Part D Late-Enrollment Penalty
Understand creditable drug coverage, uncovered months, and long-term penalty exposure.
The uncovered-days trigger
You may owe a Part D penalty if, after you are first eligible for Medicare drug coverage, you go 63 continuous days or more without Part D or other creditable prescription coverage. An employer or other plan should tell you in writing whether its coverage is creditable.
Official source: Medicare: Avoid penalties ↗ · Medicare: Creditable drug coverage ↗
2026 calculation
The monthly Part D penalty uses 1% of the national base beneficiary premium, $38.99 for 2026, multiplied by the number of full uncovered eligible months; Medicare rounds the result to the nearest ten cents. The rate changes by year and is generally added to the monthly premium for as long as you have Medicare drug coverage.
Official source: Medicare: Part D costs ↗
Keep the creditable-coverage notice
Save the annual notice and exact dates your former drug coverage started and ended. You may be asked to attest to prior coverage. A low-drug-use year does not itself exempt a person from the late-enrollment rules.
Official source: Medicare: Creditable drug coverage ↗ · Medicare: Part D costs ↗
Check help and next steps
People who qualify for Extra Help generally do not pay a Part D late enrollment penalty while receiving it. Compare current drug plans with your own prescriptions, pharmacies and costs.
Official source: SSA: Apply for Extra Help ↗ · Medicare: Compare plans ↗