2025 Part D Late Enrollment Penalty Calculator

Avoiding the Medicare Part D Late Enrollment Penalty is possible if you act early. Learn how to avoid the Part D penalty at Medicare.gov, and use our calculator above to estimate what it could cost if you wait.

Part D Late Enrollment Penalty Overview

The Part D late enrollment penalty is a permanent addition to your Medicare drug coverage (Part D) premium if you experience a period of 63 or more consecutive days without Medicare drug coverage or other creditable prescription drug coverage after your Initial Enrollment Period. The penalty is calculated by multiplying 1% by the "national base beneficiary premium" and the number of full, uncovered months you were eligible for Medicare drug coverage but did not enroll.

Understanding Medicare Part D Late Enrollment Penalty Calculator.

• The Part D late enrollment penalty is a permanent addition to your Medicare drug coverage (Part D) premium if you experience a period of 63 or more consecutive days without Medicare drug coverage after your Initial Enrollment Period.
• The penalty is calculated as 1% of the "national base beneficiary premium" multiplied by the number of full, uncovered months you were eligible for Medicare drug coverage but did not enroll.
• In 2025, the penalty amounts to 1% of the "national base beneficiary premium" ($36.78), leading to a penalty of approximately $0.37 per uncovered month added to your monthly premium.

When is a Part D enrollment considered "late?"

Typically, enrollment is deemed late if you did not enroll within three months of initially receiving Original Medicare (Parts A and B).

Enrollment Exemptions

• You will be exempt from the Part D late enrollment penalty if you:
• Qualify for Extra Help, also referred to as the Part D Low-Income Subsidy (LIS)
  Have "creditable coverage" (coverage deemed comparable to Medicare drug coverage) from your or your spouse's employment, retiree benefits, or the Veterans Administration (VA)

Calculation of the Part D Late Enrollment Penalty

• The penalty calculation amount is rounded to the nearest $0.10 and is added to your monthly premium for your Medicare drug coverage.
• The penalty may increase annually due to the escalation in the "national base beneficiary premium."
• For example, delaying enrollment by 14 months may result in a 14% late enrollment penalty in addition to your monthly plan premium.

❗ Not sure how the penalty works? Jump to the calculator to get your estimate in seconds.

Avoid Part D Late Enrollment Penalty

• You may avoid paying a Part D penalty if:
  • You have creditable drug coverage (similar in value to Part D) or qualify for Extra Help.
• You may incur an extra 1% penalty for each month (12% annually) if you:
  • Don't join a Medicare drug plan when you first become eligible.
  • Go 63 days or more without creditable drug coverage.
• Your premium amount may also vary based on your income.

The best way to avoid the Part D penalty is to sign up for a Medicare Drug plan during your IEP.  For information about plans and signing up check out our online Medicare plan finder.

Penalty Duration and Exceptions

• The Part D late enrollment penalty remains in effect as long as you maintain Medicare drug coverage, regardless of switching plans.
• Individuals receiving Extra Help are exempt from paying the penalty.

Disputing the Part D Late Enrollment Penalty

• If you believe the penalty is inaccurate, you can request a reconsideration within 60 days of receiving the notice.
• Provide supporting evidence and submit the form to Medicare's contractor, who aims to make a decision within 90 days.
• Note that the penalty must be paid even if you disagree with it, with non-payment potentially resulting in disenrollment from your Medicare drug plan.

Outcome of the Reconsideration Decision

• If the contractor deems the penalty incorrect, adjustments will be made, and you may receive a refund.
• If the penalty is valid, you'll be required to pay as determined.

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