How is the Medicare Part D late enrollment penalty calculated?

Medicare multiplies 1% of the national base beneficiary premium ($34.70 in 2026) by the number of full uncovered months you went without Part D or other creditable prescription drug coverage after your Initial Enrollment Period, then rounds to the nearest $0.10 and adds it to your monthly Part D premium.

Does the Part D penalty go away eventually?

No. Like the Part B penalty, the Part D late enrollment penalty is generally permanent for as long as you have Medicare drug coverage, and it can increase each year because the national base beneficiary premium can change annually.

What counts as creditable prescription drug coverage?

Creditable coverage is drug coverage expected to pay, on average, at least as much as Medicare's standard Part D coverage — common examples include many employer or union plans, VA drug benefits, and TRICARE. Your plan administrator can confirm in writing whether your coverage was creditable.

Free Tool

Medicare Part D Late Enrollment Penalty Calculator

Estimate the monthly penalty added to your Part D premium if you went without creditable prescription drug coverage after becoming eligible.

When were you first eligible for Part D?

Did you have creditable drug coverage?

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When did that coverage end?

When are you enrolling in Part D?

Uncovered months0

Monthly penalty$0.00

This penalty is permanent.

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Informational purposes only. This is an educational estimate, not a determination of your actual penalty. Only your Part D plan and CMS can confirm your exact enrollment status and penalty. Price Services Group is an independent agency not connected with or endorsed by the U.S. government or the federal Medicare program.