Information checked: 2026-09-10 · Maintenance label: Annual and policy variable
The Part D late enrollment penalty is not a one-time fee. It can follow the beneficiary for years and can change when the national base beneficiary premium changes.
The two facts to establish are the exact number of full uncovered months and whether other prescription coverage was creditable. Employer, union, VA, TRICARE, and other plans should provide creditable-coverage notices.
Key takeaway
A Part D penalty can apply after 63 or more consecutive days without Part D or other creditable drug coverage. It is generally 1% of the national base beneficiary premium for each full uncovered month, rounded to the nearest ten cents and added monthly for as long as Part D continues. If the coverage history is wrong, request reconsideration within the deadline in the letter, generally 60 days.
Table of contents
- When the penalty starts
- The calculation
- Check the coverage timeline
- How reconsideration works
- Prevent the next dispute
- Frequently asked questions
- Summary
Related guides
- Prescription Assistance Programs: How to Check Manufacturer and State Help
- Medicare Preventive Services 2027: What Part B Covers and When You May Still Pay
When the penalty starts
Medicare warns that going 63 days or more in a row after eligibility without Part D or other creditable prescription coverage may trigger the penalty. Discount cards, free clinics, samples, and cash-price programs are not insurance and do not count as creditable coverage.
Keep every annual creditable-coverage notice from an employer, union, or other plan. When a new Medicare plan asks about earlier coverage, return the form by its stated deadline.
The calculation
The monthly penalty is generally 1% of the national base beneficiary premium multiplied by the number of full uncovered months. The result is rounded to the nearest ten cents and added to the plan premium.
For 2026 Medicare lists a base beneficiary premium of $38.99. A 2027 penalty must use the 2027 base after CMS announces it; do not carry the 2026 number forward. Extra Help recipients do not pay the Part D late enrollment penalty while receiving Extra Help.
Check the coverage timeline
Mark the date Medicare eligibility began, every Part D enrollment, and each period of employer, union, VA, TRICARE, or other drug coverage. Identify gaps of 63 consecutive days or more and save termination and enrollment letters.
A plan's statement that coverage was creditable is stronger than a benefits summary that merely lists prescriptions. Ask the former plan for a replacement notice if needed.
How reconsideration works
If you disagree, the drug plan sends information and a reconsideration request. Medicare's current guide says to return it to the listed address or fax generally within 60 days of the penalty letter. Explain a late filing if the 60 days passed.
Attach proof such as creditable-coverage notices, plan cards, enrollment and termination letters, employer statements, or evidence that incorrect information caused the gap. Continue paying the billed premium while the review is pending unless the plan instructs otherwise.
Prevent the next dispute
Report coverage accurately when enrolling and respond to the plan's coverage questionnaire. Keep the submission confirmation. If you are approaching Medicare eligibility, ask the current plan in writing whether its prescription coverage is creditable.
Do not cancel employer or union coverage until the benefits administrator explains how Medicare enrollment affects the entire household's health coverage.
Frequently asked questions
What is the 63-day rule?
A penalty may apply after 63 or more consecutive days without Part D or other creditable drug coverage following eligibility.
Is the penalty permanent?
It is generally added for as long as you have Medicare drug coverage, although exceptions such as Extra Help can apply.
How long do I have to appeal?
The reconsideration form generally must be returned within 60 days of the date on the penalty letter.
Does a drug discount card count?
No. Medicare says discount cards and similar cash programs are not creditable prescription drug coverage.
Summary
A Part D penalty can apply after 63 or more consecutive days without Part D or other creditable drug coverage. It is generally 1% of the national base beneficiary premium for each full uncovered month, rounded to the nearest ten cents and added monthly for as long as Part D continues. If the coverage history is wrong, request reconsideration within the deadline in the letter, generally 60 days.