Medicare Supplement

The Ultimate Guide to Understanding Your Coverage Options

Medicare Supplement, also known as Medigap, is a type of insurance that helps cover the gaps in Medicare coverage. It is designed to work alongside Original Medicare and provides additional benefits that are not covered by Medicare, such as copayments, deductibles, and coinsurance. This article will provide an in-depth look at Medicare Supplement and what it means for your health coverage.

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What is Medigap?

Medigap, also known as Medicare Supplement Insurance, is a private insurance that helps cover the out-of-pocket costs not covered by Original Medicare.

These costs can include 

  • copayments,
  • coinsurance,
  • and deductibles.

Medigap policies are sold by private insurance companies and can help pay for some of the remaining health care costs not covered by Original Medicare.

Medigap policies can also cover services that Original Medicare does not, such as medical care when traveling outside the US. If you have Original Medicare and purchase a Medigap policy, Medicare will pay its share of the Medicare-approved amount for covered health care costs.

The Medigap insurance company will then pay its share of any remaining costs.

Medigap in Oregon

  • As of 2022, there are 29 insurance companies that offer Medigap plans in the state of Oregon.
  • The approach to determining premiums for Medigap plans can vary among insurers.
  • Oregon does not mandate a specific approach, so most insurance companies in the state use attained-age rating, resulting in premiums increasing as the enrollee gets older.
  • Some Medigap insurers use issue-age rating, where premiums are based on the age the person was when they enrolled.
  • An analysis by AHIP shows that as of 2020, 188,400 Medicare beneficiaries in Oregon had Medigap coverage.
Medicare Supplement Plans

What you should know about Medicare Supplement:

  • You must have Medicare Part A and Part B.
  • Medigap is a type of insurance policy that supplements Original Medicare, while a Medicare Advantage Plan is a way to receive Medicare benefits
  • In addition to paying the monthly Part B premium to Medicare, you also pay a separate monthly premium to the private insurance company for your Medigap policy.
  • Medicare Supplemental plans are STANDARDIZED and serve people with chronic health conditions well.
  • The top 3 Medicare Supplemental Plans are Plan F, G, and N.
  • People who enroll with Medicare Supplement Plan pays most of their healthcare cost in advance, but generally lesser than Original Medicare or Medicare Advantage Plan
  • If you and your spouse both want Medigap coverage, separate policies will need to be purchased for each person, as a Medigap policy only covers one individual.
  • If you have an older Medigap policy that included drug coverage before January 1, 2006, you can keep it. However, new Medigap policies cannot include drug coverage. You may choose to enroll in a separate Medicare Prescription Drug Plan (Part D) because most Medigap drug coverage is not considered creditable, meaning you may pay more if you join a drug plan later. If you purchase both Medigap and a Medicare drug plan from the same company, you may need to make separate premium payments. It’s best to contact the company for information on how to pay your premiums.

How Does Medicare Supplement Work?

Medicare Supplement policies are designed to work alongside Original Medicare, meaning that you must first enroll in Medicare Part A and Part B in order to be eligible for a Medicare Supplement policy.

When you receive health care services, Original Medicare pays its share of the costs, and Medicare Supplement covers any remaining costs, such as copayments, deductibles, and coinsurance.

Who is Eligible for Medicare Supplement?

To be eligible for Medicare Supplement, you must be enrolled in Medicare Part A and Part B and reside in the state where the policy is sold. You may also need to pass medical underwriting, which means that the insurance company will evaluate your health status to determine your eligibility.

What does Medigap cover?

A Medigap policy may pay for some or all of the remaining costs that Original Medicare does not cover. This can include outstanding deductibles, coinsurance, and copayments. Additionally, Medigap may provide coverage for medical expenses not covered by Medicare, such as care received while traveling abroad.

What Medigap doesn’t cover

Medigap policies, also known as supplementary Medicare insurance, do not cover all healthcare expenses. They typically do not cover long-term care, private-duty nursing, and other insurance plans.

These insurance plans are NOT Medigap

There are several types of insurance that are not considered Medigap plans, including:

  • Medicare Advantage Plans,
  • Medicare Prescription Drug Plans,
  • Medicaid,
  • employer or union plans,
  • Tricare,
  • veterans’ benefits,
  • long-term care insurance policies,
  • Indian Health Service, Tribal, and Urban Indian Health plans.

How much does Medigap Cost?

When selecting a Medigap policy, it is important to consider options from multiple insurance companies, particularly if you have already chosen a specific standardized policy. Keep in mind that policies with the same letter name provide the same coverage, but premiums may vary among companies. For example, Policy A from one company may have a different premium than Policy A from another company.

When evaluating Medigap policies, it’s important to ask the insurance company what factors they use to determine your premium. These factors may include

  • where you live,
  • your age,
  • health status,
  • gender,
  • smoking status,
  • and marital status.

It is generally recommended to purchase a Medigap policy during your open enrollment period or when you have a guaranteed issue right to avoid premium variations based on your health status.

It’s important to be aware of how Medigap insurance companies determine the cost of premiums based on age. In some states, the way in which age is used to set premiums is regulated. Depending on your state, premiums may be:

  • No-age-rated (also known as community-rated), where premiums are the same for everyone living in a specific area, regardless of age and are generally the least expensive over your lifetime.
  • Issue-age-rated, where premiums are based on the age when you first bought the policy. The younger you are when you purchase a Medigap, the cheaper your premium will be, although premiums will still increase over time due to inflation but not due to age
  • Attained-age-rated, where premiums are initially based on your age when you purchase a policy, and they increase as you get older, meaning you pay a different price at age 65 than you do at age 70. These premiums may be the lowest when you first buy them but are generally the most expensive over your lifetime.

What are the Different Types of Medicare Supplement Policies?

There are 10 standardized options available, labeled A, B, C, D, F, G, K, L, M and N. Each policy has the same benefits regardless of the insurance provider or cost. However, not all companies may offer all 10 options, and availability may vary by state.

Medigaps are supplementary insurance policies that assist with certain expenses not covered by Medicare, such as deductibles, coinsurance, and copays. They do not cover Medicare premiums.

All Medigap policies must provide basic benefits, including

  • hospital coinsurance coverage,
  • additional hospital coverage days,
  • coverage for certain Part B services,
  • coverage for a certain number of pints of blood,
  • and hospice coinsurance for drugs and respite care.

Medigap policies can vary in terms of the extent of coverage they provide, with Policy A typically being the most affordable but covering only the basic benefits, while Policies C and F tend to be more comprehensive but also more expensive. For more detailed information, refer to the Medigap Plan Benefits Chart.

Comparing Medigap Plans Medicare Supplement Plans


When can I enroll for Medigap?

When purchasing a Medigap policy, it is important to be aware of the specific regulations and guidelines for buying one in your state. In most states, insurance companies have certain windows of opportunity for selling Medigap policies and specific requirements that must be met. If you miss this window, you may face increased costs, limited options, or be unable to buy a Medigap policy at all. 

Open Enrollment Period

It’s generally advisable to enroll in a Medigap policy during your open enrollment period. This is a six-month window that starts when you turn 65 and enroll in Medicare Part B. During this period, Medigap insurers are legally required to sell you a policy at the best available rate regardless of your health status and cannot deny you coverage. Factors that may affect the rate include your age, gender, smoking habits, marital status, and location. To ensure you’re getting the best rate, you can check with your SHIP. Additionally, policies purchased during open enrollment period are limited in their ability to exclude coverage for pre-existing conditions.

Guaranteed Issue Right

If you miss your open enrollment period for purchasing a Medigap policy, you may still be able to buy one under a guaranteed issue right. This right allows you to purchase a Medigap policy within 63 days of losing or ending certain types of health coverage.

During this time, Medigap companies must sell you a policy at the best available rate, regardless of your health status and cannot deny you coverage. Additionally, the guaranteed issue right also prevents companies from imposing a waiting period for coverage of pre-existing conditions.

You may have a guaranteed issue right if you

  • lose a group health plan,
  • disenroll from a Medicare Advantage plan within 12 months,
  • or if your previous Medigap policy, Medicare Advantage plan, or PACE program ends its coverage or commits fraud.

Keep proof of your lost or ended coverage in case it is required by the Medigap insurer.

>>> Learn More about Medicare Enrollment Periods

Can I buy Medigap outside enrollment periods?

Purchasing a Medigap policy outside of protected enrollment periods can be difficult as companies may refuse to sell you one or impose certain medical requirements. If a company does agree to sell you a policy, it may come with a higher monthly premium and a six-month waiting period for coverage of pre-existing conditions. It is important to check with Medigap insurers in your state to understand their policies.

Medigap Enrollment in Oregon

Medigap plans are standardized across the country at the federal level. Federal law guarantees access to Medigap plans for individuals who are at least 65 years old and enrolled in Medicare Part B, and are also enrolled in Medicare Part A. The six-month open enrollment period for Medigap plans starts when the individual meets these criteria.

Unlike Medicare Advantage and Part D, there is no federal annual open enrollment period for Medigap plans; once the initial six-month window ends, it is no longer available. Individuals who wish to switch to a different Medigap plan are generally subject to medical underwriting and may not be able to do so if they have pre-existing medical conditions. Additionally, individuals under 65 years of age who are eligible for Medicare due to a disability or having end-stage renal disease or ALS are not guaranteed access to Medigap under federal rules.

Oregon Birthday Rule on Medicare Supplement

In Oregon, there is a birthday rule for Medicare Supplement or Medigap Policies. The state allows 31 days to change your Medigap policy, skipping the underwriting process. This rule starts on your birthday each year and gives you a chance for open enrollment for the next 30 days. During this time, you’re able to switch your Medicare supplement to another carrier with either the same exact Medicare Supplement or lower plan option. 

For example, you can switch from Plan F to Plan F or Plan F to Plan G to save money on your premium. This requires an ACTIVE Medicare Supplement plan. For an individual with Medicare Advantage plans, still need to undergo the underwriting process when applying for Medigap (given that they don’t qualify for guaranteed- issues).

Additional Tip:

Therefore, beneficiaries shop around to find a Supplement plan that is right for both their medical and financial needs. Since Jan. 1, 2013, Medicare beneficiaries also have a yearly opportunity to compare supplement prices and switch companies. They must keep the same plan type or choose one with lesser benefits. Out-of-pocket costs with Medicare Supplement plans may also include monthly premiums and yearly deductibles.

 Medicare Supplement for People with Disability under 65

If you are under 65 and qualified for Medicare due to disability or End Renal Stage (ESRD), your eligibility for Medicare Supplement Plans depends on your location. Rules governing the availability of Medicare Supplements vary from every state. Though the federal law states Medicare supplement guaranteed-issue proper protection for beneficiaries, it is not required that Medicare Insurance carriers must sell Medigap plans to people under 65. Mainly, due to higher posted risk and lesser competition, the cost of the plans may be higher, and there are chances for coverage to be denied due to pre-existing conditions. It is better to visit first the insurance board’s website to review your rights as a beneficiary.

Oregon is among the 29 states that require insurers to sell Medicare Supplement plans to anyone, regardless of age, as long as they are eligible for Medicare.

Choosing the Right Medigap Plan

When speaking with insurance representatives about Medigap policies, it is important to ask the following questions:

  • Are you enrolling during your open enrollment period or do you have a guaranteed issue right?
  • What is the monthly premium for the Medigap policy?
  • Is the premium based on factors such as your health status, gender, smoking, marital status, or anything else?
  • Are the premiums no-age-rated, issue-age-rated, or attained-age-rated?
  • Will the company refuse to sell you a Medigap based on your health status?
  • Does the policy have a waiting period for pre-existing conditions?
  • How long is the waiting period before coverage begins?
  • Do you have prior creditable coverage to reduce the waiting period?

Additionally, if you do not have the right to buy a Medigap, ask the insurance representative about any additional charges for purchasing one. If you are under 65, ensure that the company you are considering sells Medigap policies to individuals under 65. 

Medicare Supplement Plan vs Medicare Part C

Medicare Part C, also known as Medicare Advantage, is a type of Medicare health plan offered by private insurance companies that are approved by Medicare. These plans provide the same coverage as Original Medicare (Part A and Part B) but may also offer additional benefits.

Medigap, also known as Medicare Supplement Insurance, is a type of private insurance that is designed to supplement Original Medicare by covering some of the out-of-pocket costs that Original Medicare does not cover, such as deductibles, coinsurance, and copays.

While Medigap and Medicare Part C both help with cost-sharing, they are different types of coverage. Medigap policies only work with Original Medicare while Medicare Advantage plans provide an alternative to Original Medicare.

The choice between Medigap and Medicare Advantage plans depends on the person’s needs, preferences and budget.

How do I choose between Medigap and Medicare Advantage?

When deciding on your main coverage for healthcare, you must choose between original Medicare, and may be supplemented with a private Medigap policy, or a Medicare Advantage plan which is provided by a private insurer.
Original Medicare allows you to see any doctor and facility that accepts Medicare, but you will have to pay for additional Medigap and Part D drug coverage. Medicare Advantage plans may have lower or no additional premiums beyond your monthly Part B premium, but out-of-pocket expenses may vary.
These plans typically require you to use a provider network, so if you see an out-of-network doctor, the plan may not cover the visit or you will pay a higher copayment. Additionally, most Medicare Advantage plans include prescription drug coverage and may cover extra expenses.

Frequently Asked Questions

Q: Is Medicare Supplement the same as Medicare Advantage?

A: No, Medicare Supplement is different from Medicare Advantage. Medicare Advantage is a type of health plan that replaces Original Medicare and provides all of your Part A and Part B benefits, as well as additional benefits like prescription drug coverage. Medicare Supplement, on the other hand, works alongside Original Medicare and provides additional benefits that are not covered by Medicare.

Q: Can I cancel my Medigap Plan?

A: Individuals have the right to review a new Medigap policy for the first 30 days, and can cancel it within that time for a full refund if it does not meet their needs. However, cancelling a Medigap policy later on may limit the ability to purchase another policy or result in higher premiums due to health status.

Q: Can I have both Medicare Supplement and Medicare Advantage?

A: No, you cannot have both Medicare Supplement and Medicare Advantage at the same time. You must choose one or the other.

Q: Is it possible to switch my Medicare Supplement Policy?

A: Yes. People with Medicare Supplemental Plans may switch anytime but may face some restrictions if one doesn’t have guaranteed-issue-right outside One time Enrolment period (OEP). To change policy, one must apply for a new plan. Once accepted, your present insurance company must be notified to cancel the current coverage.

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