If you're turning 65 this year, your mailbox is probably stuffed with promises.
One pile says Medicare Advantage gives you dental, vision, and a $0 premium.
Another says Medigap supplements let you see any doctor you want.
Both pitches leave out the part that hits your wallet hardest.
Medicare Advantage is an all-in-one plan run by private insurers that replaces Original Medicare.
Medigap, also called a Medicare Supplement, is extra coverage you buy to fill the gaps Original Medicare leaves behind, like the 20% coinsurance on doctor visits.
Advantage plans often advertise $0 monthly premiums, which feels like a win.
But you still pay your Part B premium, and the real cost shows up at the doctor's office through copays, deductibles, and annual out-of-pocket maximums that can run past $8,000.
You pay a higher monthly premium, often $100 to $200 or more depending on your state and plan letter.
In return, most plans cover nearly all of that 20% coinsurance, so a hospital stay or cancer treatment doesn't wreck your budget.
Advantage plans usually use HMOs or PPOs, meaning referrals, in-network doctors, and prior authorizations.
A recent government report found some plans denied prior authorization requests at higher rates than others, and denials can delay care you thought was covered.
If a provider accepts Medicare, they take your supplement.
That flexibility matters if you travel, snowbird in another state, or have a specialist you refuse to give up.
You get a one-time Medigap open enrollment window that starts when you're 65 and enrolled in Part B.
During that window, insurers can't reject you or charge more for health problems.
Miss it, and you can be denied or priced higher in most states.
You can switch or join during the annual enrollment period each fall, and you generally can't be turned down for pre-existing conditions.
That flexibility is why roughly half of eligible Medicare beneficiaries now pick Advantage.
If you're healthy and want low fixed costs, Advantage can work.
If you have chronic conditions, take expensive drugs, or want predictable bills, a supplement often costs less overall even with the higher premium.
One more thing people forget: drug coverage.
With Original Medicare plus a supplement, you buy a separate Part D plan, which adds another monthly premium and its own deductible.
Add up premiums, then estimate copays for your actual prescriptions and doctors.
A free counselor through your State Health Insurance Assistance Program can walk you through it with no sales pitch.
The mailers won't tell you this, but the honest answer is that neither option wins for everyone.
Final Thoughts
Your health, your doctors, and your tolerance for surprise bills should drive the choice, not the flashiest envelope in the stack.