Quick answer
If you don’t sign up for Medicare when you’re first eligible and you don’t have qualifying coverage, you can owe a late enrollment penalty. The Part B penalty adds 10% to your premium for each full year you went without it, usually for as long as you have Part B. The Part D penalty adds 1% of a national base premium for every month you went without creditable drug coverage, also for life. Part A only carries a penalty if you have to buy it. Current coverage from a job, yours or your spouse’s, at an employer with 20 or more workers usually lets you delay without a penalty.
Key takeaways
- The Part B penalty is 10% of the standard premium for each full 12-month period you could have had Part B but didn’t, and it usually lasts as long as you have Part B.
- The Part D penalty is 1% of the national base beneficiary premium ($38.99 in 2026, $41.33 in 2027) for each full month without creditable drug coverage, recalculated every year.
- COBRA and retiree coverage don’t count as current job-based coverage, so they won’t protect you from the Part B penalty.
- If you lose job-based coverage from current work, you get 8 months to sign up for Part B without a penalty, even if you take COBRA.
- A Medicare Savings Program erases the Part B penalty, and Extra Help erases the Part D penalty.
On this page
How each penalty works
| Part | When you can owe a penalty | How big it is | How long it lasts |
|---|---|---|---|
| Part A | Only if you have to buy Part A and don’t sign up when first eligible | Premium goes up 10% | Twice the number of years you delayed |
| Part B | You didn’t sign up when first eligible and had no qualifying job-based coverage | 10% of the standard premium per full year you went without it | Usually as long as you have Part B |
| Part D | You went 63 or more days in a row without Medicare drug coverage or other creditable drug coverage | 1% of the national base premium per uncovered month | As long as you have Part D |
The Part B penalty
Medicare’s own example: if you go 24 months past your deadline with no special enrollment period, your Part B premium carries a 20% penalty (10% for each of the two full years). In 2026, that’s about $40.60 on top of the $202.90 standard premium, or about $243.50 a month. Since the penalty is a percentage of the standard premium, the dollar amount goes up whenever the premium does. If your income is high enough to owe IRMAA, that’s charged separately and stacks on top. See the Part B premium and IRMAA brackets.
The usual reason people get hit with this penalty is thinking some other coverage lets them wait. For Part B, only group coverage based on current work, yours or your spouse’s, counts, and only if the employer has 20 or more employees. COBRA doesn’t count. Neither does retiree coverage, a Marketplace plan or a plan you buy on your own. If you’re 65 or older and on one of those, sign up for Part B.
When job-based coverage from current work ends, or the job ends, whichever comes first, you have 8 months to sign up for Part B without a penalty. That clock starts even if you choose COBRA. See COBRA health insurance and working past 65 for how this plays out.
The Part D penalty
You can owe a Part D penalty if, after your initial enrollment period ends, you go 63 or more days in a row without Medicare drug coverage or other creditable drug coverage. Creditable means coverage expected to pay, on average, at least as much as standard Medicare drug coverage. Employers and unions that offer drug coverage have to tell Medicare-eligible members each year whether it’s creditable, usually in a notice sent before October 15. Keep those notices.
The penalty is 1% of the national base beneficiary premium times the number of full months you went without coverage, rounded to the nearest 10 cents. Say you went 24 months without coverage. In 2026 your penalty would be 24% of $38.99, or about $9.40 a month, added to whatever your plan charges. In 2027, with a base premium of $41.33, the same 24 months works out to about $9.90 a month. The number of months never changes, but the dollar amount is recalculated every year.
Be careful with news stories that quote the “average” Part D premium. The penalty uses the national base beneficiary premium, which is a different number.
The Part A penalty
Most people get Part A without a premium because they or a spouse worked and paid Medicare taxes long enough, usually 10 years. If you have to buy Part A (it costs $311 or $565 a month in 2026, depending on your work history) and you don’t sign up when you’re first eligible, your premium can go up 10%. You’d pay the higher premium for twice the number of years you waited. Two years late means four years of the higher premium.
How to get a penalty reduced or removed
- Medicare Savings Programs: if you qualify for one, your Part B penalty goes away. These programs are for people with limited income and savings. See who is eligible for Medicare and health insurance for the elderly.
- Extra Help: if you get Extra Help paying for drug coverage, you don’t owe a Part D penalty.
- Appeal a Part B penalty: follow the instructions on your penalty notice, or use Social Security’s request for reconsideration. You generally have 60 days from the notice. Good grounds include proof that you had qualifying job-based coverage the whole time or that the penalty was miscalculated. Employer letters, W-2s and pay stubs showing premium deductions, and insurance cards all help. Not knowing the rules usually isn’t enough.
- Equitable relief: if you missed signing up because a Social Security or Medicare employee gave you wrong information or didn’t act, you can ask Social Security in writing to fix your enrollment or remove the penalty. This doesn’t apply to bad advice from an employer or an insurance agent.
Keep paying the penalty while an appeal is pending. If you win, you get the money back. For plan choices once you’re enrolled, see Medicare Advantage vs. Medigap.
More on Medicare: the Part B premium and IRMAA, working past 65, Medigap Plan G vs. Plan N, Medicare Advantage vs. Medigap, Medicare open enrollment and who is eligible for Medicare.
Need coverage until your Medicare starts? Compare plans by ZIP code.
Frequently asked questions
How much is the Medicare Part B late penalty?
It’s 10% of the standard Part B premium for each full 12-month period you could have had Part B but didn’t. Two full years late means a 20% surcharge, about $40.60 a month in 2026.
Is the Part B penalty permanent?
For most people, yes. It lasts as long as you have Part B. The main exception is getting into a Medicare Savings Program, which removes it.
Does COBRA count as coverage for delaying Medicare?
No. COBRA doesn’t count as coverage from current work, so it won’t protect you from the Part B penalty. Your 8-month window to sign up starts when your job or job-based coverage ends, even if you take COBRA.
How is the Part D penalty calculated?
Take 1% of the national base beneficiary premium ($38.99 in 2026) and multiply it by the number of full months you went without creditable drug coverage. That amount is added to your monthly Part D premium and recalculated every year.
Sources
This article is general information, not legal or financial advice. Penalty rules have exceptions, so check your situation with Social Security or your State Health Insurance Assistance Program (SHIP) before you delay enrolling. Last reviewed September 2026.