You can cancel Part B, but you need to know the timing and the consequences before you do

To cancel Medicare Part B, you contact Social Security directly — either by phone, in person at a local office, or by mail. The process itself takes a few minutes, but the real work is understanding when you can cancel without penalty and what happens to your coverage if you do. Most people who want to cancel Part B fall into one of two situations: they have employer coverage that makes Part B redundant, or they want to drop it to lower their premiums. The rules are different for each.

Part B covers doctor visits, outpatient care, and medical equipment. If you cancel it, you lose that coverage. You keep Part A (hospital insurance) unless you cancel that separately. The penalty for cancelling Part B and then re-enrolling later can be permanent — an extra 10 percent added to your premium for each year you were without it. That penalty sticks with you for life. So before you call Social Security, make sure you understand whether you actually need to cancel or whether another option exists.

Key Takeaways

  • You cancel Part B by contacting Social Security by phone at 1-800-772-1213, in person at a local office, or by mail with Form CMS-1763.
  • If you have group health insurance through an employer or union, you can cancel Part B without penalty as long as you enroll back within eight months of losing that coverage.
  • If you cancel Part B for any other reason, you will pay a permanent 10 percent premium increase for each year you were without it when you re-enroll.
  • Your cancellation takes effect on the first day of the month after Social Security receives your request, so timing your request matters if you want to avoid paying for a month you do not use.
  • If you have both Part B and a Medigap policy, cancelling Part B usually means your Medigap coverage ends too, and you may not be able to re-enroll in the same plan later.

When you can cancel Part B without a lifetime penalty

You can cancel Part B without facing a permanent penalty if you have group health insurance through your current employer or union. This includes coverage from your own job, your spouse's job, or a retiree health plan. The key word is "current" — the coverage has to be active right now, not something you had in the past.

If you have employer coverage, you can cancel Part B and avoid the penalty as long as you re-enroll within eight months of the day your employer coverage ends. That eight-month window is your safety net. If you lose the job or the coverage ends and you wait nine months to re-enroll, the penalty applies. So if your employer coverage ends on March 15, you have until November 15 to sign back up for Part B penalty-free.

You do not need to cancel Part B to use employer coverage instead — you can keep both. But if your employer plan is primary and Part B is secondary, you may want to cancel Part B to stop paying the monthly premium. Before you do, check with your employer's benefits office about whether cancelling Part B affects your coverage or your employer's obligation to coordinate benefits.

The permanent penalty if you cancel for other reasons

If you cancel Part B for any reason other than having group health insurance, you will pay a 10 percent increase to your Part B premium for each full year you were without it. This penalty is permanent — it does not go away after a few years. If you cancel Part B at age 65 and do not re-enroll until age 72, that is seven years without coverage. Your penalty would be 70 percent added to whatever the standard Part B premium is at the time you re-enroll.

The penalty applies even if you had other insurance during the time you were without Part B. It does not matter if you had a private plan, coverage through a spouse, or anything else. The rule is straightforward: if you were not enrolled in Part B and you did not have group health insurance, the penalty applies when you come back.

Some people cancel Part B thinking they will re-enroll during the next General Enrollment Period (January 1 to March 31 each year). That is possible, but the penalty starts accruing when ready. Do not cancel Part B unless you are certain you will not need it, or unless you have employer coverage to fall back on.

How to request cancellation through Social Security

Contact Social Security using one of three methods. By phone, call 1-800-772-1213 (TTY 1-877-486-2048). You can speak to a representative Monday through Friday, 7 a.m. to 7 p.m. Eastern time. Tell them you want to cancel Part B and they will walk you through the process. They will ask for your Medicare number and confirm your identity.

In person, visit your local Social Security office. You can find the address and hours on ssa.gov by entering your zip code. Bring your Medicare card and a photo ID. The staff will complete the cancellation request on the spot.

By mail, fill out Form CMS-1763 (Request for Change in Medicare Enrollment), which you can read from cms.gov or request by calling 1-800-MEDICARE. Sign and date the form, then mail it to the address listed on the form. Keep a copy for your records. Cancellation by mail takes longer — allow two to three weeks for processing.

When your cancellation takes effect and what to do about other coverage

Your Part B cancellation takes effect on the first day of the month after Social Security receives your request. If you call on March 15, your cancellation is effective April 1. If you mail the form and it arrives on March 20, your cancellation is effective April 1. This matters because you will still owe the Part B premium for any month in which you are enrolled, even if you only use it for one day.

If you have a Medigap policy (supplemental insurance), cancelling Part B usually ends your Medigap coverage too. Some Medigap insurers will let you keep the policy if you have other primary coverage, but most will not. Call your Medigap insurer before you cancel Part B to ask what happens to your policy. If your Medigap coverage ends, you may not be able to re-enroll in the same plan later without going through medical underwriting, which could mean higher premiums or denial based on pre-existing conditions.

If you have Medicare Advantage (Part C), you cannot have Part B and Part C at the same time — Part C includes Part B coverage. If you are in a Medicare Advantage plan and you cancel Part B, you will automatically be disenrolled from the Advantage plan. You will revert to Original Medicare (Part A only) unless you enroll in a new Advantage plan or a Medigap policy.

What to do if you cancel Part B and then change your mind

If you cancel Part B and realize you made a mistake, you can re-enroll, but the timing and the penalty depend on why you cancelled. If you had employer coverage when you cancelled and you lost that coverage, you have eight months to re-enroll without penalty. Contact Social Security using the same methods listed above — by phone, in person, or by mail with Form CMS-1763.

If you cancelled for any other reason, you can re-enroll during the General Enrollment Period (January 1 to March 31). Your coverage will start July 1 of that year. The 10 percent penalty will explore for each year you were without Part B. There is no way to avoid the penalty once you have cancelled without employer coverage as your reason.

If you need Part B coverage before the next General Enrollment Period and you do not have employer coverage, you are out of luck. You cannot enroll outside of the enrollment windows unless you have a may have access to life event (like losing employer coverage or moving to a new state). Plan ahead to avoid this situation.

Common mistakes to avoid when cancelling Part B

Do not assume that cancelling Part B will lower your overall costs. If you have a Medigap policy, losing Part B means losing Medigap too, and you may end up paying more for replacement coverage later. If you have Medicare Advantage, cancelling Part B disenrolls you from the plan, which could leave you with gaps in coverage. Run the numbers with your insurance broker or your state's Health Insurance Counseling and Advocacy Program (HICAP) before you cancel.

Do not cancel Part B thinking you can re-enroll anytime during the year. You can only re-enroll during the General Enrollment Period (January 1 to March 31) unless you have a may have access to event. If you cancel in June and change your mind in September, you will have to wait until January to re-enroll, and your coverage will not start until July of the following year.

Do not forget to notify your doctors and hospitals that you are cancelling Part B. They need to know so they can stop billing Medicare and adjust their records. If you have standing orders for regular care, make sure those are cancelled too.

Frequently Asked Questions

Can I cancel Part B but keep Part A?

Yes. Part A and Part B are separate. You can cancel Part B and keep Part A (hospital insurance) without any problem. You will still have coverage for hospital stays, skilled nursing facility care, and hospice. You just will not have coverage for doctor visits or outpatient care.

What happens to my Part B premium if I cancel?

You stop paying the monthly Part B premium once your cancellation takes effect on the first of the month. However, you are responsible for any premium owed for months in which you were enrolled. If you cancel effective April 1, you owe the March premium but not the April premium.

If I have employer coverage, do I have to cancel Part B?

No. You can keep both Part B and employer coverage. Part B will be secondary, meaning your employer plan pays first. Some people keep Part B for the extra coverage; others cancel it to save the premium. There is no rule requiring you to cancel.

Can I cancel Part B over the phone and have it take effect when ready?

No. Even if you cancel by phone, the cancellation takes effect on the first day of the month after Social Security receives your request. There is no way to make it effective the same day or the same week.

Will I lose my Medicare number if I cancel Part B?

No. Your Medicare number stays with you. If you re-enroll in Part B later, you will use the same number. Cancelling Part B does not affect your Medicare identity or your Part A coverage.