Medicare Enrollment Penalty Calculator

Calculate the permanent Medicare Part B and Part D late enrollment penalties based on how long you delayed signing up.

Results

Visualization

How It Works

Medicare charges permanent penalties for late enrollment in Part B and Part D. These penalties are added to your monthly premium for as long as you have Medicare, making them extremely costly over time.

The Formula

Part B Penalty = 10% × Base Premium for each full 12-month period delayed
Part D Penalty = 1% × National Avg Premium × months without creditable coverage

Variables

  • B Delay — Full 12-month periods you could have had Part B but didn't
  • D Delay — Months without creditable prescription drug coverage

Example

12-month Part B delay: 10% penalty = $18.50/month extra. 24-month Part D delay: 24 × 1% × $34.70 = $8.33/month extra. Total: $26.83/month = $322/year forever.

Tips

  • These penalties are PERMANENT — they last as long as you have Medicare.
  • If you have employer coverage, you may qualify for a Special Enrollment Period to avoid penalties.
  • The Part B penalty increases 10% for each full 12-month period you could have enrolled but didn't.
  • Get a letter from your employer confirming creditable coverage to avoid Part D penalties.
  • If you turn 65 and are still working with employer coverage, you generally don't need to enroll yet.