Can I have both Medigap and Medicare Advantage at the same time?

No. Federal law prohibits insurers from selling you a Medigap policy if you are enrolled in a Medicare Advantage plan. You must choose one path or the other.

Does Medicare Advantage cost less than Medigap?

Medicare Advantage plans often have lower or $0 monthly premiums, but they typically have higher cost-sharing when you use services. Medigap has higher premiums but generally lower and more predictable out-of-pocket costs. Total spending depends on your health utilization.

If I switch from Medicare Advantage to Medigap, will I be accepted?

In most states, insurers can use medical underwriting when you apply for Medigap outside of a guaranteed-issue period, meaning they can decline your application or charge more based on health history. A few states have additional protections. Contact your state insurance department or a SHIP counselor for your state's rules.

When is the best time to enroll in Medigap?

The best time is during your Medigap Open Enrollment Period, which is the six-month window starting the month you are both 65 or older and enrolled in Medicare Part B. During this period, insurers must offer you any available Medigap plan at standard rates without medical underwriting.

Medigap vs Medicare Advantage: How to Choose

By Naomi Foster, Contributing Writer, Healthcare
Updated July 9, 2026

Compare Medigap costs.

Get a rough Medigap premium before you weigh it against an Advantage plan.

Open the calculator

Medigap and Medicare Advantage cannot be combined. Medigap works alongside Original Medicare (Parts A and B) to cover cost-sharing such as deductibles and coinsurance, while Medicare Advantage replaces Original Medicare with a private plan that often bundles extra benefits. The choice determines which doctors you can see, what you pay out of pocket, and how your coverage works when you travel.

What Is Medigap?

Medigap is private health insurance sold by state-licensed insurers to cover the cost-sharing gaps Original Medicare leaves behind. Plans are standardized by the federal government, so a Plan G from one insurer must offer the same core benefits as Plan G from any other. The full standardized plan chart is available at Medicare.gov's Medigap plan comparison tool.

Key features of Medigap:

Works with any doctor or hospital that accepts Medicare nationwide, with no network restrictions.
Covers cost-sharing such as the Part A hospital deductible, Part B coinsurance, and (with most plans) excess charges.
Requires you to keep paying your Part B premium in addition to the Medigap premium.
Does not include prescription drug coverage; you must enroll in a standalone Part D plan.
Carries higher monthly premiums than most Advantage plans, but out-of-pocket costs are more predictable.

What Is Medicare Advantage?

Medicare Advantage (Part C) is an alternative way to receive your Medicare benefits through a private insurer approved by the Centers for Medicare and Medicaid Services (CMS). Plan availability and star ratings are searchable at Medicare.gov.

Key features of Medicare Advantage:

Often includes HMO or PPO networks that restrict which providers are covered at in-network rates.
Frequently bundles Part D drug coverage along with dental, vision, and hearing benefits.
Typically has lower monthly premiums than Medigap, but out-of-pocket exposure can be substantial (annual maximums can reach several thousand dollars).
Coverage outside your area is usually limited to emergencies.
Plans can change benefits, premiums, and formularies each year.

Side-by-Side Comparison

Feature	Medigap	Medicare Advantage
Works with Original Medicare	Yes	No (replaces it)
Provider network	Any Medicare-accepting provider	Usually network-restricted
Monthly premium	Higher	Often lower (or $0)
Out-of-pocket predictability	High (most cost-sharing covered)	Variable (annual OOP max applies)
Prescription drugs	Separate Part D plan needed	Usually bundled
Extra benefits (dental, vision)	Rarely	Commonly included
Travel coverage	Nationwide	Emergency only (in most plans)
Annual plan changes	Benefits stable (premiums may rise)	Benefits and formularies can change yearly

Who Typically Benefits from Medigap?

Medigap tends to suit people who:

Travel frequently or split time between states and want nationwide provider access.
Have ongoing or complex medical conditions and prefer predictable out-of-pocket costs.
Want to see any Medicare-participating specialist without a referral (depending on plan type).
Can afford a higher monthly premium in exchange for minimal surprise bills.

Who Typically Benefits from Medicare Advantage?

Medicare Advantage may be a better fit for people who:

Are generally healthy and want to keep monthly premium spending low.
Live in one area year-round and are comfortable with a local provider network.
Want bundled benefits like dental and vision in a single plan.
Are willing to review their plan each Annual Enrollment Period (October 15 through December 7) to make sure it still fits.

Switching Between the Two

If you enroll in Medicare Advantage first and later want to switch to Medigap, you may face medical underwriting in most states. Insurers can review your health history and decline your application or charge higher premiums outside of guaranteed-issue situations. This contrasts with your initial Medigap Open Enrollment Period, the six-month window starting the month you turn 65 and enroll in Part B, during which insurers must sell you any plan at standard rates regardless of your health. The Medigap cost calculator can help you estimate costs before you commit.

How to Verify and Get Help

Medicare rules are detailed and subject to change. Verify plan specifics at Medicare.gov and consider speaking with a State Health Insurance Assistance Program (SHIP) counselor, who provides free, unbiased guidance. CMS publishes enrollment and coverage data at CMS.gov.

Cost Structures: Premiums, Deductibles, and Out-of-Pocket Maximums

One of the clearest differences between Medigap and Medicare Advantage is how costs are structured across the year. With Medigap, you pay a fixed monthly premium. In return, the plan covers most or all of Medicare's cost-sharing, so bills after receiving care are minimal or zero depending on the plan. Annual spending becomes fairly predictable, which matters to people on fixed incomes.

With Medicare Advantage, you may pay a lower or $0 monthly premium, but the plan charges copays, coinsurance, and deductibles each time you use services. Every Medicare Advantage plan must cap your annual out-of-pocket spending at a federally set maximum (which in 2026 can be as high as $9,250 for in-network services, per CMS's mandatory Medicare Advantage out-of-pocket maximum (cited in KFF's 2026 Medicare Advantage analysis)). In a high-use year, you could reach that cap. Knowing that ceiling is important when comparing the two approaches.

Prescription Drug Coverage

Medigap plans do not cover prescription drugs. If you choose Medigap, you must separately enroll in a Medicare Part D plan. Part D plans vary in formulary, premiums, and pharmacy networks.

Most Medicare Advantage plans bundle Part D coverage, which can simplify administration. However, if a plan's formulary does not cover your medications well, drug costs can be high even when the monthly premium looks attractive. Check whether your specific medications appear on a plan's formulary before enrolling.

Stability and Annual Changes

Medigap benefits are standardized by federal law and do not change from year to year, though premiums can increase. A Plan G purchased today will offer the same core benefits a decade from now. Medicare Advantage plans can change their benefits, premiums, copays, provider networks, and drug formularies each January 1. You receive an Annual Notice of Change each fall and must review it to understand what your plan will look like the following year. Unfavorable changes can be addressed during the Annual Enrollment Period (October 15 through December 7).

For people who prefer stable, broad provider access, or who have complex medical needs, Medigap's consistency is a real practical advantage. For people comfortable with annual plan reviews and living in a single area, Medicare Advantage's lower premium and bundled extras can make sense.