Medicare Supplement covers the costs Medicare leaves behind

Medicare Supplement insurance (also called Medigap) pays for the bills that Original Medicare does not. When you see a doctor or go to the hospital, Medicare Part A and Part B cover a portion of the cost. You are responsible for the rest — the deductible, the copayment, or the coinsurance. A Medigap policy picks up those out-of-pocket costs so you are not paying them yourself.

Medigap does not cover everything Medicare does not cover. It covers only the gaps in Original Medicare. If you have Medicare Advantage instead, Medigap does not work with it and you should not buy it.

Key Takeaways

  • Medigap pays the deductibles, copayments, and coinsurance that Original Medicare leaves you responsible for.
  • There are ten standardized Medigap plans (A through N), and each one covers a different combination of gaps.
  • Plan G and Plan N are the most common choices for people newly may be able to access, though the right plan depends on your doctor visits and hospital use.
  • You can buy Medigap from any insurance company, and the same plan letter covers the same things no matter which company sells it to you.
  • Medigap does not cover dental, vision, hearing aids, or long-term care — you need separate coverage or to pay out of pocket for those.

The ten Medigap plans and what each one covers

The federal government sets ten standardized Medigap plans, labeled A through N. Each plan covers a specific set of gaps in Medicare. Plan A is the most basic. Plan G covers more. Plan N covers different things than Plan G. Insurance companies must offer the same coverage for each letter — a Plan G from one company covers exactly what Plan G from another company covers.

The most common plans for people newly turning 65 are Plan G and Plan N. Plan G covers your Part B deductible, coinsurance, and copayments. It also covers coinsurance for skilled nursing facility care and the cost of blood transfusions. Plan N covers most of the same things, but it does not cover your Part B deductible, and it charges you a copayment when you see a doctor or go to urgent care. Plan N is usually cheaper per month, but you pay more when you use care.

Plans A, B, D, and F are also available, though Plan F is only for people who were may be able to access for Medicare before January 1, 2020. Plan F used to be the most popular because it covered nearly everything, but it is no longer sold to new Medicare beneficiaries. If you are newly may be able to access, you cannot buy it.

What Medigap does not cover

Medigap covers the gaps in Original Medicare, but it does not cover services that Medicare itself does not cover. Dental work, eye exams, eyeglasses, and hearing aids are not covered by Medicare, so Medigap does not cover them either. Long-term care in a nursing home or at home is not covered by Medicare or Medigap — you would need a separate long-term care insurance policy or to pay out of pocket.

Medigap also does not cover prescription drugs. If you take medications, you need a separate Part D prescription drug plan. You can have both Medigap and Part D at the same time.

Medigap does not cover care you receive outside the United States, except in limited situations when you are traveling. If you spend time abroad, ask your Medigap company what coverage applies.

How much Medigap costs and when you can buy it

Medigap premiums vary by plan, by insurance company, and by where you live. Plan A is usually the cheapest. Plan G usually costs more per month than Plan N, but you save money on copayments when you see doctors. There is no way to know which plan will cost you less overall without looking at your own doctor visits and hospital stays.

You have a six-month window to buy Medigap without being turned down for pre-existing conditions. This window starts the first day of the month you turn 65 and are enrolled in Medicare Part B. If you miss this window, insurance companies can charge you more or refuse to sell you a policy. Some states have longer windows or stronger protections, so check with your state insurance commissioner's office.

You can switch from one Medigap plan to another, but the rules depend on whether you are switching within the first six months or later. If you switch after the first six months, the new company can charge you more based on your health history.

How to compare Medigap plans for your situation

The right Medigap plan depends on how often you see doctors, whether you have ongoing health conditions, and how much you want to pay each month. If you see specialists regularly or have multiple chronic conditions, a plan that covers more (like Plan G) may save you money overall, even if the monthly premium is higher. If you are healthy and rarely see a doctor, a cheaper plan (like Plan A or Plan N) may be better.

You can get a side-by-side comparison of plans from Medicare.gov. Enter your state and zip code, and the site will show you which companies sell which plans in your area and what they charge. You can also call 1-800-MEDICARE to ask for a printed comparison.

When you compare, look at the total cost: the monthly premium plus what you would pay out of pocket for the care you actually use. A plan with a higher premium but lower copayments might cost less overall if you see doctors often.

Medigap versus Medicare Advantage: which covers what

Medicare Advantage (Part C) is a different way to get Medicare coverage. Instead of Original Medicare plus Medigap, you get all your coverage through one insurance company's plan. Medicare Advantage plans usually have lower monthly premiums than Original Medicare plus Medigap, but they have networks (you have to see doctors in the plan), and they often have higher copayments and deductibles.

If you have Medicare Advantage, you cannot buy Medigap. The two do not work together. If you are thinking about switching from Medicare Advantage to Original Medicare, you have a one-time chance to buy Medigap without being turned down for pre-existing conditions — but only if you switch within 12 months of first enrolling in Medicare Advantage.

What to ask your doctor and insurance company

Before you choose a Medigap plan, ask your doctor how many times a year you typically see them and whether you see specialists. Ask whether you have any upcoming procedures or treatments that might mean more doctor visits. This information helps you estimate which plan will cost you less overall.

When you call an insurance company to ask about a specific Medigap plan, ask what the monthly premium is, what the out-of-pocket costs are (copayments and coinsurance), and whether there are any waiting periods for pre-existing conditions. Ask whether the company will let you switch plans later if your needs change.

If you are unsure whether you should buy Medigap or Medicare Advantage, ask your state health insurance counselor. Most states have a free counseling program called SHIP (State Health Insurance information Program) that helps people understand their options. You can find your state's SHIP by calling 1-877-839-2675.

Frequently Asked Questions

Can I buy Medigap if I have a pre-existing condition?

Yes, if you buy within six months of turning 65 and enrolling in Medicare Part B. After that six-month window, insurance companies can turn you down or charge you more based on your health. Some states have longer windows. Check with your state insurance commissioner's office to see what applies where you live.

Does Medigap cover my prescriptions?

No. Medigap covers the gaps in Medicare's hospital and doctor coverage, but not prescriptions. You need a separate Part D prescription drug plan. You can have both Medigap and Part D at the same time, and most people do.

What is the difference between Plan G and Plan N?

Plan G covers your Part B deductible and most copayments. Plan N does not cover the Part B deductible, and it charges you a copayment for doctor visits and urgent care. Plan N usually costs less per month, but you pay more when you use care. Which one costs less overall depends on how often you see doctors.

Can I switch Medigap plans after I buy one?

Yes, but the rules change after your first six months. Within the first six months, you can switch to any plan without being charged more. After that, the new company can charge you more based on your health history. Some states have stronger protections for switching.

Does Medigap work with Medicare Advantage?

No. If you have Medicare Advantage, you cannot buy Medigap. The two do not work together. If you switch from Medicare Advantage to Original Medicare, you have 12 months to buy Medigap without being turned down for pre-existing conditions.