A Medicare card does not mean every approved health care bill is paid in full. Medicare Supplement Insurance can help people manage some costs left by Original Medicare. When we approach Medicare, we may want steadier bills and the freedom to choose providers. Those priorities can make the choice feel important.
We can compare what different policies cover, how premiums vary, and when enrollment protections apply. The right choice depends on the costs we want help managing and the coverage rules we need to keep. No single plan is best for everyone.
Key Takeaways
- Medigap can help pay some cost-sharing left by Original Medicare.
- Plan letters set standard benefits in most states.
- Premiums can differ between insurers, even for the same letter.
- Each person needs an individual policy.
- Enrollment timing can affect access and price.
How Does Medigap Work With Original Medicare?
With Original Medicare and Medigap, Medicare pays its share of an approved bill first, then the Medigap policy pays its share. Original Medicare is federal Medicare coverage made up of Part A hospital insurance and Part B medical insurance.
A person generally needs both Parts A and B to buy a Medigap policy. Medicare Supplement Insurance is private insurance that can help pay Original Medicare cost-sharing, such as deductibles and coinsurance.
A doctor or hospital that accepts Medicare sends the approved bill to Medicare first. Medicare reviews the claim and pays its share. Then the Medigap insurer handles its part of the bill under the policy’s benefits.
A Medigap policy covers one person, so each spouse needs a separate policy.
The policy does not replace the Part B premium. We pay that premium to Medicare, and we also pay the Medigap premium to the insurance company.
Medigap has no provider network when we use a doctor or hospital that accepts Medicare. We can see a specialist without a referral, and we can use eligible providers anywhere in the United States.
The CMS Medigap overview explains how Medicare pays before the policy handles its share. A provider that does not accept Medicare may not follow the same billing process.
Before enrolling, confirm that you have both Parts A and B and that the policy is sold in your state.
What Does Medicare Supplement Insurance Cover?
Medigap can cover specified Medicare cost-sharing, but it does not turn every health or support service into a covered benefit. The plan letter matters, because each type of supplement insurance has its own benefits.
Medigap coverage applies to eligible Medicare-approved services. A policy may pay some deductibles, coinsurance, or copayments that would otherwise come from our own pocket.
Cost-sharing for Medicare-approved care
Some benefits cover Part A coinsurance for as many as 365 extra hospital days after Medicare benefits run out. Basic benefits can also include Part B coinsurance or copayments.
Basic coverage may pay for the first three pints of blood used in a covered service. It can also help with Part A hospice care cost-sharing.
These benefits do not mean every plan pays every cost. We need to match the policy’s letter to the care and bills we expect.
Services Medigap generally excludes
Medigap generally does not pay for services outside Original Medicare’s covered benefits. Common examples include:
- Long-term care
- Routine dental care
- Routine vision care
- Hearing aids
- Private-duty nursing
These expenses can still matter when we plan for health care costs. A separate policy or service may be needed, depending on the expense.
Travel emergencies and prescription drugs
Some plans cover foreign-travel emergency care, but they do not cover routine care abroad. Plans C, D, F, G, M, and N pay 80% after a $250 deductible, up to a $50,000 lifetime limit.
That benefit is for qualifying emergencies, not checkups or planned treatment during travel. Foreign-travel coverage limits can help us compare the specific plan letters.
Medigap plans sold today do not include prescription drug coverage. We need a separate Medicare Part D plan for prescription drugs.
Check the benefit details for the exact plan letter before relying on it for travel care or a service outside Original Medicare.
How Do Medigap Plan Letters Compare?
A plan letter determines standardized benefits in most states, while the insurer sets the premium. The same letter generally means the same basic benefits across insurers in those states.
Plan G covers eligible Part B excess charges, but it does not cover the Part B deductible. In 2026, that deductible is $283, and the Part A inpatient hospital deductible is $1,736.
The chart compares key details for five common plan choices. A deductible is an amount we pay before a policy begins paying certain benefits.
| Plan | Part B excess charges | Part B deductible | Other cost-sharing feature |
|---|---|---|---|
| Plan G | Covered | Beneficiary pays $283 | Plan pays covered costs after deductible |
| Plan N | Not covered | Beneficiary pays $283 | May charge office and emergency-room copayments |
| High Deductible Plan G | Covered | $2,950 before benefits | Higher deductible before policy pays |
| Plan K | Not covered | Beneficiary pays $283 | 50% cost-sharing benefits; $8,000 annual limit |
| Plan L | Not covered | Beneficiary pays $283 | 75% cost-sharing benefits; $4,000 annual limit |
Plan N does not cover Part B excess charges. It may charge up to $20 for some office visits and up to $50 for emergency-room visits that do not lead to admission.
In 2026, Plans K and L pay 100% of covered services after the yearly Part B deductible and their annual out-of-pocket limits are met. Plan K’s limit is $8,000, while Plan L’s is $4,000.
Plan G benefit details show how coverage works after the Part B deductible. Plans C and F are not available to people who became eligible for Medicare on or after January 1, 2020.
Plans E, H, I, and J are no longer sold, though current policyholders can generally keep them. Massachusetts, Minnesota, and Wisconsin use different standardization rules.
For a 2027 comparison, check that year’s deductible and limit amounts rather than carrying 2026 figures forward. Compare the same plan letter across insurers only after checking that it is available to you.
How Much Does Medigap Cost?
In 2025, the average Medigap premium was $244 per month, while a Plan G policy averaged $194 per month. Those averages give us a national benchmark, not an individual quote.
Premiums for the same plan letter can vary by insurer and location. The price depends on the specific policy, so a national average cannot show what one person will pay.
Average premiums and recent changes
Average Medigap premiums rose 7% from 2024 to 2025 and 20% from 2020 to 2025. Plan G premiums rose 13% from 2024 to 2025 and 38% from 2020 to 2025.
Plan G accounted for 46% of policyholders in 2025, or 6.3 million people. Plan F accounted for 30%, or 4.2 million people.
2025 Medigap premium averages show why the $244 figure works as a broad cost reference. It does not promise the price available to a particular shopper.
What can change your premium?
Age and health rating rules can affect the premium an insurer offers. Insurers may use different pricing methods, and the method affects how a policy’s price changes over time.
Some policies use attained-age pricing, where premiums can rise as the policyholder ages. Other methods may base the starting price on age when coverage begins or apply the same base rate across ages.
Yearly rate changes can also raise the bill. A low starting premium may not stay at the same level in later years.
When comparing Medicare Supplement Insurance costs, we should review the price and how it may change. The monthly premium is only one part of our health care budget.
Compare current quotes for the same letter and confirm whether the listed premium can change under the insurer’s pricing method.
Which Plan Fits Your Budget and Care Needs?
For most newly eligible shoppers who want broad coverage, Plan G is the clearest starting point for comparison. It offers broad benefits for covered Original Medicare costs, after the beneficiary pays the Part B deductible.
Plan choice comes down to the balance between premium and cost-sharing. We can compare the way each option handles bills against our budget and care needs.
Best Medicare Supplement Plans for Different Needs
Plan G was the most popular Medigap plan type in 2025, with 46% of policyholders. Its popularity makes it a useful reference, but it does not make it right for everyone.
Plan N may suit someone who wants a lower premium and can manage more costs when receiving care. High Deductible Plan G may fit someone who can take on a larger deductible in exchange for a lower premium.
Plans K and L may appeal to people who value a defined annual out-of-pocket limit. Those plans also require beneficiaries to pay part of covered costs until the limit is reached.
Medicare SELECT policies can require members to use a network of hospitals and, in some cases, doctors. That network rule can affect how we get care.
Compare the details before choosing
Before choosing, we can check these four points:
- Expected care use, including regular visits and planned treatment
- Comfort with variable bills when care is needed
- Premium affordability now and over time
- Plan availability and any network restrictions
The best Medicare Supplement plans for 2027 depend on the costs and benefits available that year. We should use current-year plan costs and insurer quotes, not assume a 2026 amount carries forward.
Before applying, verify the plan’s availability and whether a Medicare SELECT network restriction applies.
Who Can Qualify for Medigap?
Most people qualify to buy Medigap when they are at least 65, enrolled in Parts A and B, and live where the policy is sold. That is the usual path for Medicare Supplement Insurance for seniors.
Enrollment in both Parts A and B is generally required. State rules can also affect whether a person under 65 may buy a policy.
Eligibility at age 65 and older
People age 65 or older can generally apply for a policy offered in their state when they have Parts A and B. The plan’s availability may differ by state.
To check the basic eligibility points, we can review:
- Medicare enrollment status, including Parts A and B
- State of residence and local policy availability
- Age or qualifying disability status
Coverage options before age 65
Some states let people buy Medigap before age 65 because of a disability or end-stage renal disease. Rules differ, and the available plans may be limited.
In 38 states, insurers must offer at least one kind of Medigap policy to beneficiaries under 65 with disabilities during an initial open enrollment period, regardless of health conditions.
In 2024, 8% of traditional Medicare beneficiaries under 65 with disabilities had Medigap. The share was 50% among beneficiaries age 65 and older.
These figures show that under-65 access is less common, even where protections apply. A disability-related enrollment right does not mean every plan is sold to every applicant.
Ask your state insurance department which under-65 options and enrollment protections apply where you live.
When Can You Buy or Change a Medigap Policy?
The strongest federal protection usually comes during the six-month period that begins when you are 65 or older and enrolled in Part B. This window limits how insurers can use health history.
During this six-month open enrollment period, insurers cannot deny coverage or charge more based on health. The period starts in the first month a person has Part B at age 65 or older.
The six-month open enrollment period
Outside that period, federal protections may apply after certain events. For most qualifying federal guaranteed-issue events, people age 65 or older generally have 63 days to apply.
Federal guaranteed-issue rights
Qualifying examples include an initial Part B enrollment period, a Medicare Advantage trial period, or a Medicare Advantage plan ending coverage in the beneficiary’s area.
Federal rights vary by event, so the same coverage and timing rules do not apply to every situation. Outside protected periods, federal law allows insurers to use medical underwriting.
| Situation | Application timing | Health underwriting protection |
|---|---|---|
| Six-month open enrollment | Six months starting with Part B at age 65 or older | No health-based denial or surcharge |
| Qualifying federal guaranteed-issue event | Generally 63 days for people age 65 or older | Protected rights apply |
| Outside protected periods | No general federal guaranteed-issue window | Insurers may use underwriting |
Medical underwriting can let an insurer deny an application or charge a higher premium based on health. A protected right can change that outcome.
State protections beyond federal rules
Eight states have relatively generous continuous or annual guaranteed-issue protections: Connecticut, Massachusetts, Maine, New York, Delaware, Illinois, Minnesota, and Rhode Island.
Connecticut, Massachusetts, Maine, and New York require continuous or annual protections for people age 65 and older, regardless of health history. The exact rules depend on the state.
Minnesota’s annual protections for people ages 65 to 70 took effect August 1, 2026. The state Medigap enrollment protections matter when comparing a change outside the federal window.
The CMS guidance on Medigap enrollment rights explains how guaranteed-issue protections can apply to certain coverage changes.
Before switching outside a protected period, confirm in writing whether underwriting could affect approval or premium.
How Is Medigap Different From Medicare Advantage?
Medigap supplements Original Medicare, while Medicare Advantage replaces Original Medicare as the way a beneficiary receives Parts A and B coverage. They are different paths, not two policies that work together.
Medigap can help pay cost-sharing left by Original Medicare, but it does not work with Medicare Advantage. Medicare Advantage is another way to receive Medicare coverage, through Part C.
With Original Medicare, Medicare processes covered claims and a Medigap policy may pay some remaining costs. With Medicare Advantage, the plan itself delivers Medicare coverage under its own terms.
Beneficiaries cannot use Medigap to pay Medicare Advantage cost-sharing. Insurers generally cannot sell a Medigap policy to someone enrolled in Medicare Advantage.
A person switching from Medicare Advantage back to Original Medicare should check for a guaranteed-issue right before making the change. A protected right may help the person buy a Medigap policy without health-based denial.
Do not end a current policy until replacement coverage has a confirmed effective date.
Coverage dates can affect whether we have a gap in health insurance or pay for overlapping coverage. We should line up the new start date with the end date of existing coverage.
Confirm the effective date of any replacement coverage before ending an existing policy.
Conclusion
A sound Medigap choice balances the costs we can manage with the coverage we want. In most states, a plan letter sets standard benefits, while the insurance company sets the premium.
Enrollment protections can matter as much as the plan itself. We can check the plans and current quotes available in our state, then confirm any enrollment rights before applying.
Compare the same letter across insurers and confirm your enrollment protections before you submit an application.