Medigap Medicare Supplement Insurance: What It Is, How It Works & How to Choose a Plan

If you have Original Medicare, you may discover that Medicare doesn’t pay every healthcare expense.

That’s where Medigap Medicare Supplement Insurance comes in.

Medigap, also called Medicare Supplement Insurance, is private insurance designed to work alongside Original Medicare. It can help pay certain out-of-pocket healthcare costs that remain after Medicare pays its share, including deductibles, coinsurance and copayments, depending on the plan you select.

If you’re approaching age 65, retiring, losing employer health coverage or simply trying to understand your Medicare choices, learning how Medigap works is an important place to start.

For a complete overview of available coverage, see our Medicare Supplement Plans guide.

What Is Medigap?

Medigap is Medicare Supplement Insurance.

It is private health insurance designed to supplement Original Medicare — Medicare Part A and Medicare Part B.

The basic idea is simple:

Original Medicare pays first. Your Medigap policy may then help pay certain remaining Medicare-approved costs according to the benefits of your policy.

That’s where the name Medigap comes from: the insurance helps cover some of the financial “gaps” left by Original Medicare.

Learn more in our complete guide to Medicare Supplement Insurance.

Is Medicare Supplement Insurance the Same as Medigap?

Yes. Got questions speak to an agent by calling toll-free 1-800-MEDIGAP

Medicare Supplement Insurance and Medigap are two names commonly used for the same type of supplemental insurance.

You may encounter terms such as:

• Medigap
• Medigap insurance
• Medigap plans
• Medicare Supplement Insurance
• Medicare Supplement plans
• Medicare supplemental insurance

These terms generally describe private supplemental policies designed to work alongside Original Medicare.

How Does Medigap Medicare Supplement Insurance Work?

Original Medicare consists primarily of:

Medicare Part A — Hospital Insurance

Part A helps cover inpatient hospital care and certain other eligible healthcare services.

Medicare Part B — Medical Insurance

Part B helps cover eligible physician services, outpatient care, preventive services and other medically necessary services.

When you receive a Medicare-covered service, Original Medicare generally pays its portion of the Medicare-approved amount first.

Your Medigap policy can then help pay certain remaining costs according to the standardized benefits of your particular plan.

This combination can make healthcare expenses more predictable because Medigap can reduce your exposure to some of the deductibles, copayments and coinsurance associated with Original Medicare.

What Does Medigap Cover?

The exact benefits depend on the standardized Medigap plan you select.

Depending on the plan, Medicare Supplement Insurance may help pay expenses including:

• Medicare Part A coinsurance
• Additional hospital costs after Medicare benefits are used
• Medicare Part B coinsurance or copayments
• The first three pints of blood
• Part A hospice care coinsurance or copayments
• Skilled nursing facility care coinsurance
• Medicare Part A deductible
• Medicare Part B excess charges
• Certain foreign travel emergency expenses

Not every Medigap plan covers every benefit.

That’s why consumers should compare the Medigap plan letters and benefits before choosing coverage.

You can see the standardized benefits side-by-side using our Medigap Plan Comparison Chart.

What Doesn’t Medigap Cover?

Medigap is designed primarily to help with certain costs associated with Original Medicare. It isn’t comprehensive coverage for every healthcare expense.

Medigap policies generally don’t cover services such as:

• Routine dental care
• Routine vision care
• Eyeglasses
• Hearing aids
• Long-term custodial care
• Private-duty nursing
• Prescription drugs

Modern Medigap policies don’t include Medicare prescription drug coverage.

If you have Original Medicare and need prescription drug coverage, you can consider a separate Medicare Part D prescription drug plan.

Read more about whether Medigap covers prescription drugs.

What Are the Different Medigap Plans?

In most states, Medigap policies are standardized and identified by letters.

Standardized Medigap plans include:

Plans A, B, C, D, F, G, K, L, M and N.

Not every insurance company offers every plan, and not every plan is available to every Medicare beneficiary.

Massachusetts, Minnesota and Wisconsin standardize Medicare Supplement policies differently.

One of the most important things to understand about Medigap is that the basic benefits of policies with the same letter are standardized.

For example, one insurance company’s standardized Plan G provides the same basic standardized benefits as another insurance company’s Plan G.

However, the companies can charge different premiums.

That’s why comparing both plans and insurance companies can be important.

What Is Medicare Supplement Plan G?

Medicare Supplement Plan G is one of the most comprehensive Medigap options available to people who are newly eligible for Medicare.

Plan G helps cover many of the out-of-pocket costs associated with Original Medicare.

It includes coverage for benefits such as:

• Medicare Part A hospital coinsurance
• Medicare Part A deductible
• Medicare Part B coinsurance
• Skilled nursing facility coinsurance
• Medicare Part B excess charges
• Certain foreign travel emergency expenses

Plan G does not cover the annual Medicare Part B deductible.

Once you’ve satisfied the Part B deductible, Plan G can substantially reduce your remaining eligible Original Medicare cost-sharing.

What Is Medicare Supplement Plan N?

Medicare Supplement Plan N is another popular Medigap option.

Plan N covers many of the same Original Medicare gaps as Plan G but uses additional cost-sharing for certain services.

For example, Plan N may require copayments for some office and emergency-room visits and doesn’t cover Medicare Part B excess charges.

In exchange for accepting some additional out-of-pocket costs, Plan N may have a lower monthly premium than Plan G.

If you’re deciding between these two options, see our detailed Plan G vs. Plan N comparison.

How Much Does Medigap Cost?

There isn’t one universal price for Medigap Medicare Supplement Insurance.

Premiums can vary based on factors including:

• Medigap plan letter
• Insurance company
• State and ZIP code
• Age
• Tobacco use
• Available household discounts
• The insurance company’s pricing method
• When you enroll
• Whether medical underwriting applies

This creates an important shopping opportunity.

Because standardized Medigap policies with the same letter provide the same basic benefits, two insurance companies can potentially charge different premiums for substantially the same standardized coverage.

That means consumers shouldn’t automatically select the first company or quote they find.

You can request Medicare Supplement quotes to compare available options.

When Is the Best Time to Buy Medigap?

For many people, the most important period is their Medigap Open Enrollment Period.

This six-month period generally begins the first month you are both:

65 or older AND enrolled in Medicare Part B.

During this period, federal protections generally allow you to purchase any Medigap policy sold in your state regardless of health problems.

Your Medigap Open Enrollment Period is not the same thing as Medicare’s annual Open Enrollment Period.

That’s an important distinction.

Learn more about the timing and rules in our Medigap Open Enrollment guide.

Can I Buy Medigap After Open Enrollment?

Possibly.

However, your options can change after your Medigap Open Enrollment Period ends.

Depending on your circumstances and state law, an insurance company may be permitted to use medical underwriting to determine whether to issue a policy and what you may pay.

Certain situations can also give you guaranteed-issue rights.

Because the rules can depend on your individual situation, it’s wise to investigate your eligibility before canceling existing insurance or making a coverage change.

Medigap vs. Medicare Advantage: What’s the Difference?

This is one of the most important distinctions for people approaching Medicare.

Medigap and Medicare Advantage are not the same thing.

Medigap supplements Original Medicare.

Medicare Advantage — Medicare Part C — is an alternative way to receive your Medicare Part A and Part B benefits through a private Medicare-approved plan.

With Original Medicare + Medigap, Original Medicare remains your primary Medicare coverage and your Medigap policy supplements eligible costs.

With Medicare Advantage, you receive Medicare-covered services through the Medicare Advantage plan according to its benefits, provider network and rules.

You generally cannot use Medigap to pay Medicare Advantage deductibles, copayments or premiums.

If you’re deciding between these two approaches, read our complete Medigap vs. Medicare Advantage comparison.

Can I Use Medigap Anywhere in the United States?

One of the important features of Original Medicare combined with Medigap is provider flexibility.

With Original Medicare, you generally can receive Medicare-covered care from doctors and hospitals throughout the United States that participate in Medicare.

Because Medigap supplements Original Medicare rather than replacing it with a separate healthcare network, this can be particularly attractive to:

• Frequent travelers
• Snowbirds
• Retirees with homes in multiple states
• People who want access to specialists outside their local area
• People who prefer not to rely on a local Medicare Advantage provider network

Always verify that a healthcare provider accepts Medicare before receiving care.

Does Medigap Cover International Travel?

Some standardized Medigap plans include limited foreign travel emergency benefits.

This isn’t the same as comprehensive international health insurance or travel insurance.

If international travel is important to you, compare the specific foreign-travel benefits, deductibles and limits associated with the Medigap plans you’re considering.

Does Medigap Include Prescription Drug Coverage?

Modern Medigap policies don’t include Medicare prescription drug coverage.

Someone using Original Medicare may therefore have coverage structured like this:

Medicare Part A + Medicare Part B + Medigap + Medicare Part D

Each component serves a different purpose.

Part A primarily covers hospital care.

Part B primarily covers physician and outpatient medical services.

Medigap helps cover certain Original Medicare cost-sharing.

Part D provides prescription drug coverage.

Can My Spouse Be Covered Under My Medigap Policy?

No.

A Medigap policy covers one individual.

If both spouses want Medicare Supplement Insurance, each generally needs an individual Medigap policy.

That’s different from many employer health plans where spouses may share one family policy.

How Should I Compare Medigap Insurance Companies?

Because Medigap plans are standardized, comparing companies involves more than simply looking at the benefits.

Consider:

Monthly premium: How much does each insurer charge for the same standardized plan?

Pricing methodology: How does the insurer determine premiums?

Potential rate changes: How could your premium change over time?

Financial strength: What do independent rating organizations report about the insurance company?

Customer service: How does the company handle questions and policy servicing?

Household discounts: Are discounts available?

Availability: Does the company offer the Medigap plan you want where you live?

Most importantly, compare the same plan letter across multiple insurance companies.

If you’re considering Plan G, for example, compare Plan G against Plan G rather than assuming a higher-priced company’s standardized benefits are necessarily better.

How Do I Choose a Medicare Supplement Plan?

Start with your personal healthcare and financial priorities.

Ask yourself:

How important are predictable healthcare expenses?

How much monthly premium am I comfortable paying?

How frequently do I visit physicians or specialists?

Do I travel frequently?

Do I spend significant time in multiple states?

Do I want the broader standardized benefits of Plan G or potentially lower premiums with Plan N?

What are different insurance companies charging for the same plan?

Am I currently within my Medigap Open Enrollment Period?

There isn’t one Medigap plan that’s automatically right for everyone.

The objective is to find the combination of benefits, premium and insurance company that fits your individual circumstances.

Frequently Asked Questions About Medigap Medicare Supplement Insurance

What does Medigap mean?

Medigap is Medicare Supplement Insurance. It is private insurance designed to help cover certain out-of-pocket expenses that Original Medicare leaves behind.

Is Medigap the same as Medicare Supplement Insurance?

Yes. Medigap and Medicare Supplement Insurance are two names for the same general type of supplemental insurance designed to work with Original Medicare.

Do I need Medicare Part A and Part B to get Medigap?

Generally, yes. Medigap is designed to supplement Original Medicare, which consists of Medicare Part A and Medicare Part B.

Is Medigap part of Medicare?

No. Private insurance companies sell Medigap policies. The coverage works alongside Original Medicare but isn’t itself Original Medicare.

Is Medigap the same as Medicare Advantage?

No. Medicare Advantage is an alternative way of receiving Medicare benefits through a private Medicare-approved plan. Medigap supplements Original Medicare.

Read our Medigap vs. Medicare Advantage guide for a detailed comparison.

Does Medigap cover prescription drugs?

Modern Medigap policies don’t include prescription drug coverage. People using Original Medicare can consider a separate Medicare Part D prescription drug plan.

Learn more about Medigap and prescription drug coverage.

What is the difference between Plan G and Plan N?

Both plans cover many of the major cost-sharing gaps associated with Original Medicare.

Plan G generally provides more comprehensive standardized coverage, while Plan N uses certain copayments and doesn’t cover Part B excess charges.

See our complete Plan G vs. Plan N comparison.

How do I compare Medigap plans?

Start by comparing the standardized benefits offered by each plan letter. Then compare premiums for the same plan across multiple insurance companies.

Use our Medigap Plan Comparison Chart to see your options side-by-side.

Compare Medigap Medicare Supplement Insurance Options

Choosing Medicare coverage can be one of the most important healthcare decisions you make as you approach retirement.

Understanding Medigap Medicare Supplement Insurance is a good first step.

Before enrolling, compare:

• Medigap plan benefits
• Plan G vs. Plan N
• Monthly premiums
• Insurance companies
• Enrollment timing
• Provider flexibility
• Prescription drug needs
• Your expected healthcare usage

If you’re turning 65, retiring, losing employer coverage or already enrolled in Medicare, you can speak with a licensed insurance professional to understand the Medicare Supplement options available to you.

Want to compare Medigap plans and prices?

Compare Medicare Supplement quotes or call 1-800-MEDIGAP (1-800-633-4427) to speak with a licensed insurance specialist.

1-800-MEDIGAP is a private insurance resource and is not affiliated with or endorsed by the U.S. government or the federal Medicare program. We do not offer every plan available in your area. Information provided is limited to the plans we offer. Contact Medicare.gov or 1-800-MEDICARE for information about all of your Medicare options.