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Medicare Part B late enrollment penalty

A Part B penalty lasts for life. Make sure yours is right, or never get one.

Social Security's own auditors found about 12,000 people charged roughly $12 million in Part B penalties they didn't owe. If you're paying one, check the math in two minutes. If your job coverage is ending, get your exact sign-up dates so you never pay one.

  • 10% more for every full year, for life
  • ~1 in 9 late enrollments audited were processed wrong
  • 8 months to sign up after job coverage ends
1 · About you
2 · Your Part B sign-up and penalty

Use the Part B amount before any income surcharge (IRMAA) or plan giveback. Your penalty letter or the yearly Social Security benefit letter shows it.

3 · Job-based health coverage after 65

Only coverage while you or your spouse were still working counts. COBRA, retiree plans, VA and Marketplace plans don't.

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What you'll see

Paying a penalty: the penalty you should be charged, month by month, and what you're overpaying each year.

Coverage ending: the exact day your 8-month Part B window closes, your Part D deadline, and what missing it would cost.

The $19 kit adds a filled-in appeal (Form SSA-561-U2) or sign-up (CMS-40B and CMS-L564), the letters to send, the evidence list and calendar reminders.

How the penalty works

10% of the standard premium for every full 12 months you could have had Part B and didn't, added to your premium for as long as you have Part B. Months covered by a current job's plan don't count.

Where it goes wrong

Job coverage months that never got excluded, special enrollments processed as late ones, and pre-2023 counting rules applied to new sign-ups. The Inspector General found errors in 23 of 200 cases.

How to fix it

Ask Social Security to reconsider within 60 days of the letter, on Form SSA-561-U2, with proof of your job coverage. A Medicare Savings Program also removes the penalty entirely.

Part of Letter Desk: free checks for the letters that hit around retirement

IRMAAback

Retired but paying Medicare's income surcharge? Form SSA-44 can lower it.

ClawbackCheck

On an ACA plan before 65? See if you'll repay your 2026 subsidy, and how to avoid it.

All checks

Not sure which letter you got? Start at Letter Desk.