If you are turning 65 this year, you have about seven months to make one of the most expensive decisions of your retirement.
And the mail has already started arriving.
The choice comes down to two very different paths.
You can go with Medicare Advantage, the all-in-one plans from private insurers that often advertise $0 premiums and extras like dental and gym memberships.
Or you can stick with Original Medicare and add a Medigap supplement, which charges a monthly fee but covers most of what Medicare leaves behind.
The price gap looks obvious at first glance.
An Advantage plan might cost you nothing beyond the Part B premium most people already pay.
A supplement can run $100 to $250 a month or more, depending on your state, age, and tobacco use.
That difference adds up to thousands a year, and it is why roughly half of eligible Americans now pick Advantage.
But the cheap plan is not always the cheaper plan.
Advantage plans come with networks, prior authorizations, and annual out-of-pocket maximums that can reach $9,000 or more for in-network care.
A supplement typically has no network and, depending on the letter, can leave you with almost no copays for covered care.
The catch is that switching later is the hard part.
In most states, you get a one-time window to buy a supplement without answering health questions.
Miss it, and an insurer can charge you more or turn you down because of a diagnosis as common as diabetes or arthritis.
Advantage lets you change plans every year, but that flexibility runs only one direction.
There is one group that should look hard at Advantage: people who rarely see doctors, take few prescriptions, and want to keep monthly costs low.
If your health is stable and you can live inside a network, the savings are real.
Everyone else should run the math on a bad year, not a good one.
Add up the premium plus the worst-case out-of-pocket limit for each option.
Then check whether your doctors and hospitals are actually in the Advantage network, and whether your prescriptions sit on the formulary.
Call your pharmacy and ask what a 90-day supply would cost under each plan.
A few practical moves before you decide: read the Annual Notice of Change that arrives each fall, since formularies and networks shift every January.
Use the Medicare Plan Finder at medicare.gov to compare plans by your actual drug list.
And if you are still working past 65 or covered by a spouse's plan, ask before you enroll in anything.
Your initial enrollment window runs seven months around your 65th birthday.
Miss it without other qualifying coverage, and you can face lifetime late penalties on Part B and Part D.
The honest takeaway: Advantage is not a scam, and supplements are not a luxury.
They are two different bets on your future health.
The people who get hurt are the ones who pick on premium alone and discover the difference during a hospital stay.
Final Thoughts
Spend an afternoon with the numbers now, while you still have the choice.