Medicare turns 65 into a paperwork birthday. Cards in the mail, junk calls from numbers you don’t recognize, and brochures from carriers you’ve never heard of. The pressure to do something fast is real, and that’s exactly when people make the wrong move.
We’ve helped thousands of clients through their first Medicare enrollment. The mistakes aren’t random. They cluster around the same five traps every year. Here they are, in the order we see them break people.
Mistake 1: Missing the Initial Enrollment Window
Your Initial Enrollment Period is a seven-month window. It opens three months before the month you turn 65, includes your birthday month, and runs for three months after. Miss it, and you can end up paying a Part B late enrollment penalty for the rest of your life. Not for a year. For the rest of your life.
The penalty is 10% of the standard Part B premium for every full 12 months you delayed signing up when you should have. That’s permanent. It rides with you until the end.
There are legitimate reasons to delay, mostly involving still being on a creditable employer group health plan past 65. But “I forgot” and “I thought I had more time” and “the brochures stacked up and I didn’t get to it” are not on the list. If you’re approaching 65 and you don’t have an active group plan from a job, set a calendar reminder for three months before your birthday month. Open the window. Start the conversation.
Real example: Hank in Lakeland turned 65 in March. He was retired, no employer coverage, but his wife told him “we’ll figure it out later.” Later turned out to be August. By the time we got him enrolled, he had to wait for the General Enrollment Period in the following January-to-March, which meant coverage didn’t start until July of the next year. That’s roughly 15 months uninsured. And the late penalty followed him for life.
Mistake 2: Ignoring Drug Coverage Until You Need It
Part D is prescription drug coverage. It’s separate from your medical coverage under Original Medicare. A lot of people skip it because they’re healthy at 65 and not on any meds. The logic feels solid. Why pay for drug coverage I don’t use?
Here’s the trap: if you go more than 63 days after your Initial Enrollment Period without creditable prescription drug coverage, you get hit with a Part D late enrollment penalty. Like the Part B one, it’s permanent. The penalty is 1% of the national base beneficiary premium per month you went without coverage, and it gets added to your Part D premium every month for the rest of your life.
Twelve months uncovered? 12% surcharge, forever. Five years uncovered? 60% surcharge, forever. By the time you actually need expensive medication, you’re paying inflated premiums on top of the meds.
A basic, low-cost Part D plan is usually cheap enough that the penalty avoidance alone justifies it. Get a plan, even a minimal one, during your IEP.
Mistake 3: Picking the Wrong Part D Plan
When people do enroll in Part D, the most common mistake is picking based on premium. Lowest monthly premium wins, right?
Not even close. Part D plans have wildly different formularies. The formulary is the list of drugs the plan covers and what tier each one falls into. Tier 1 generics might be a few dollars. Tier 4 specialty drugs might be hundreds. The same medication can be Tier 2 on one plan and Tier 4 on another.
The right way to pick a Part D plan is to take your current medication list — every single prescription you take regularly, with exact dosage — and run them through the actual formularies of three or four plans available in your county. Total annual cost is what matters, not monthly premium. A $0-premium plan that doesn’t cover your maintenance medication can cost thousands more per year than a $40-premium plan that does.
This is one of the highest-leverage hours of your year. Sit down with someone who can pull the formularies, plug in your meds, and show you actual projected costs.
Mistake 4: Defaulting to Whatever Your Mom Had
This one is more human than technical, but it derails enrollments constantly. People assume the plan a parent or older sibling has must be the right plan for them because that family member has been on Medicare a while and “knows the ropes.”
Three problems with this. One, Medicare Advantage plan availability is by county. The plan your mom has in Sarasota County may not even exist in Hillsborough County. Two, plan networks and benefits change every year — what was great in 2021 might be mediocre in 2026. Three, your medical situation, your medications, and the doctors you want to keep are not your mom’s.
Use your family as a sanity check on what working with an advisor felt like for them. Don’t use them as a plan recommendation engine.
Mistake 5: Not Comparing Medicare Advantage Plans Every Year
If you choose a Medicare Advantage plan, your work is not done. Every fall, between October 15 and December 7, is the Annual Election Period. This is when carriers can change premiums, copays, drug formularies, provider networks, and supplemental benefits like dental and vision.
The plan you picked last year might be a great plan this year, or it might have quietly added a new copay structure that costs you an extra $1,200. The only way to know is to compare.
Carriers do not call you in October to say “hey, your plan got worse, want to look around?” They send a thick envelope called the Annual Notice of Change, which most people throw out without reading. Read it. Or have an advisor read it with you. Every year.
What This Means for You
Medicare looks simple from the outside and gets complicated fast once you’re in it. The five mistakes above account for the overwhelming majority of preventable pain we see in the first year. Sidestep them, and you’re already ahead of most new enrollees.
Two action items if you’re approaching 65 or in your first year on Medicare:
- Confirm your dates. Know your IEP window, your AEP window, and your plan’s renewal date.
- Get an annual review on the calendar. Once a year, every year, sit down with an advisor and look at your plan. It takes an hour. It can save thousands.
Carrier-independent advisors don’t work for any single insurance company. We can put Aetna, Humana, UnitedHealthcare, BlueCross and the rest on one comparison and tell you which actually fits your situation. That’s a real review. Not a sales pitch dressed up like one.
Want a real conversation about this? Book a Healthcare Review — one hour, free, plain English.