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Penalties
Two formulas, both published by Medicare. Move the slider to see how the count works. Nothing here is a decision about anyone — months covered by a current job or by creditable drug coverage do not count.
Count the full 12-month periods someone could have had Part B but did not — and was not covered by a current job. Each one adds 10 % to the monthly premium.
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0 full 12-month period(s). On the 2026 standard premium of $202.90, the formula would add about $0.00 a month. Social Security does the actual count.
It lasts for as long as Part B does — usually for life.
After your first enrollment period, a gap of 63 consecutive days or more without Part D or other creditable drug coverage can lead to a late penalty. People who get Extra Help do not pay this penalty.
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On the 2026 base premium of $38.99, the formula would add about $0.00 a month to whatever the chosen plan charges. Medicare does the actual count.
When a Part D penalty applies, Medicare counts full uncovered months at 1% of the national base premium and rounds the penalty to the nearest 10 cents. It generally lasts while you have Part D; Extra Help is an exception.
Medicare.gov: penalty formulas, premium figures and exceptions ↗
These formulas illustrate possible penalties (figures checked 2026-09-09). Qualifying current-employment coverage and Special Enrollment Periods affect Part B. Creditable drug coverage and Extra Help affect Part D. Medicare Savings Programs can also affect Part B penalties. Ask Social Security or Medicare to confirm your situation.
For every full 12-month period you could have had Part B but did not — and were not covered by a current job — the monthly premium goes up by 10 %. It stays that way for as long as you have Part B.
Source: Medicare.gov — Avoid late enrollment penalties · In effect since 1966-01-01 · Last checked 2026-09-06
When a Part D penalty applies, Medicare counts full uncovered months at 1% of the national base premium and rounds the penalty to the nearest 10 cents. It generally lasts while you have Part D; Extra Help is an exception.
Source: Medicare.gov — Part D costs and the late enrollment penalty · In effect since 2006-01-01 · Last checked 2026-09-06
If the first window closed and no special window applies, you can sign up for Part B between January 1 and March 31 each year. Coverage starts the first day of the month after you sign up.
Source: Medicare.gov — When does Medicare coverage start? · In effect since 2023-01-01 · Last checked 2026-09-06
