What Are Medicare Supplements? A Guide to Medigap Plans

If you’re approaching retirement or already enrolled in Medicare, you’ve probably heard the term “Medicare Supplement” or “Medigap.” These plans play a critical role in helping millions of Americans reduce their healthcare expenses. But what exactly are Medicare Supplement plans, how do they work, and are they right for you?

In this article, we’ll explore Medicare Supplement Insurance—also known as Medigap—including how it works, what it covers, and how to choose the right plan for your needs and budget.

What Is a Medicare Supplement Plan?

A Medicare Supplement Insurance plan, commonly called Medigap, is a private insurance policy that helps cover the “gaps” in Original Medicare (Parts A and B). While Medicare covers a significant portion of your medical expenses, it doesn’t pay for everything. That’s where Medigap comes in.

Medigap plans help cover:

• Deductibles

• Copayments

• Coinsurance

• Emergency care when traveling abroad (in many plans)

Without a supplement plan, those out-of-pocket costs can quickly add up—especially if you have frequent doctor visits or hospital stays.

How Does Medigap Work?

Here’s a simple breakdown:

1. You visit a healthcare provider.

2. Medicare pays its share of the approved charges.

3. Your Medigap plan then pays its share of the remaining costs—depending on the plan you choose.

This coordination between Medicare and your supplement insurance can reduce or eliminate unexpected bills, giving you greater peace of mind and more predictable healthcare expenses.

Who Is Eligible for a Medicare Supplement Plan?

To buy a Medigap policy, you must:

• Be enrolled in both Medicare Part A and Part B

• Not be enrolled in a Medicare Advantage (Part C) plan

The best time to enroll in a Medigap plan is during your Medigap Open Enrollment Period—a six-month window that starts the first month you’re 65 or older and enrolled in Part B. During this time:

• You can buy any Medigap policy available in your state.

• You can’t be denied coverage due to pre-existing conditions.

• You’ll get the best pricing available based on your age and location.

If you wait until after this period, insurers may require medical underwriting and can deny coverage or charge more based on your health.

What Does Medigap Cover?

Medigap policies are standardized and labeled by letters: Plans A, B, C, D, F, G, K, L, M, and N. Each lettered plan offers a different combination of benefits, but the coverage within each plan is the same regardless of which insurance company offers it.

Here’s a look at what many Medigap plans may help cover:

• Part A coinsurance and hospital costs

• Part B coinsurance or copayment

• First three pints of blood

• Part A hospice care coinsurance or copayment

• Skilled nursing facility care coinsurance

• Part A and B deductibles (some plans)

• Foreign travel emergency coverage (up to plan limits)

Note: Plans C and F are no longer available to new Medicare enrollees as of January 1, 2020, but those already enrolled can keep them.

Most Popular Medigap Plans

Plan G

• The most comprehensive plan available to new enrollees

• Covers nearly all out-of-pocket costs except the Part B deductible

• High-deductible version available for lower premiums

Plan N

• Offers strong coverage with lower premiums

• Requires copays for doctor visits and emergency room visits

• Does not cover the Part B deductible or excess charges

Plan F (grandfathered)

• Pays all gaps in Medicare coverage, including Part B deductible

• Only available if you were eligible for Medicare before 2020

What’s Not Covered by Medigap?

Medigap policies do not include:

• Prescription drug coverage (you’ll need a separate Part D plan)

• Dental, vision, or hearing services

• Long-term care (custodial care)

• Private-duty nursing

If you want those benefits, you’ll need additional coverage through stand-alone policies or a Medicare Advantage plan.

How Much Do Medicare Supplements Cost?

The cost of a Medigap policy varies based on:

• Your age

• The plan letter you choose

• Your location

• The insurance company

• Whether the plan uses community-rated, issue-age-rated, or attained-age-rated pricing

Typical premium range:
Most people can expect to pay between $100 to $300 per month, depending on their plan and location. High-deductible plans can be much more affordable upfront.

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

While both options help cover costs beyond Original Medicare, they’re structured very differently:

Your decision should depend on your personal preferences, travel habits, healthcare usage, and budget.

Final Thoughts

Medicare Supplement Insurance plays a vital role in helping retirees and those on Medicare manage their healthcare costs with confidence. By covering deductibles, coinsurance, and copayments, Medigap plans reduce financial stress and allow for more predictable medical expenses.

If you value flexibility in choosing doctors and hospitals, want to avoid surprise bills, or travel frequently, a Medigap plan may be the best fit. Make sure to enroll during your Medigap Open Enrollment Period to lock in the best rates and avoid medical underwriting.

Navigating Medicare doesn’t have to be overwhelming—especially when you understand the tools available to protect your health and your wallet.