Part B late enrollment penalty
If you do not sign up for Part B when you are first eligible and you do not qualify for a Special Enrollment Period, your Part B premium may increase 10% for each 12-month period you were eligible but not enrolled. That surcharge can last as long as you have Part B.
Part D late enrollment penalty
If you go 63 days or more without creditable prescription coverage after you are eligible, you may pay a Part D penalty for as long as you have Part D. The amount is based on how long you went without coverage.
How to reduce the risk
Know your IEP, confirm whether employer coverage is creditable, and do not assume a Marketplace plan is a substitute for Medicare after 65. If you already have a penalty, an advisor can still help you understand current options — the penalty itself is generally administered by Medicare or the plan.
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2026 figures
Part B late enrollment penalty
Estimate the 10% Part B surcharge for each full 12-month delay.
2026 figures
Part D late enrollment penalty
Estimate the monthly Part D penalty using the 2026 national base premium.