I have a confession. In my head, I'm still 37.

The calendar disagrees. I'm 64 and still working, and I finally had to give in to age and start learning how Medicare works.

I'm still learning. But here's what I've figured out so far, because Medicare open enrollment starts Oct. 15, and a lot of people my age think that date is for us. It isn't.

Open enrollment is for people already on Medicare

Medicare's annual open enrollment runs Oct. 15 through Dec. 7. If you already have Medicare, that's your window to join, drop or switch a Medicare Advantage or drug plan. Changes take effect Jan. 1.

If you're just turning 65, you have your own window. Medicare says your first chance to sign up starts three months before the month you turn 65 and ends three months after it.

Still working at 65? This is the big one

I'm a radio lifer. There's no end in sight for me, and I'm on my company's health plan. So do I have to sign up at 65?

It depends on the size of your employer.

According to a fact sheet from the federal Centers for Medicare & Medicaid Services, if your employer has 20 or more employees, you can generally stay on the work plan and put off Part B, the part with the monthly premium. If your employer has fewer than 20 employees, Medicare becomes your primary coverage and you should sign up at 65.

Medicare's own advice is to ask the employer that provides your insurance what you need to do when you turn 65. That's worth a call to your benefits office.

What happens if you get it wrong

This is the stomach-drop part. If you were supposed to sign up for Part B and didn't, the penalty is a 10% increase in your premium for every 12 months you went without it. And you pay it for as long as you have Part B.

The good news for those of us still working: once you stop working or lose that coverage, you get an eight-month special enrollment period to sign up without a penalty.

One more catch. If you put money into a health savings account, Medicare says you and your employer should stop contributing six months before you retire or apply for Social Security.

SEE ALSO: Stay NJ after the cuts: Who qualifies and how much you can get

Planning to travel in retirement? Medicare usually doesn't cover care outside the United States. | Photo by Danielle-Claude Bélanger on Unsplash
Planning to travel in retirement? Medicare usually doesn't cover care outside the United States. | Photo by Danielle-Claude Bélanger on Unsplash

The travel surprise

We want to get some traveling in before we get too old. So this one caught my eye: Medicare usually doesn't cover health care outside the United States, with a few exceptions. Something to plan for before you book the trip.

Free help in New Jersey

You don't have to figure this out alone. New Jersey's State Health Insurance Assistance Program, known as SHIP, offers free counseling from trained volunteers. The number is 1-800-792-8820.

I may be 37 in my head. But I'd rather learn this at 64 than pay for it at 70.

SEE ALSO: Social Security raise for 2027 is 3,6%. Here's what NJ retirees get 

The 10 best and 10 worst states to retire

For their 2024 report, Bankrate.com analyzed factors such as cost of living, health care and crime to rank the 50 states as places where you might want to consider retirement. Visit this link for the complete report.

Gallery Credit: Bankrate/New Jersey 101.5