Medicare Supplement Enrollment: When Can You Join or Change Plans?

Healthcare Writer

Updated on March 25th, 2022

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MYTH: You have to wait until November to join a Medicare Supplement plan.

Fact: Most people can join or change Medicare Supplement plans any time.

Thankfully, you can compare and apply for Medicare Supplement plans whenever you want. If possible, you’ll want to apply during your unique Medigap Open Enrollment Period or Medigap Protections Period, also called a guaranteed issue right. During these times, approval is guaranteed at the lowest possible price.

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Best Time To Get Medicare Supplement: Your Open Enrollment Period

Your 6-month Medigap Open Enrollment Period is the easiest time to join or change Medigap plans.

During your Open Enrollment Period, Medicare Supplement providers must:

  1. Offer you any plan they have (“guaranteed enrollment”)
  2. Offer you plans at the most favorable terms (“guaranteed lowest price”).

When Is the Medigap Open Enrollment Period?

When to Apply for Medigap illustration |

There’s no fixed time of the year for everyone to have a Medigap Open Enrollment Period.

The timing of your personal Medigap Open Enrollment Period depends on when you get Medicare Part A and B. Specifically, it begins on the first day of the month that you are both:

  1. 65 years or older AND
  2. covered under Medicare Part B.

Your Medigap Open Enrollment Period then lasts for a total of six months.

How Do You Find Your Medigap Open Enrollment Period?

If you wait until you turn 65 to enroll in Medicare Part B, then your Medigap Open Enrollment starts after you enroll in Part B. Your Open Enrollment Period must begin on the first day of the month.

  • Example A: You’re already 65, and you sign-up for Medicare Part B on June 14.
    • Your Medigap Open Enrollment Period doesn’t start until July 1 and it lasts until December 31.
  • Example B: You’re already 65, you sign-up for Medicare Part B and it begins June 1.
    • This means that your Medigap Open Enrollment Period is from June 1 to November 30.

If you get Medicare Part B before you turn 65, then your Open Enrollment Period starts the first day of the month you turn 65.

  • Example C: You enroll in Medicare Part B when you’re still 64 and in your Initial Enrollment Period. Your birthday is on August 8.
    • This means that your Open Enrollment Period starts August 1 (the first day of the month when you turn 65) and lasts until January 31.

Remember that your Medigap Open Enrollment Period lasts for six months, starting from the first day of the month in which you’re both 65 and enrolled in Medicare Part B.

You Only Have One Medigap Open Enrollment Period

Once your Open Enrollment Period begins, it cannot be replaced or delayed. You should take full advantage of this period’s benefits. Discover which plan suits your needs, then buy Medigap insurance within this six-month window.

You may be used to re-applying for health coverage every year if you bought private health insurance before enrolling in Original Medicare. However, your Medigap Open Enrollment Period only comes once.

Medigap Open Enrollment Deadline

Many people still join a Medicare Supplement after their Open Enrollment Period in which coverage is guaranteed.

If you miss your 6-month open enrollment deadline, many insurers will still offer you coverage. However, insurers will be free to deny your application or charge higher monthly payments. In all cases, Medicare Supplement plans are renewable for life once you’ve enrolled in the plan.

Applying early makes the difference between having affordable coverage for life, or having to jump through hoops for coverage in the future.

What If You’re Not Eligible for Open Enrollment?

If you miss your chance to enroll at age 65, then you don’t have to worry about open enrollment just yet.

For example – if you’re 66 years old but have never enrolled in Medicare Part B because you are currently covered by an employer health plan – then your Medigap Open Enrollment Period has not yet occurred. It will only begin once you leave your group plan and enroll in Medicare Part B.

Get Coverage Outside of Open Enrollment 

You only get one Medigap Open Enrollment Period. But there are other times, depending on the circumstances, when you can qualify for a Medicare Supplement. This is called a guaranteed issue right, also called “Medigap protections.” 

Guaranteed issue rights mean that in certain situations, insurance companies are required to offer you certain Medigap policies. The insurance company also must cover all your pre-existing health conditions and cannot charge more because of these conditions. The guaranteed issue right occurs mostly when you have other health coverage that changes, like you lose your health coverage in certain circumstances. But it can also occur when you try a Medicare Advantage Plan (Part C) during a trial period, change your mind, and then still decide to buy a Medigap policy. 

In the following situations, you have a guaranteed issue right. 

  • Insurance companies must offer a Medicare Supplement, with no medical exclusions, when an insurance company goes bankrupt, doesn’t follow the rules, or you lose coverage through no fault of your own. 
  • You have Original Medicare as well as an employer health plan (including retiree or COBRA coverage), or union coverage, that pays after Medicare pays, and that plan is ending.
  • You decide to disenroll from a Medicare Advantage plan during a 12-month trial period. There are two times this happens.
    • You enroll in a Medicare Advantage plan when initially eligible, at age 65. 
    • You have a Medicare Supplement and drop this coverage to try a Medicare Advantage plan. (You only get this opportunity once.)
  • You have a Medicare Advantage plan and move outside the plan’s service area or the plan stops providing care in your area. 
  • You have Original Medicare and a Medicare SELECT policy, and you move out of the Medicare SELECT policy’s service area.
  • You live in CT, MA, NY, or ME.

Several states, including California, Oregon, and Missouri allow those who already have a Medicare Supplement to change to a plan with the same or lesser benefits. Each state has its own times and rules.

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Free To Apply At Any Time

Both traditional health insurance and Medicare Advantage plans restrict signups to a certain time of the year. Many people assume that this is the case for Medicare Supplement plans, too, but it’s not so.

It’s best to apply during your Medigap Open Enrollment period because there’s no medical underwriting and the lowest-cost guaranteed. However, you can join a Medicare Supplement plan outside of an enrollment period. While enrollment isn’t always guaranteed, Medicare Supplement providers issue policies year-round.  

Same Benefits No Matter When You Apply

Once you’re in, you’re in. The Medigap plan you get outside of your Medigap Open Enrollment Period will have the same coverage and guaranteed renewability for life.

If You Already Have Medicare Advantage

You can switch from Medicare Advantage to Original Medicare and back during the Annual Election Period, more commonly known as the Open Enrollment Period, which lasts from October 15 through December 7. Most people can also move to Original Medicare, Part A and Part B, during the Medicare Advantage Open Enrollment Period from January 1 to March 31. However, getting a Medicare Supplement plan may involve medical underwriting. You’ll want to call to connect with an independent, locally-licensed agent who can help with this process.

Drawbacks To Applying After Open Enrollment

If you miss your Medigap Open Enrollment Period, you may be subject to medical underwriting. This means that your application could be denied by the insurance company offering the plan. Your application could also be accepted at a higher price than you were hoping to spend.

FAQs About Medicare Supplement Enrollment

What Is Medicare Supplement?

Medicare Supplement plans (“Medigap”) work with Original Medicare (Medicare Part A and Part B to limit out-of-pocket costs. Unlike Medicare Advantage programs, these are not replacement plans for Original Medicare.

When you get sick or injured, deductibles and copayments with Original Medicare are harsh. The solution is Medicare Supplement plans. They’re designed by the federal government but sold by private companies.

Medicare Supplement plans are a valuable part of your complete Medicare coverage. These tightly-regulated plans pay the coverage gaps that Original Medicare would otherwise bill to you.

With so many Medicare Supplement providers to choose from, it’s no wonder folks are surprised when they can get Medigap at a competitive price at any age.

You can learn more about Medicare Supplement plans here.

Do You Need to Apply for Medicare Supplement Every Year?

Medicare Supplement plans are guaranteed renewable each year. Simply continue paying your monthly premiums so that your coverage will continue.

In the rare case that your insurer stops offering your plan, you will be informed well in advance. You’ll be able to join any Medicare Supplement plan at the lowest possible rate. Even if you have a plan that’s no longer offered (like Plan J), you’ll be able to buy into that same plan if you can find a carrier who offers it.

When Can You Change Medicare Supplement Plans?

You can join or change Medicare Supplement plans whenever you like. Unless you have a guaranteed issue right, you will need to be accepted by your replacement plan. Your replacement plan does not automatically have to accept you in most cases. You can continue to compare different companies until you find one that meets your needs.

Should You Wait to Apply for Medigap?

You should apply once your Medigap Open Enrollment Period begins. The actual application process is straightforward, but you don’t want to rush into a decision.

You may be healthy when considering whether to enroll, but it’s important to be ready for coverage in case your health condition changes. 

Still, enroll as soon as possible to avoid running into any issues tied to your health. While your Medicare Supplement plan can’t pick and choose which health issues to cover, your plan can delay coverage for conditions that were diagnosed or treated during the six months before you enroll and for up to six months after you enroll. However, your plan cannot delay coverage for pre-existing conditions if you had continuous and comprehensive “creditable coverage” for the six months before you enrolled. And Medicare Part A and Part B will still cover you for those six months.

What If You Have Employer Coverage?

If you or your spouse has group health coverage through a union or employer – and you want to keep that coverage for now – then you will not be penalized for waiting to get Medicare Supplement. 

Monthly Premiums Are Far Less Costly Than Paying Out-Of-Pocket for an Unexpected Medical Issue

As we age, it’s increasingly likely that we will incur very high medical bills. Medigap plans ease this by covering up to 100 percent of common medical expenses – including coinsurance, deductibles, hospice care, and excess charges.

At first glance, you might think that Medicare Supplement paying only 20 percent of costs is a bum deal. Take a closer look, because Medicare Supplement comes into play when you’re faced with astronomical hospital bills. Joining a Medicare Supplement plan is a sound financial decision in its own right. In fact, half of Medicare Supplement enrollees make less than $30,000 per year. 

Of course, no one likes paying monthly premiums, but Medigap benefits are extremely generous. To give a better idea of how much you could save on out-of-pocket costs by purchasing a Medigap plan, here are a few hypothetical situations:

Example A: You accidentally fracture your hip. (Almost 90% of hip fractures happen to people over the age of 65).1

With Original Medicare, you’d be responsible for paying your deductible for your inpatient stay and surgery ($1408 in 2020), plus a $198 deductible and then 20% of everything for your outpatient services, such as the ambulance, physical therapy, and medical equipment.

With different Medigap plans, you would simply pay an annual premium and sometimes a deductible, no matter how high the cost of treatment becomes.

Example B: You have unusual chest pain and make the smart choice to rush to the emergency room. You’re admitted to your local nonprofit hospital and observed for two days.

It turns out to be nothing, but the bills for your inpatient care are off-putting: With just Original Medicare, you would have been on the hook for your deductible of $1408, plus a $198 deductible and then 20% of everything for your outpatient services Under some Medigap plans, your hospital stay would cost you nothing.

How Long Does the Medigap Application Process Take?

You will need basic personal information about yourself and your existing Medicare coverage to apply for a Medicare Supplement policy.

Medicare Supplements can only be sold by licensed insurance agents. These agents are trained to present you with multiple options from different companies. Agents make the process as easy and pressure-free as possible, on the phone or online.

Once you select a specific Medicare Supplement plan, the application process should take less than an hour. It would be a mistake, though, to wait until the last minute to select a plan.

Can You Apply for Medigap If You’re 64 Years Old Or Younger?

Not all states require Medicare Supplement plans to cover people with Medicare who are under age 65. There are 33 states that require insurance companies to offer plans to people under age 65 who otherwise qualify for Medicare because of disability or end-stage renal disease (ESRD).2

ArkansasKentuckyNew Jersey
CaliforniaLouisianaNew York
ColoradoMaineNorth Carolina
GeorgiaMinnesotaSouth Dakota
KansasNew HampshireWisconsin

Rights vary by state, so check with your state insurance department for specifics.

If you live in a state that doesn’t require Medicare Supplement availability for younger people, insurers may still offer you a Medicare Advantage plan.

Can You Get Medicare Supplement If You Have Medicare Advantage?

Medicare Advantage is a private program that combines Medicare Part A and Medicare Part B coverage with additional benefits, like drug coverage. You cannot have both Medigap and Medicare Advantage coverage at once.

You can switch from Medicare Advantage to Original Medicare and back during the Annual Election Period, which lasts from October 15 through December 7.

Year-long Trial Period for Medicare Advantage

Medicare offers trial periods with specific rules, including joining a Medicare Advantage plan when first eligible for Medicare at age 65, and signing up for Original Medicare with a Medigap policy but then switching to a Medicare Advantage plan for the first time. If you have tried Medicare Advantage for less than a year and would prefer to revert to Original Medicare with a Medicare Supplement, then you have guaranteed issue rights and can purchase any Medicare Supplement plan under the most favorable terms.

Can Spouses Get Coverage Under A Medicare Supplement Policy?

Unlike an employer group health plan, Medicare Supplement plans will not cover your spouse or other individuals in your household. They will need to apply on their own for Medigap coverage.

Who Offers Medicare Supplement Plans?

Medicare Supplement plans are designed by the government and sold by private insurance companies. The significant difference between plans of the same letter type (like all Plan Ns) is price. Blue Cross Blue Shield and AARP are some of the popular Medicare Supplement providers which you can price compare on 

Are There Medigap Plan Options In Your Area?

Medicare Supplement availability and rates depend on your state and ZIP code. Medigap plans are standardized lettered Medigap plans, meaning that a Medigap Plan F in Utah offers the same benefits as a Medigap Plan F in Massachusetts.

How Do You Know If You’re Covered By Medicare Supplement?

Once you enroll in a Medigap plan, your insurer will send you materials in the mail. If you have an email account, you may receive immediate confirmation of your coverage.

It’s easy to confuse a Medicare Supplement Plan B with Medicare Part B. To determine whether or not you have a Medicare Supplement plan, check out your insurance card. You’ll likely see the word “Supplement,” also with a “Plan A”, “Plan G”, or another combination of “Plan” and a letter.

Wisconsin, Minnesota, and Massachusetts have their own standardization method. You won’t see Plan G or Plan N in those states. However, their Medicare supplement plans work with Part A and Part B just as with plans in other states. 

How Do You Decide Which Medigap Plan Is The Best One?

There are 10 types of Medigap plans, each with benefits defined by the federal government. Newly eligible beneficiaries cannot purchase Plan C or Plan F. 

Medicare is accepted by most medical professionals, and Medicare Supplement is accepted by anyone who takes Medicare.

Each plan will have pricing and plan documentation available on the web that you can compare. Consider your health needs when deciding which Medicare Supplement plan is right for you.

Medigap BenefitsMedigap Plans*
Part A coinsurance and hospital costs up to an additional 365 days after Medicare benefits are used upYesYesYesYesYesYesYesYesYes Yes
Part B coinsuranceYesYesYesYesYesYes50%75%Yes Yes ****
Blood (first 3 pints)YesYesYesYesYesYes50%75%Yes Yes
Part A hospice care coinsuranceYesYesYesYesYesYes50%75%Yes Yes
Skilled nursing facility care copayNoNoYesYesYesYes50%75%Yes Yes
Part A deductibleNoYesYesYesYesYes50%75%50% Yes
Part B deductibleNoNoYesNoYesNoNoNoNo No
Part B excess chargeNoNoNoNoYesYesNoNoNo No
Foreign travel exchange (up to plan limits)NoNo80%80%80%80%NoNo80% 80%
Out-of-pocket limit***N/AN/AN/AN/AN/AN/A$5,880 in 2020$2,940 in 2020N/A N/A

* Part B coinsurance for Medigap plans applies when the Part B deductible is met.3

** Plan F and Plan G also offer high-deductible plans. If you choose either of these options, this means you must pay for Medicare-covered costs up to the deductible amount of $2,340 in 2020 before your Medigap plan pays anything.

*** After you meet your out-of-pocket yearly limit and your yearly Part B deductible, the Medigap plan pays 100% of covered Part B services for the rest of the calendar year.

**** Plan N pays 100% of the Part B coinsurance, except for a copay of up to $20 for some office visits and up to a $50 copay for emergency room visits that don’t result in an inpatient admission.

If you live in Massachusetts, Minnesota, or Wisconsin, Medigap policies are standardized in a different way.

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  1. Schnell, Scott, Susan M. Friedman, Daniel A. Mendelson, Karilee W. Bingham, and Stephen L. Kates. “The 1-Year Mortality of Patients Treated in a Hip Fracture Program for Elders.” Geriatric Orthopaedic Surgery & Rehabilitation, September 2010 (accessed September 2018).

  2. U.S. Government Website for Medicare. “2019 Choosing a Medigap Policy: A Guide to Health Insurance for People with Medicare.” (accessed March 2020).

  3. U.S. Government Website for Medicare. “How to compare Medigap policies.” (accessed February 14, 2020).