Updated: Sep 9, 2026
Key Takeaways
- The penalty is generally 10% for each full 12-month period that counts.
- At a 20% penalty, the 2026 standard premium totals $243.50 after Medicare’s rounding.
- Employment coverage, Special Enrollment Periods, and assistance can change whether a penalty applies.
Calculate Your Estimate
Use only months that count toward a late-enrollment penalty.
Enter whole months confirmed to count under Medicare rules. Do not include exempt months or assume all time without Part B counts.
Estimated monthly premium plus penalty
$202.90
- Full 12-month periods
- 0
- Penalty rate
- 0%
Penalty before rounding: $0.00. The combined total is rounded to the nearest $0.10.
Excludes income-related adjustments and other billing changes. Future annual premiums may change.
See Medicare’s penalty rules and rounding example. This tool estimates the amount; Social Security determines whether a penalty applies.
2026 penalty examples
Assumes the full delay counts, with no exemption or income-related adjustment.
Use months that actually count
Enter the months of delay that count under Medicare's rules, not simply every month you were without Part B. An Initial Enrollment Period, qualifying current-employment coverage, a Special Enrollment Period, or assistance through a Medicare Savings Program can affect the outcome. Confirm the count with Social Security if your history is uncertain.
The tool estimates the standard premium plus late-enrollment penalty. It does not determine eligibility, appeal rights, income-related adjustments, or your final bill. An employer-coverage checkbox cannot establish an exemption on its own.
The 2026 calculation
- Divide counted months by 12 and keep only complete periods.
- Multiply complete periods by 10%.
- Apply that percentage to the standard Part B premium.
- Add the premium and penalty, then round the total to the nearest $0.10 as Medicare illustrates.
| Counted delay | Penalty rate | 2026 monthly total |
|---|---|---|
| 0–11 months | 0% | $202.90 |
| 12–23 months | 10% | $223.20 |
| 24–35 months | 20% | $243.50 |
For 24 counted months, $202.90 × 20% = $40.58. Adding the base gives $243.48, which rounds to $243.50. The rounded increase over the base is $40.60 monthly, or $487.20 for 12 months at the same premium. Future annual premiums can change; this is not a lifetime cost forecast.
Check exceptions before relying on the estimate
Coverage based on your or your spouse's current employment may support a Special Enrollment Period. Timing and the type of coverage matter. COBRA and retiree coverage do not extend the usual eight-month current-employment Part B window.
Medicare Savings Programs can affect penalty obligations. People who had Medicare before 65 may also have a new enrollment opportunity at 65. Ask Medicare or Social Security which rule applies to your circumstances rather than assuming every delay creates a lifelong charge.
If you received a penalty notice
Compare the notice with your enrollment dates and employer records. Follow the notice's instructions to request review or appeal within its deadline. Keep copies of evidence and confirmations.
The penalty generally continues for as long as you have Part B unless an applicable exception or correction changes it. See enrollment deadlines and Medicare's official penalty example for the rules behind this estimate.
Frequently Asked Questions
What is a 20% Part B penalty in 2026?
Does all time without Part B count?
ARTICLE SOURCES
Read our editorial policy for our sourcing standards.
- Medicare. Avoid late enrollment penalties.
- Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B premiums and deductibles.
- Medicare. When can I sign up for Medicare?.
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