Medicare Open Enrollment Ends Dec. 7: Mistakes to Avoid (and Why You Should Be Wary of Medicare Advantage)

The calendar says fall. For millions of households, it also says paperwork season. Medicare open enrollment ends Dec. 7. That can feel like a dry subject until a favorite doctor vanishes from a network. Or until a prescription costs far more in January. A little checking now can prevent a very expensive surprise later.

Medicare’s Annual Enrollment Period runs from October 15 through December 7. During that window, you can change Medicare Advantage plans and Part D drug plans. New coverage begins January 1. You do not have to change every year. But assuming last year’s plan will work the same is an easy trap.

Medicare Open Enrollment Ends Dec. 7: Start With What Changed

Before you look at any shiny new plan ad, find your Annual Notice of Change. It usually arrives in the mail in the fall. It has all the charm of a takeout menu written by lawyers. Read it anyway.

Plans can change premiums, deductibles, copays, drug lists, pharmacy networks, and doctor networks every year. A plan that suited you this year may add a deductible. It may move your medication to a pricier tier. It may drop your neighborhood pharmacy as a preferred option.

If you are helping a parent, spouse, or neighbor, focus on what they actually use. Their doctors, prescriptions, specialists, and pharmacy matter more than a long list of extras.

A Stern Warning About Medicare Advantage

Let me be blunt here. You will see a lot of Medicare Advantage ads this season. They promise $0 premiums, dental, vision, and grocery cards. Those ads are selling the price tag. They are not selling the coverage you will lean on when you are sick.

Medicare Advantage, also called Part C, is not Original Medicare. It is a private insurance plan that replaces it. The company, not Medicare, sets the rules for your care. Those rules can cost you dearly at the worst possible moment.

Here is what the glossy mailers tend to skip.

Your doctors may not be covered. Original Medicare lets you see any provider in the country who accepts Medicare. Medicare Advantage plans use networks. Step outside the network and you may pay much more. This hits hardest if you travel, winter somewhere else, or live in a rural area.

You may need permission before you get care. Many Medicare Advantage plans require prior authorization. That means the insurer must approve certain services before you receive them. Specialist visits, hospital stays, imaging, and some drugs are common examples. A denial or delay can hold up care when you can least afford to wait. Original Medicare rarely works this way.

Your drug costs are not guaranteed to be lower. Original Medicare does not include drug coverage. You add a separate Part D plan. Most Medicare Advantage plans bundle drug coverage in. But the plan’s drug list, tiers, and preferred pharmacies decide what you pay. A drug can sit on a high tier or need approval. Check each of your prescriptions by name and dose.

The $0 premium is not $0. You still pay your Part B premium. Then you pay copays, coinsurance, and deductibles whenever you use care. Plans do have a yearly out-of-pocket limit for in-network care. In 2026, that limit can be as high as $9,250. That is a lot of money for a healthy-looking plan.

Medigap does not work with Medicare Advantage. Medigap, or Medicare Supplement, only pairs with Original Medicare. If you join Medicare Advantage, you give up the chance to use Medigap to cover those out-of-pocket costs.

Getting out may be harder than getting in. You can return to Original Medicare during open enrollment. You can also do it between January 1 and March 31 if you are in a Medicare Advantage plan. But buying a Medigap policy afterward is another story. Outside certain protected windows, insurers in most states can use medical underwriting. They may charge more, add waiting periods, or turn you down. Your best protection is a 12-month “trial right” after you first join. Miss it, and your health history can work against you.

Plans change, and not always for the better. Some plans leave service areas. Others trim benefits like dental or raise cost-sharing. The extras that drew you in can shrink or vanish the next year.

Medicare Advantage plans must cover the same basic services as Original Medicare. The difference is how you get them, who approves them, and what you pay. That fine print is where people get burned.

So how do you protect yourself?

• Do not let a $0 premium or a perk drive your choice.
• Check that your doctors and hospitals are in the exact plan.
• Look up every prescription by name and dose.
• Read the prior authorization rules.
• Add up the worst-case yearly cost, not just the monthly bill.
• Ask what happens if you want to switch back to Original Medicare.

I am not saying Medicare Advantage is wrong for everyone. Some people are happy with it. But it should be a clear-eyed choice, not a reaction to a mailer.

Mistake No. 1: Choosing a Plan Based on the Premium Alone

A $0 monthly premium sounds like a no-brainer. Sometimes it fits. But the premium is just one line on the receipt.

Look at the deductible, doctor visit copays, hospital costs, drug coverage, and yearly out-of-pocket limit. A low-premium Medicare Advantage plan may cost more when you need care. Paying more each month for benefits you will never use is no prize either.

Mistake No. 2: Forgetting to Check Every Prescription

Drug coverage can change even when the plan name stays the same. A medication can move to a higher tier. It can gain a prior authorization rule. It can drop off the list entirely. Brand-name drugs, specialty drugs, insulin, and monthly medications deserve extra attention.

Make a list with the exact drug name, dosage, how often you take it, and your pharmacy. Then compare estimated costs under each plan. Do not trust a TV commercial promising low drug prices. Your own list tells the real story.

Also check whether your pharmacy is preferred, standard, or out of network. Two plans can cover the same medicine and charge very different prices at the same counter.

Here is some context for 2027. The yearly cap on Part D out-of-pocket drug costs rises to $2,400, up from $2,100. The standard deductible rises from $615 to $700. A temporary federal Part D premium subsidy also ends early. Your costs may change even if your plan did not.

Do Not Assume Your Doctors Are Included

Provider networks deserve the same attention as prescriptions. Do you want to keep a primary care doctor, cardiologist, therapist, or hospital? Verify that they take the exact plan you are considering for next year.

This matters most with Medicare Advantage, which often uses local networks. Some plans require you to stay in network except in emergencies. Others allow out-of-network care but charge more. An HMO and a PPO are not just alphabet soup. They affect referrals and what happens when you see an outside doctor.

Do not stop at the plan directory. Directories can be out of date. Call the doctor’s office and name the plan precisely. Ask whether they expect to be in network next year. A few minutes on the phone can save a painful switch later.

Mistake No. 3: Letting Dental, Vision, or Grocery Perks Make the Decision

Extra benefits can be useful. Dental allowances, eyewear, gym memberships, rides, and over-the-counter credits can make life easier. But they should be the cherry on top, not the whole sundae.

A generous dental benefit is a poor trade if the plan covers your medications badly. It is also a poor trade if it forces you to leave trusted doctors. Read the rules behind each extra. Check annual limits, participating providers, item restrictions, and what happens to unused credits.

The best plan usually handles the big basics well. That means medical care, prescriptions, access to providers, and protection from major costs. The free toothpaste is nice. It just should not be driving the bus.

Know Which Medicare Changes You Can Make

Open enrollment is not a magic do-over for every part of Medicare. During this window, you can generally do the following:

• Switch from Original Medicare to a Medicare Advantage plan.
• Move from one Medicare Advantage plan to another.
• Return from Medicare Advantage to Original Medicare.
• Join, drop, or change a Part D drug plan.

Medigap works differently. Depending on where you live and your situation, buying a policy later can mean underwriting, higher prices, or no offer at all. Do not assume leaving Medicare Advantage lets you buy any Medigap policy at the best price.

Weigh any move between Original Medicare and Medicare Advantage with care. Original Medicare plus a Part D plan and a Medigap policy usually means broader provider access. Medicare Advantage bundles services under a different cost structure and network rules. There is no universal winner. Your health, budget, travel habits, and local plan options all matter.

Mistake No. 4: Waiting Until December 7 to Begin

December 7 is the deadline, not the ideal day to start. Last-minute shopping leaves little time to compare details or fix a mistake. It is also stressful if you are helping a family member with many prescriptions and specialists.

Give yourself a few short sessions. First, gather your medications, doctors, pharmacies, and current plan papers. Next, compare your options. Finally, review your choice before you submit anything. Decision fatigue is real, and it loves a deadline.

Once you enroll, save your confirmation number and any emails. If you can, call the plan to confirm your start date and coverage. Keep a simple folder for everything. Future you will say thanks.

Be Careful With Sales Calls and Too-Good-To-Be-True Promises

Medicare marketing gets loud this time of year. A friendly voice may promise bigger benefits, money back, or a plan that “covers everything.” Treat a high-pressure pitch like a suspicious casserole at a potluck. Proceed with care.

Never give your Medicare number, Social Security number, or bank details to an unexpected caller. Be wary if someone says a benefit will vanish unless you act right now. Real choices deserve time to read the details.

For free, unbiased help, try your State Health Insurance Assistance Program, known as SHIP. You can also call 1-800-MEDICARE or visit Medicare.gov. A trusted family member or local counselor can sit with you, too. A second set of eyes is smart, not needy.

Before you decide, run this quick reality check:

• Are your doctors, hospitals, and pharmacy included?
• Are all your prescriptions covered at a cost you can handle?
• Have you compared the deductible, copays, and yearly out-of-pocket limit?
• Do the plan’s rules fit your travel, specialist, and referral needs?
• If it is Medicare Advantage, do you know how hard it may be to get back out?
• Did you save proof of enrollment before the deadline?

The goal is not to find the flashiest plan in the pile. It is to choose one that keeps ordinary life simple when things get complicated. Put on the kettle and gather the paperwork. Give yourself an unhurried hour or two before December 7. That small bit of homework can make January feel a lot less like a pop quiz.