If you're turning 65 this year, your mailbox is probably already stuffed with Medicare ads promising dental, vision, and a $0 monthly premium.
What those glossy brochures tend to leave out is the part where your costs can spike the moment you actually get sick.
The choice comes down to two very different paths: Medicare Advantage (Part C) or Original Medicare paired with a Medigap supplement.
They behave nothing alike when the bills arrive.
Medicare Advantage plans are run by private insurers.
You typically stay in a network, get extras like hearing aids or gym memberships, and often pay nothing upfront.
The trade-off is that each doctor visit, specialist, and hospital stay comes with copays and coinsurance that can stack up fast.
There's also an annual out-of-pocket maximum, which in 2024 can run as high as $8,850 for in-network care.
You keep Original Medicare, and a supplement policy picks up most of what Medicare doesn't cover.
Premiums are higher every month, but once you pay them, a hospital stay often costs you almost nothing.
You can see any doctor in the country who accepts Medicare, no referrals required.
The catch that trips up millions of Americans is timing.
You get a one-time, six-month Medigap open enrollment window that starts when you're 65 and enrolled in Part B.
During that window, insurers can't charge you more or deny you coverage because of your health history.
Miss it, and you may be stuck answering medical questions just to buy a policy.
That's why the Medicare Advantage pitch is so tempting at first.
It's cheap, it's simple, and it doesn't ask about your diabetes or heart condition.
But a 2023 KFF analysis found that a meaningful share of Advantage enrollees switch back to Original Medicare within a few years—and many discover they can't get a Medigap plan anymore because of underwriting.
If you're healthy, live near a strong provider network, and want low premiums, Advantage can work well.
If you have ongoing conditions, travel a lot, or simply want predictable costs, Medigap plus a Part D drug plan is often the safer long-term bet.
The monthly premium stings, but the financial ceiling is lower.
One more thing: Advantage plans change every year.
Networks shrink, formularies shift, and copays creep up.
You have to review your plan each fall during open enrollment, or you may find your doctor dropped from the network in January.
The honest takeaway is that the cheapest option today is rarely the cheapest option over ten years.
Run the math on your actual prescriptions and likely doctor visits, not the brochure's best-case scenario.
Final Thoughts
And if you can qualify for Medigap during your open window, think hard before letting it close.