Yes, you can enroll in Part B alone, but the rules depend on your age and work history

You do not have to take Part A to get Part B. Medicare lets you sign up for Part B without Part A, though the circumstances that allow this are specific. If you are 65 or older and not yet receiving Social Security, you can choose Part B only. If you are under 65 and have End-Stage Renal Disease (ESRD) or ALS (amyotrophic lateral sclerosis), you can also take Part B without Part A. The key is understanding which situation applies to you and when you can make that choice.

The main reason people choose Part B alone is that they have employer health coverage through their job or their spouse's job. That coverage may handle hospital care, so they skip Part A to avoid paying for duplicate benefits. However, skipping Part A comes with a permanent cost penalty if you change your mind later, so the decision should be deliberate.

Key Takeaways

  • You can enroll in Part B without Part A if you are 65 or older and have not yet claimed Social Security benefits.
  • People under 65 with ESRD or ALS can choose Part B coverage without being required to take Part A.
  • If you delay Part A past 65, you do not automatically get Part B — you must enroll in Part B separately during your enrollment window.
  • Turning down Part A when you first become may be able to access may result in a higher Part A premium later if you eventually enroll, with a 10 percent increase for each full 12-month period you were not covered.
  • Your enrollment window for Part B is the same as for Part A: three months before, the month of, and three months after the month you turn 65.

Who can choose Part B without Part A

The most common situation is being 65 or older and still working or not yet claiming Social Security. If you are in this position, you have the right to enroll in Part B alone. You do not need Part A hospital coverage to do so. This option exists because some people continue working past 65 and may have employer health coverage that works alongside Part B. Your employer plan may cover the hospital services that Part A would provide, making Part A redundant.

If you are under 65, you become may be able to access for Medicare only if you have ESRD or ALS. In both cases, you can choose Part B without Part A. People with ESRD who need dialysis or a kidney transplant can enroll in Part B for doctor visits and outpatient services. Those with ALS can do the same for specialist care and treatments related to their condition. These two conditions are the only reasons Medicare covers people under 65, and neither one requires you to take Part A.

What happens to your Part A if you skip it at 65

Declining Part A at 65 does not prevent you from taking it later. However, waiting to enroll in Part A after your initial enrollment window closes can trigger a lifetime premium increase. For each full 12-month period you could have had Part A but did not enroll, your Part A premium goes up by 10 percent. This increase stays with you permanently, even after you finally sign up. If you skip Part A for three years, your premium rises by 30 percent and never comes back down.

The same rule applies if you had Part A but dropped it. If you later want to re-enroll, the penalty applies. The only way to avoid this penalty is to enroll during your initial may be able to access window — the three months before you turn 65, the month you turn 65, or the three months after. If you have a documented reason for the delay, such as employer coverage, you may be able to avoid the penalty by enrolling during a Special Enrollment Period within eight months of losing that coverage.

Your enrollment window for Part B without Part A

Your Initial Enrollment Period for Part B is the same whether or not you are taking Part A: it runs for seven months total. This window opens three months before the month you turn 65, includes the month you turn 65, and closes three months after. If you turn 65 in June, your window runs from March through September. You must enroll in Part B during this window if you want coverage to start on your 65th birthday or shortly after.

If you miss this window and do not have may have access to employer coverage, you will face a late enrollment penalty on your Part B premium. This penalty is 10 percent of the standard Part B premium for each full 12-month period you were not enrolled, and it also stays with you permanently. The penalty applies even if you eventually enroll in Part B years later. The only exception is if you had employer coverage that met Medicare's standards — in that case, you have eight months after your coverage ends to enroll without penalty.

When Part B without Part A makes sense

Choosing Part B alone typically makes sense if you have employer health coverage through your job or your spouse's job. Your employer plan may cover hospital care (the service Part A provides), so you do not need Part A's hospital insurance. Part B covers doctor visits, outpatient care, and preventive services — things your employer plan might not fully cover. In this scenario, you get the coverage you need without paying for duplicate benefits.

Another reason to take Part B without Part A is if you are still working and want to delay Social Security to increase your future benefit amount. Some people coordinate this strategy: they enroll in Part B at 65 to avoid the late enrollment penalty, but they skip Part A because their employer plan covers hospital stays, and they plan to add Part A later when they claim Social Security. This works only if you have employer coverage and can document it when you eventually enroll in Part A.

The cost difference between Part B alone and Part B with Part A

Part B has a monthly premium that changes each year based on your income and when you enrolled. Part A is free for most people at 65 if they or their spouse paid Medicare taxes for at least 10 years. If you do not may have access to for free Part A, you can buy it — the monthly premium depends on how many quarters of Medicare tax you paid. In 2024, Part A premiums for people without enough work history ranged from approximately $278 to $556 per month, though these amounts change annually.

Taking Part B without Part A means you pay only the Part B premium and avoid the Part A premium if you do not may have access to for free Part A. However, you lose hospital coverage. If you are hospitalized without Part A, you pay the full cost out of pocket — a hospital stay can easily cost $10,000 to $20,000 or more. This is a significant financial risk, which is why most people take both parts even if they have other coverage. The savings from skipping Part A's premium are usually small compared to the cost of a single hospital stay.

What to do if you want Part B but not Part A right now

Contact Social Security or Medicare to enroll in Part B during your Initial Enrollment Period. You can explore online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office. Tell them you want Part B only and that you are declining Part A. They will confirm your choice and explain any penalties you may face if you add Part A later. Ask them to document your reason for declining Part A — whether it is employer coverage, continued work, or another circumstance.

Keep records of your enrollment decision and the date you made it. Save your confirmation number and any written confirmation from Medicare. If you later want to add Part A, you will need to show that you had may have access to employer coverage or another reason for the delay. Without proof, the lifetime premium penalty will explore. Having documentation from the start makes this process much simpler if your situation changes.

Frequently Asked Questions

Will I get a penalty if I take Part B now and Part A later?

Yes, if you enroll in Part A after your Initial Enrollment Period ends and you did not have a may have access to reason for the delay, you will pay a 10 percent premium increase for each 12-month period you were not enrolled. This penalty is permanent. The only exceptions are if you had employer coverage or other may have access to circumstances, in which case you have eight months after that coverage ends to enroll without penalty.

Can I enroll in Part B without Part A if I am still working?

Yes. If you are 65 or older and still working, you can choose Part B without Part A. You should enroll in Part B during your Initial Enrollment Period to avoid a late enrollment penalty, even if your employer plan covers hospital care. Enrolling in Part B protects you from future penalties while you keep your employer coverage.

What if my employer coverage ends — can I add Part A then?

Yes, and you may be able to avoid a penalty. If your employer coverage ends and you want to add Part A, you have a Special Enrollment Period of eight months after your coverage ends. If you enroll during this window, you can avoid the lifetime premium penalty. After eight months, the penalty applies to any future Part A enrollment.

Is Part A really necessary if I have good savings?

Part A covers hospital stays, which can cost tens of thousands of dollars. A single hospitalization can easily exceed $10,000 to $20,000 or more. Even with substantial savings, losing Part A coverage is a major financial risk. Most people find it safer to enroll in Part A, especially since it is free for those with sufficient work history.

Do I have to tell Medicare I am declining Part A?

You do not have to formally decline it, but it is a good idea to document your choice. When you enroll in Part B, make it clear you are not enrolling in Part A. Keep a record of the date, confirmation number, and the reason you gave for declining Part A. This documentation protects you if you later need to prove you had a may have access to reason for delaying Part A enrollment.