Every fall, millions of Americans on Medicare get buried in glossy mailers promising free dental, vision, and grocery cards.
The fight between Medicare Advantage and Medicare Supplement plans is one of the most expensive decisions retirees make, and the marketing around it is engineered to confuse.
Which one actually protects your wallet depends on details the ads tend to skip.
Medicare Advantage, often called Part C, is run by private insurers paid by the government.
Premiums can be as low as zero dollars beyond your standard Part B charge, and the extras are real: dental, hearing, gym memberships, sometimes a debit card for over-the-counter items.
Roughly half of eligible Medicare beneficiaries now choose Advantage plans.
Advantage plans use networks, prior authorizations, and copays that can climb fast.
A hospital stay, a specialist referral, or a cancer diagnosis can trigger costs that a Supplement holder never sees.
Insurers also can change their networks and formularies every year, so the plan you picked can quietly morph into something else.
Medicare Supplement plans, also called Medigap, work differently.
You pay a monthly premium that's often $100 to $250 or more depending on your state, age, and plan letter.
In exchange, the plan picks up most or all of the costs traditional Medicare doesn't cover.
You see any provider who accepts Medicare, which is most of them.
Here's the part that stings: Medigap is priced by private insurers too, and those premiums rise over time.
A 65-year-old who locks in a low rate can face steep increases by 80.
Insurers in most states can also deny you coverage or charge more later if you try to switch from Advantage back to Medigap after your initial enrollment window closes.
You can usually move from Medigap to Advantage easily.
Going the other direction can be nearly impossible without passing medical underwriting.
A few states, including New York and Connecticut, offer more flexibility, but most don't.
Insurers on both sides, plus the brokers and call centers earning commissions on every switch.
Some agents earn more for enrolling you in one product than another, and that incentive shapes the advice you get.
The federal government saves money when people choose Advantage, which is one reason the plans get generous subsidies.
If you have significant health issues, travel often, or want predictable costs, Medigap plus a standalone drug plan is often the safer financial bet, even with the higher premium.
If you're relatively healthy, live near good in-network doctors, and want to keep monthly costs low, Advantage can work, but go in expecting to read the annual notice of changes every single year.
Either way, check whether your doctors and hospitals are actually in network, not just listed.
Confirm what prior authorization looks like for the care you're likely to need.
And ask any broker, in writing, how they get paid.
The real trap isn't picking the wrong plan once.
It's not understanding that one door locks behind you and the other doesn't.
Final Thoughts
Decide accordingly, and don't let a grocery card make the choice for you.