Enrolling in Medicare

What is the Medicare late enrollment penalty?

Medicare can add a permanent surcharge to your premium if you sign up late without other qualifying coverage. The Part B penalty adds 10% for each full year you delayed, and the Part D penalty grows the longer you go without creditable drug coverage. Enrolling on time, or keeping creditable coverage, avoids both.

Reviewed by Scott Stafford, Licensed Insurance Agent

Last updated June 21, 2026

The Part B penalty

If you don't sign up for Part B when first eligible and don't have active employer coverage, the penalty adds 10% to your Part B premium for each full 12-month period you could have had it but didn't. It's not a one-time fee — it's added to your premium for as long as you have Part B.

The Part D penalty

If you go 63 days or more without Part D or other creditable drug coverage after your Initial Enrollment Period, Medicare can add a penalty to your Part D premium. It's calculated from how many months you went without coverage and grows the longer you wait. Like the Part B penalty, it's generally permanent.

How to avoid both

The simplest path: enroll when you're first eligible. If you're delaying because you have active employer coverage, that coverage protects you — just enroll within your Special Enrollment Period when it ends. For drugs, make sure any coverage you keep is "creditable" (at least as good as Part D); your plan can tell you in writing.

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