Distinct from the Part B late enrollment penalty on this site — Part D has its own penalty, based on a national base premium figure rather than your specific plan’s premium.
How it works
1% of the national base beneficiary premium, times the number of full uncovered months, rounded to the nearest $0.10, gives the monthly penalty — added to your plan’s premium for as long as you maintain Part D coverage.
What this does not include
This uses the 2026 national base beneficiary premium figure — that figure is recalculated annually, so the dollar penalty amount changes each year even though the percentage itself (based on uncovered months) stays fixed once determined.
How to use this calculator
- Enter the number of full months you went without Part D or other creditable prescription drug coverage.
Frequently asked questions
What counts as “creditable” drug coverage?
Coverage expected to pay, on average, at least as much as Medicare’s standard prescription drug coverage — such as coverage through a current employer or the VA — avoiding the penalty even without enrolling in Part D directly.
Is the penalty permanent?
Yes — once assessed, the penalty generally applies for as long as you have Medicare drug coverage, recalculated each year against that year’s new national base premium.
Is there a way to appeal the penalty?
Yes — a beneficiary who believes the penalty was calculated incorrectly, or who had creditable coverage during the gap, can request a formal reconsideration.
