How is the penalty calculated?
| Full years you waited | Penalty | Extra per month | Total Part B premium |
|---|---|---|---|
| 1 year | 10% | $20.29 | $223.19 |
| 2 years | 20% | $40.58 | $243.48 |
| 3 years | 30% | $60.87 | $263.77 |
The penalty is 10% of the standard Part B premium for each full 12-month period you could have had Part B but did not. Medicare's own example: if you waited 2 full years and did not qualify for a special enrollment period, you pay a 20% penalty. With the 2026 standard premium of $202.90, that adds $40.58 a month for a total of $243.48 before any income-related surcharge.
The penalty is a percentage of the standard premium, so it changes when the premium changes. You may also pay a higher premium because of your income.
How can I avoid it?
- Sign up during your Initial Enrollment Period, the seven months around your 65th birthday.
- If you or your spouse are still working and have coverage from that employer, you can usually delay Part B without a penalty and sign up during a special enrollment period when the work or coverage ends.
- If you qualify for a Medicare Savings Program, you generally do not pay a Part B penalty.
The special enrollment period after work-based coverage lasts eight months, starting the month the employment or the coverage ends, whichever is first. COBRA and retiree coverage do not count as work-based coverage for this purpose, so ask Social Security or a licensed agent before you rely on them.
What if I already missed the window?
You can sign up during the General Enrollment Period, which runs January 1 to March 31 each year, and coverage starts the month after you sign up. The penalty applies for as long as you have Part B. Ask whether you qualify for a Medicare Savings Program through your state, because that can pay the premium and remove the penalty.
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