Navigating Medicare can be confusing, especially when you start hearing about Medigap, Medicare Advantage, and Parts A through D. If you’ve ever wondered what Medigap actually is — and whether it might be right for you — this quick guide will help you understand the basics.
What Is Medigap?
Medigap, also known as Medicare Supplement Insurance, is private insurance designed to fill the “gaps” in Original Medicare (Parts A and B).
While Medicare covers a large portion of your healthcare expenses, it doesn’t cover everything — you’re still responsible for deductibles, coinsurance, and copayments. That’s where a Medigap plan can help. It picks up some (or all) of those out-of-pocket costs, depending on which plan you choose.
How Does Medigap Work?
Medigap works alongside Original Medicare — not as a replacement for it. Here’s how it works:
Medicare pays its share of approved healthcare costs first.
Then your Medigap policy pays its share of the remaining balance.
You can see any doctor or specialist who accepts Medicare — no network restrictions.
Each Medigap plan is standardized by the federal government and labeled with a letter (Plan A, B, D, G, K, L, M, or N). This means that coverage for each plan type is the same no matter which insurance company offers it — only the premiums differ.
Medigap vs. Medicare Advantage
It’s easy to confuse Medigap with Medicare Advantage (Part C), but they are very different:
Medigap supplements Original Medicare.
Medicare Advantage replaces Original Medicare and bundles hospital, medical, and sometimes drug coverage in one plan.
You can have either Medigap or Medicare Advantage, but not both.
What Does Medigap Cover?
Depending on the plan you choose, Medigap can help pay for:
Medicare Part A coinsurance and hospital costs
Medicare Part B coinsurance or copayments
First three pints of blood each year
Part A hospice care coinsurance
Skilled nursing facility coinsurance
Foreign travel emergency care (for some plans)
What Isn’t Covered by Medigap
Medigap policies generally don’t cover:
Prescription drugs (you’ll need a separate Part D plan)
Dental, vision, or hearing care
Long-term care or private-duty nursing
When Can You Enroll?
The best time to buy a Medigap policy is during your Medigap Open Enrollment Period, which starts the month you’re 65 or older and enrolled in Medicare Part B.
During this six-month window:
You can buy any plan sold in your state.
You can’t be denied coverage or charged more because of preexisting conditions.
After this period, you may still be able to buy a policy, but it could be more expensive or require medical underwriting.
What Does It Cost?
Premiums vary based on:
The insurance company
Your location
The specific plan you choose
Whether your premiums are “community-rated,” “issue-age-rated,” or “attained-age-rated”
Keep in mind: Medigap plans charge a monthly premium in addition to your Medicare Part B premium.
The Bottom Line
Medigap can be financially helpful by limiting your out-of-pocket healthcare costs and ensuring predictable expenses in retirement. If you travel often, value flexibility in choosing providers, or want help covering deductibles and coinsurance, a Medigap policy might be worth exploring.
As always, reviewing your options with an advisor or licensed insurance professional can potentially ensure that your plan fits your healthcare and financial goals.