If you're turning 65 or already on Medicare, you've probably seen the ads promising dental, vision, and grocery money with Medicare Advantage plans.
What those commercials don't mention is that the other option, a Medicare Supplement, works completely differently.
Choosing between them is one of the biggest financial decisions retirees make, and picking wrong can cost thousands of dollars a year.
Original Medicare pays 80% of most covered costs, and you pay the other 20% with no cap.
A Medicare Supplement, also called Medigap, is a private plan that picks up most or all of that leftover 20%.
Medicare Advantage is different: the government pays a private insurer to cover you instead, usually through an HMO or PPO, often with $0 premiums but copays and networks attached.
The tradeoff comes down to premiums versus surprise bills.
Medicare Advantage tends to have low or zero monthly premiums, but you can face copays for doctor visits, hospital stays, and specialist care, plus an annual out-of-pocket maximum that's often several thousand dollars.
Medigap plans usually cost more each month, but once you pay the premium, your costs are far more predictable.
There's a catch that trips up a lot of people: the best time to buy a Medigap plan is during your six-month Medigap Open Enrollment window that starts when you're 65 and enrolled in Part B.
During that window, insurers generally can't reject you or charge more because of health conditions.
Miss it, and in most states you can be turned down or charged a higher rate.
Switching later can be tough for the same reason.
If you start with Medicare Advantage and develop a health problem, moving to a Medigap plan in most states may mean answering health questions and risking denial.
Some states have protections that make switching easier, but rules vary widely, so it's worth checking what your state allows before you decide.
Medicare Advantage isn't automatically a bad deal.
If you're healthy, rarely see specialists, and want a low monthly cost with extras like dental or hearing aid coverage, it can work well.
Just check two things before signing up: whether your doctors and hospitals are in the network, and what the plan's out-of-pocket maximum actually is.
That maximum is your worst-case number for the year.
Medigap tends to make more sense if you have ongoing health conditions, travel a lot, or simply want to see any provider who accepts Medicare without network headaches.
You'll pay more monthly, but you're buying predictability.
For many retirees on fixed incomes, knowing the ceiling on their health costs is worth the premium.
Medicare Advantage plans often bundle in Part D prescriptions, while Medigap does not, so you'd buy a separate Part D plan.
Compare the total cost, not just the premium, because a cheap plan with high drug copays can end up costing more than a pricier one.
Open Enrollment for Medicare Advantage and Part D runs from October 15 to December 7 each year.
If you're already on a plan, don't ignore the annual notice of change letter.
Formularies shift, networks shrink, and premiums move every year, even if you do nothing.
Our take: treat this like a budget decision, not a marketing one.
Add up premiums, worst-case out-of-pocket costs, and drug prices for each option, then pick the one your finances can actually absorb in a bad health year.
Final Thoughts
Cheap now can be expensive later, and it's much easier to lock in flexibility while you still qualify.