Medicare Supplement vs. Medicare Advantage: What's the Difference?

Medicare · October 2026

Medicare Supplement vs. Medicare Advantage: What's the Difference?

Senior woman comparing two Medicare plan brochures at her table

By Ali El-Hallani, Principal, Michigan Benefit Services

When you turn 65, you will hear two terms over and over: Medicare Supplement and Medicare Advantage. They are two different ways to get help with the costs Original Medicare does not cover. Neither one is right for everyone. Here is how they compare, in plain English.

Medicare Supplement (Medigap)

A Medicare Supplement works alongside Original Medicare (Parts A and B). Medicare pays its share of your bill first, then your Supplement pays most or all of what is left, depending on the plan you choose, such as Plan G or Plan N. You can see any doctor or hospital in the country that accepts Medicare, with no network and no referrals. Supplements do not include drug coverage, so most people add a separate Part D plan.

Medicare Advantage (Part C)

A Medicare Advantage plan is offered by a private insurance company approved by Medicare. It replaces how you receive your Part A and Part B benefits, and most plans include Part D drug coverage. Many plans have low or $0 monthly premiums and include extras like dental, vision, or hearing. In return, you usually use the plan's network of doctors and pay copays as you go, up to a yearly out-of-pocket limit.

Side-by-side comparison

FeatureMedicare SupplementMedicare Advantage

Who runs itWorks alongside Original MedicareA private plan that replaces how you get Original Medicare benefits

Doctors and hospitalsAny provider in the U.S. that accepts MedicareUsually a network (HMO or PPO)

Monthly premiumTypically higherOften low, some $0 (you still pay Part B)

Costs when you get careLow and predictable, depending on the planCopays and coinsurance, up to a yearly limit

Yearly out-of-pocket limitDepends on the plan; Plan G leaves only the Part B deductibleYes; up to $9,250 in-network for 2026

Prescription drugsNot included; add a Part D planUsually included

Extra benefitsNot includedMany plans include dental, vision, or hearing

Referrals and approvalsNo referrals or prior authorization from the planMay require referrals or prior authorization

Switching laterMay require health questions after your first enrollment windowCan change each year during Annual Enrollment

Timing matters

Your best time to buy a Medicare Supplement is your Medigap Open Enrollment Period, the 6 months starting the first month you are 65 or older and enrolled in Part B. During that window, you cannot be turned down or charged more because of your health. After it ends, you may have to answer health questions. Medicare Advantage plans can be changed each year during Annual Enrollment, October 15 to December 7.

Which one fits you?

A Supplement may fit you if you want freedom to see any Medicare provider, predictable costs, or you travel often. Medicare Advantage may fit you if you want a lower monthly premium, drug coverage in one plan, and extra benefits, and you are comfortable using a network. We will look at your doctors, prescriptions, and budget and explain your options side by side. Call 313.721.2144.

We do not offer every plan available in your area. Currently we represent 5 organizations (Aetna, Humana, UnitedHealthcare, Molina Healthcare, and Devoted Health) which offer Medicare plans in your area. Please contact Medicare.gov, 1-800-MEDICARE (TTY 1-877-486-2048), or your local State Health Insurance Assistance Program (SHIP) to get information on all of your options. Michigan Benefit Services is not connected with or endorsed by the U.S. government or the federal Medicare program. Plan benefits, premiums, networks, and availability vary by plan and area. Sources: Medicare.gov, when to buy Medigap and KFF, Medicare Advantage in 2026.