If you are approaching 65 and still enjoying your career, first of all, congratulations! Many of our neighbors in Hendersonville and throughout Middle Tennessee are choosing to stay in the workforce longer. Whether it’s because you love what you do or you’re just not quite ready to trade the office for the golf course at Bluegrass Yacht & Country Club, working past 65 is the new normal.
However, staying employed past your 65th birthday adds a layer of complexity to your Medicare transition. The biggest question I hear at our workshops is: "Do I have to sign up for Medicare if I’m still working?"
The answer isn't a simple "yes" or "no." It’s "it depends." And if you get it wrong, the federal government has a way of reminding you: through lifelong monthly penalties.
I’m Nathan Wright, and I’ve spent over a decade helping folks navigate these exact waters. My goal today is to help you spot the "penalty traps" before you trip over them, so you can keep more of your hard-earned retirement savings where they belong: in your pocket.
Pitfall #1: The "Small Business" Trap (The 20-Employee Rule)
This is the most common mistake I see. Most people assume that if they have health insurance through their job, they can ignore Medicare. That is only true if your employer is large enough.
In the eyes of Medicare, the "magic number" is 20.
- If your employer has 20 or more employees: Your employer coverage is "primary." You can usually delay Medicare Part B without any late enrollment penalties.
- If your employer has fewer than 20 employees: Medicare is considered "primary." This means Medicare expects to pay first, and your work insurance pays second.
If you work for a small local business here in Tennessee with 15 employees and you don't sign up for Part B at age 65, you might find yourself in a nightmare scenario. Your employer plan might refuse to pay your hospital bill because they’ll say, "Medicare should have paid first." Even worse, when you eventually do sign up for Medicare, you could be hit with a permanent 10% penalty for every year you delayed.
Nathan’s Tip: Check with your HR department today and ask specifically, "How many employees does the CMS count for our group health plan?" Don't guess.

Pitfall #2: Thinking COBRA or Retiree Coverage Counts
I see this happen often during our Medicare workshops. Someone retires at 65, takes a COBRA plan or a retiree health package, and thinks they are safe from Medicare penalties because they still have "insurance."
This is a dangerous myth.
To delay Medicare Part B without a penalty, you must be covered by insurance based on current employment.
- COBRA is not current employment.
- Retiree coverage is not current employment.
If you rely on COBRA for 18 months after you retire and don’t sign up for Medicare Part B, you will likely face a lifelong late-enrollment penalty. You also might be stuck waiting until the General Enrollment Period (January through March) to even sign up, leaving you with a massive gap in coverage.
Pitfall #3: The HSA "Six-Month Lookback"
This is the "gotcha" that catches even the most prepared Tennessee seniors. If you are contributing to a Health Savings Account (HSA) at work, you need to be very careful about when you stop.
Once you enroll in any part of Medicare (even just Part A), you can no longer contribute to an HSA. But here’s the kicker: when you apply for Medicare or Social Security after age 65, Medicare Part A is often backdated by six months.
If you contribute to your HSA right up until the month you retire, you could accidentally end up with six months of "excess contributions," which leads to tax penalties from the IRS.
The Golden Rule: Stop all HSA contributions at least six months before you plan to enroll in Medicare or start taking Social Security.

Pitfall #4: Assuming Your Drug Coverage is "Creditable"
While you can often delay Part B if you work for a large company, Part D (prescription drugs) has its own set of rules. To avoid a Part D penalty later, your employer’s drug coverage must be "creditable." This is just a fancy way of saying it’s at least as good as a standard Medicare drug plan.
Every year, usually in October, your employer is required to send you a "Notice of Creditable Coverage."
- Keep these letters! If you eventually join Medicare at 68 or 70, the insurance company will ask for proof that you had creditable coverage.
- If your employer coverage isn't creditable and you don't get a separate Part D plan, you’ll be charged a penalty of 1% per month for every month you went without it. That stays with you for life.
Pitfall #5: Missing the 8-Month Special Enrollment Window
When you finally decide to hang up the "Gone Fishing" sign and leave your job, the clock starts ticking. You have an 8-month Special Enrollment Period (SEP) to sign up for Medicare Part B without a penalty.
However, don't wait 8 months! Most people want their Medicare to start the very first day their employer coverage ends so there is no gap. If you wait until month 7 to start the paperwork, you might be left paying 100% of your medical bills out of pocket for a few months while Social Security processes your application.
Is Staying on the Employer Plan Actually the Best Move?
Just because you can stay on your employer plan doesn't always mean you should.
Often, when we sit down with folks at our office on Harbor Drive, we find that the monthly premium they are paying for their "work insurance" is actually higher than what they would pay for Medicare and a Medicare Supplement (Medigap) plan.
Plus, employer plans often have high deductibles and copays. A good Medigap plan (like Plan G) could potentially lower your out-of-pocket costs significantly while giving you the freedom to see any doctor in the country that accepts Medicare.

Let’s Clear Up the Confusion Together
Medicare wasn't designed to be easy to understand. It was designed by the government, after all! But you don't have to navigate these rules alone. Whether you’re working for a big company in Nashville or a small shop in Hendersonville, the rules are the same, and the pitfalls are just as deep.
If you’re feeling overwhelmed by the "alphabet soup" of Parts A, B, C, and D: or if you’re worried about making a mistake that will cost you for the rest of your life: we are here to help. We are independent brokers. We don't work for the insurance companies; we work for you.
Our goal is to give you the answers you need to make an informed, pressure-free decision.
Download the free Medicare guide at medi65.com/book
