Medicare Advantage vs. Medigap: Complete Comparison Guide

Medicare Advantage plans are offered by private insurance companies approved by Medicare. When you enroll, you leave Original Medicare and receive all your Part A and Part B benefits through the private plan. Most plans also include Part D drug coverage and extras like dental, vision, and hearing.

Medicare Advantage plans use provider networks (HMO, PPO, or other types). HMO plans require you to use in-network providers and get referrals for specialists. PPO plans let you go out-of-network at higher cost without referrals.

The appeal of Medicare Advantage includes low or $0 premiums, maximum out-of-pocket limits that cap your annual exposure, and extra benefits Original Medicare doesn't provide. The trade-off is network restrictions and potentially higher per-service costs.

Medigap (Medicare Supplement) plans supplement Original Medicare by paying some or all of the out-of-pocket costs Medicare leaves you responsible for—the Part A deductible, Part B coinsurance, and other gaps. You keep Original Medicare and use Medigap as secondary insurance.

With Medigap, you can see any doctor or hospital that accepts Medicare, anywhere in the United States. There are no networks, no referrals, and no prior authorization. If Medicare covers a service, your Medigap plan pays its share automatically.

Medigap plans have higher monthly premiums but provide cost predictability. With popular plans like Plan G, you know exactly what you'll pay each year—your premium plus the Part B deductible. There are no surprise copays or bills.

Medicare Advantage often wins on monthly premium—many plans cost $0 beyond your Part B premium. But you'll pay copays for doctor visits, coinsurance for procedures, and potentially significant costs for hospital stays until you reach your out-of-pocket maximum.

Medigap has higher premiums ($100-$300+ monthly) but minimal ongoing costs. With Plan G, for example, you pay only the annual Part B deductible ($240 in 2025) and then nothing more for Medicare-covered services. No copays, no coinsurance, no surprise bills.

Which costs less overall depends on how much healthcare you use. Healthy people who rarely see doctors may pay less with Medicare Advantage. Those with chronic conditions or frequent healthcare needs often find Medigap more affordable despite higher premiums.

Medigap provides maximum flexibility. See any Medicare doctor, use any Medicare hospital, visit specialists without referrals, travel anywhere in the country without worrying about networks. This freedom appeals to those who value choice and have established provider relationships.

Medicare Advantage requires more navigation. You need to check whether providers are in-network, get referrals for specialists (with HMO plans), and may need prior authorization for certain procedures. Going out-of-network (when allowed) costs significantly more.

For travelers and snowbirds, Medigap's nationwide portability is often decisive. Medicare Advantage plans focus on local networks and typically cover only emergency care when traveling. If you spend significant time in multiple locations, Medigap provides peace of mind.

Switching from Medigap to Medicare Advantage is easy—you can do it during any Annual Enrollment Period. Your Medigap coverage ends when your Medicare Advantage plan begins.

Switching from Medicare Advantage to Medigap is riskier. Outside your initial Medigap Open Enrollment Period (the 6 months when you're 65+ and first enrolled in Part B), insurers can deny you or charge higher premiums based on health conditions. Some states offer protections, but many don't.

This asymmetry is important: it's easier to go from Medigap to Medicare Advantage than the reverse. If you're unsure, starting with Medigap while you're healthy preserves future options.