coverage. Creditable coverage is drug coverage that is about as good as Part D. It can come from an employer, a union, TRICARE, the VA, or Indian Health Service.

How to figure it. Take 1%. Multiply it by the national base beneficiary premium. Multiply that by the number of full months you went without coverage. Round to the nearest $0.10.

Example for 2026 (Medicare.gov's own example). A person waited 14 months and had no creditable coverage. The penalty is 14%. The national base beneficiary premium in 2026 is $38.99.

This is added to your plan's premium. It stays with you as long as you have Part D, even if you switch plans. The base premium can rise each year, so the penalty can rise too.

Extra Help removes it. You do not pay a Part D penalty while you get Extra Help. See Extra Help for Medicare drug costs.

Part B and Part D side by side

The Part A penalty is different. Most people get Part A with no premium and never see it. If you must buy Part A and wait, your premium may go up 10%. You pay it for twice the number of years you waited.

How to appeal a Part D penalty

You may ask for a "reconsideration." A Medicare contractor that is not connected to your drug plan does the review.

1. Read your plan's letter. It says you owe a penalty. Your plan will also send you information on how to ask for a review.
2. Count 60 days from the date on that letter. That is your deadline. If you send it late, you must explain why.
3. Fill out the form and send it back. Use the address or fax number on the form.
4. Include proof of creditable coverage. Examples are a copy of your prescription drug card or a notice of creditable coverage from an employer or union plan.
5. Wait for the decision. The contractor usually decides within 90 days. For good cause it may take 14 more days.

Keep paying while you wait. By law the penalty is part of your premium. You must pay it even if you ask for a review. A plan can disenroll members who do not pay premiums, including the penalty part.

If the contractor finds the penalty wrong, your plan removes or lowers it. The plan will send a letter that shows the right premium and says whether you get a refund. If the contractor finds it correct, you keep paying it. Sometimes the contractor will not review a request. For example, it may be late or incomplete. You generally do not get another chance to ask if you joined a different plan earlier and were already paying a penalty.

If you think your Part B penalty is wrong

The Medicare.gov pages we checked describe a formal review only for the Part D penalty. They do not lay out a separate Part B appeal process or deadline. Social Security handles Part B sign-up. If you had coverage that should have counted, or you think the number of years is wrong, start there. Call 1-800-772-1213 (TTY 1-800-325-0778). Have your dates of employer coverage ready. Your SHIP can help you for free. For the general appeal steps, see Appeals: Levels & Timelines.

Common questions

Related pages

• Enrollment & Deadlines
• Understanding Your Costs
• Medicare Part D
• Extra Help for Medicare Drug Costs
• Appealing IRMAA With Form SSA-44
• Glossary
• Medicare.gov: Avoid late enrollment penalties
• Medicare.gov: Part D costs