Every fall, roughly 60 million Medicare enrollees get buried in glossy mailers promising free dental, free groceries, and zero premiums.
It usually isn't, and the difference between Medicare Advantage and a Medigap supplement can swing a household budget by thousands of dollars a year.
Original Medicare covers hospital and doctor visits but leaves you on the hook for 20% of most outpatient costs, with no annual cap.
A Medicare Supplement plan, also called Medigap, pays most of that leftover share in exchange for a monthly premium.
Medicare Advantage is a different animal entirely: private insurers replace Original Medicare, often with a $0 premium, but you inherit networks, prior authorizations, and copays that vary by plan and by county.
That $0 premium is the hook, and it's where the math gets uncomfortable.
Advantage plans frequently charge copays for hospital stays, scans, and specialist visits, and those costs can stack up in a bad year.
Medigap premiums run higher month to month, but once you're enrolled, the plan generally picks up its share no matter how large the bill gets.
There's a catch most people learn too late: Medigap enrollment is easiest during your initial Medicare window.
After that, in most states, insurers can review your health history and charge you more or turn you down.
Advantage plans, by contrast, accept nearly everyone during open enrollment.
That asymmetry explains why brokers push Advantage so hard.
They're typically paid a commission per enrollee, and switching plans each year can mean another commission.
Dental, vision, and hearing benefits on Advantage plans often cap out at a few hundred dollars a year, which doesn't go far at a real dentist's office.
Some plans offer over-the-counter allowances or grocery cards, but those amounts are modest and can change when the plan's contract renews.
Read the annual notice of change that arrives each fall.
It's boring, and it's where benefits quietly shrink.
Advantage plans use provider networks that shift year to year.
If your cardiologist drops out of the network in January, you're either paying out of network or finding a new doctor.
Medigap, paired with Original Medicare, lets you see any provider nationwide who accepts Medicare.
For snowbirds and anyone with a serious diagnosis, that flexibility is worth real money.
If you're healthy, take few prescriptions, and want the lowest possible monthly cost, Advantage can work — as long as you understand the ceiling on your risk.
If you have chronic conditions, travel often, or simply want to know your worst-case number, Medigap usually costs more upfront and less when it matters.
The honest answer is that neither is universally better, and anyone who tells you otherwise is probably selling something.
Before you decide, check three things: your doctors' current network status, your drug list under the plan's formulary, and the out-of-pocket maximum.
Then compare that maximum against a year of Medigap premiums.
That single comparison cuts through most of the marketing.
The uncomfortable truth is that the system rewards people who read paperwork and punishes those who don't.
Brokers, insurers, and marketers all profit from confusion, so the burden lands on you.
Final Thoughts
Spend an afternoon with a calculator and your actual prescriptions, and you'll make a better call than any mailer can.