Medicare Part B Late Enrollment Penalty Cost Calculator

Estimate how costly a late Medicare Part B enrollment becomes over time. Enter how many months you delayed signing up and how long you expect to keep Part B to see the penalty rate applied to your premium, the first-year surcharge, and the lifetime dollars forfeited as premiums rise.

Count the full months you went without Part B after your initial enrollment window closed.
How many years you anticipate staying enrolled in Medicare Part B once coverage begins.
Optional — defaults to the 2024 standard premium of $174.70 when left blank.
Optional — defaults to 2% yearly premium growth if blank. Enter 0 for flat premiums.

For educational estimates only. Confirm actual Medicare premiums, penalties, and enrollment deadlines with Social Security or a licensed benefits counselor.

Examples

  • Example 1 — 24-month delay, 20 years on Part B, premium left at $174.70, 2% growth ⇒ Penalty rate applied: 20.00% | First-year penalty: $419.28 | Lifetime penalty over 20 years: $10,187.40 | Monthly penalty in year 1: $34.94 | Monthly penalty by year 10: $41.76 | Monthly penalty in final year: $50.90
  • Example 2 — 60-month delay, 15 years on Part B, $180.00 premium, 3% growth ⇒ Penalty rate applied: 50.00% | First-year penalty: $1,080.00 | Lifetime penalty over 15 years: $20,086.83 | Monthly penalty in year 1: $90.00 | Monthly penalty by year 10: $117.43 | Monthly penalty in final year: $136.13

FAQ

Does the calculator cap the penalty at the annual premium?

No. Medicare penalties are uncapped and scale with premium increases. The calculator compounds the surcharge alongside your growth assumption to show the cumulative impact.

How should I handle income-related surcharges?

IRMAA surcharges apply on top of the penalty. Enter the higher premium you actually pay (standard premium plus IRMAA) if you want to model the true cash impact.

Can I model a future enrollment change?

Yes. Adjust the years-on-Part-B field to represent how long you plan to keep Medicare after enrolling, even if you only need a short-term projection.

Additional Information

  • Medicare adds a 10% premium surcharge for each full 12-month period you delay Part B after losing creditable coverage.
  • The penalty is permanent and rises with future standard premium increases because it multiplies whatever the base premium is each year.
  • Premium growth defaults to 2% annually to mirror recent Medicare trustees projections but can be adjusted for personal forecasts.
  • If you delay fewer than 12 months, no late enrollment penalty is assessed.

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