How Medicare Penalties Work
Medicare.gov describes late enrollment penalties in three plain points. They are added to your monthly premium. They are not a one-time fee. And they are usually charged for as long as you have that type of coverage, which for most people means for life. The Part A penalty is the exception, with a time limit.
Penalties also grow with time: the longer you go without coverage when you could have had it, the bigger the percentage. Because they are calculated from each year’s premium, the dollar amount usually rises as premiums rise.
The Part B Late Enrollment Penalty
If you do not sign up for Part B when first eligible, and you do not qualify for a Special Enrollment Period, you pay an extra 10% of the standard Part B premium for each full 12-month period you could have had Part B but did not.
Medicare.gov’s 2026 example shows the math:
| 2026 standard Part B premium | $202.90 |
| Penalty: 2 full 12-month periods × 10% = 20% | $40.58 |
| Total, rounded to the nearest $0.10 | $243.50 a month |
Higher-income enrollees can pay more than that through IRMAA; see our IRMAA guide. Medicare.gov also notes you generally will not pay a Part B penalty if you enroll in a Medicare Savings Program.
Signing up late also means waiting. Outside a Special Enrollment Period, you can only sign up during the General Enrollment Period, January 1 to March 31, with coverage starting the month after you sign up.
The Part D Late Enrollment Penalty
You may owe a Part D penalty if, after your Initial Enrollment Period ends, you go 63 days or more in a row without Part D or other creditable drug coverage. Creditable means drug coverage that is similar in value to Medicare Part D. Employers and plans tell you each year whether yours is creditable.
The penalty is 1% of the national base beneficiary premium for each full month without coverage. Medicare.gov’s 2026 example:
| National base beneficiary premium | $38.99 (2026) · $41.33 (2027) |
| Penalty percentage: 14 months × 1% | 14% |
| 2026 monthly penalty: $38.99 × 0.14 = $5.46, rounded | $5.50 |
The penalty is added to your plan premium for as long as you have Medicare drug coverage, even if you switch plans. Since the base premium changes each year, so does the penalty. People who qualify for Extra Help do not pay it.
The Part A Late Enrollment Penalty
Most people never face this one, because most people get Part A premium-free. It applies only if you have to buy Part A (in 2026, $311 or $565 a month, depending on work history) and you do not buy it when first eligible.
The premium goes up 10%, and you pay the higher premium for twice the number of years you could have had Part A but did not sign up. Medicare.gov’s example: eligible for 2 years without signing up means paying the higher premium for 4 years. The Part A premium check helps you see whether you are likely to owe a Part A premium in the first place.
How to Avoid All Three
- Enroll during your Initial Enrollment Period, the 7 months around your 65th-birthday month, unless you have qualifying coverage. Our turning 65 checklist lays out the steps.
- Know whether your job coverage counts. Group coverage based on current work, yours or a spouse’s, generally lets you delay Part B without a penalty, and you get 8 months to sign up after it ends. COBRA and retiree coverage do not count as current-work coverage and do not extend that window. Details in working past 65.
- Keep creditable coverage notices for your drug coverage. They are your evidence if a Part D penalty is ever applied by mistake.
- Consider a low-premium drug plan if you have no other drug coverage. Medicare.gov suggests this even if you take few drugs now, to avoid the penalty.
- Check for help programs. Extra Help removes the Part D penalty, and Medicare Savings Programs can affect the Part B penalty.
The Medicare penalty calculator estimates what a delay would cost you, using the published figures above.
If You Already Have a Penalty
After you join a drug plan, the plan tells you if you owe a Part D penalty and what your premium will be. If you disagree, for example because you did have creditable coverage, Medicare.gov explains how to ask for a review; gather your old coverage notices first. For Part B, if you believe you should have had a Special Enrollment Period, contact Social Security. Some newer Part B Special Enrollment Periods, such as for people who received inaccurate information from an employer or health plan, are requested with form CMS-10797.
Want to see every enrollment window in one place? See our Medicare enrollment periods guide.
Worried you have already missed a window?
Tell us your dates and the coverage you had. We will check whether a Special Enrollment Period applies before you sign up, so you do not pay more than you have to.
Request a free comparison Call 208-350-9933Frequently Asked Questions
How much is the Medicare Part B late enrollment penalty?
The Part B penalty is 10% of the standard Part B premium for each full 12-month period you could have had Part B but did not sign up, and it is usually charged for as long as you have Part B. Medicare.gov’s 2026 example: a 24-month delay means a 20% penalty, for a total monthly premium of $243.50.
How is the Part D penalty calculated?
Medicare multiplies 1% by the number of full months you went without Part D or other creditable drug coverage, then multiplies that by the national base beneficiary premium, which is $38.99 in 2026 and $41.33 in 2027. The result is rounded to the nearest $0.10 and added to your plan premium.
Is the Part A penalty for life too?
No. The Part A penalty only applies to people who have to buy Part A because they do not qualify for premium-free Part A. It raises the premium by 10%, and you pay it for twice the number of years you could have had Part A but did not sign up.
Do I get a penalty if I had insurance from my job?
Usually not, if the coverage counts. For Part B, group health coverage based on your or your spouse’s current work lets you delay without a penalty, and you get an 8-month Special Enrollment Period after it ends. For Part D, the drug coverage must be creditable, meaning similar in value to Medicare Part D.
Can I get a Part D penalty removed?
If you think a Part D late enrollment penalty is wrong, for example because you had creditable coverage, Medicare.gov explains how to ask for a review. Keep the creditable coverage notices your employer or plan sends each year, because they are your proof. People who get Extra Help do not pay a Part D late enrollment penalty.
Related Guides
Coverage pages for this topic: Medicare Advantage · Medicare Supplement · Medicare Part D. Other topics in the Learning Center: Health Insurance (ACA), Life Insurance, Final Expense, Annuities, Long-Term Care, Disability Insurance, Supplemental Health, Short-Term Medical, Travel Insurance.
Sources
- Medicare.gov — Avoid late enrollment penalties
- Medicare.gov — When does Medicare coverage start?
- Medicare.gov — Medicare costs (2026)
- CMS — 2026 Medicare Parts A & B Premiums and Deductibles (fact sheet)
- CMS — Medicare Part D 2027 national average monthly bid amount (base beneficiary premium)
- Medicare.gov — Who pays first (coordination of benefits)
- Medicare.gov — Help with drug costs (Extra Help, 2026 limits)
Figures are labelled with the year they apply to and were checked against the official sources above on the review date. Rules and amounts change; confirm current figures with the agency that publishes them. This guide is general education, not individual advice.