Still Working at 65?
Whether you need to enroll in Medicare right now depends entirely on the size of your employer. Here's exactly what you need to know before you decide.
Get My Free Consultation → 📞 (888) 564-2326If you’re still working at 65 and covered by a group health plan, whether you need to enroll in Medicare right now is one of the most commonly misunderstood rules in the entire program. Get it wrong, and you could face a permanent late-enrollment penalty — or pay for coverage you didn’t need yet. The answer comes down to a single number: how many employees your employer has.
The size of your employer determines which plan pays first — called the “primary payer” — and that single fact changes everything about your enrollment decision. This count includes full-time, part-time, and seasonal employees across all of the employer’s locations.
Your employer plan pays first, Medicare pays second. You can safely delay Part B without penalty as long as you remain actively employed and covered.
Medicare pays first. You generally need to enroll in Medicare during your Initial Enrollment Period regardless of your employer coverage, or your employer plan may pay little or nothing on unpaid claims.
If your employer has 20+ employees and you delayed Part B, you get an 8-month Special Enrollment Period once you stop working or lose that coverage — whichever happens first. You have the full 8 months to enroll in Part A and Part B, but only the first 2 months of that window to also enroll in a Medicare Advantage or Part D plan.
⚠ Exception: If your employer coverage ends during your Initial Enrollment Period (the 7-month window around your 65th birthday), you don’t get a separate SEP — you’re already covered by your IEP instead.
This catches more people off guard than almost any other Medicare rule.
⚠ Critical: COBRA and retiree health coverage are not considered coverage based on current employment. Neither one qualifies you for a Special Enrollment Period. If you rely on COBRA after leaving your job and don’t enroll in Medicare during your correct window, you can face a permanent late-enrollment penalty when you eventually do enroll.
If you or your employer contribute to a Health Savings Account (HSA), this detail matters a great deal. Once you’re enrolled in any part of Medicare — including Part A — you can no longer contribute to an HSA, even if that Part A coverage is completely free.
What this means: If you want to keep contributing to your HSA past 65, you’ll need to delay enrolling in Part A too, not just Part B. Talk with your employer’s benefits department and a Medicare advisor before your 65th birthday to time this correctly.
How do I find out how many employees my company has?
Ask your HR or benefits department directly — they can confirm the employee count used for Medicare coordination-of-benefits purposes, which includes full-time, part-time, and seasonal employees across all company locations.
What if my coverage is through my spouse’s employer, not my own?
The same 20-employee rule applies based on your spouse’s employer size, as long as your spouse is still actively working and you’re covered as a dependent on their current employer plan.
Can I have both Medicare and my employer plan at the same time?
Yes — many people enroll in premium-free Part A at 65 since it costs nothing, while keeping their employer plan as primary. Just be aware of the HSA contribution issue above if that applies to you.
Is there a cost to get help figuring out my specific situation?
No. Our consultations are always free, with no obligation. We’re compensated by the insurance carrier when you enroll, at no additional cost to you.
⚠ Disclaimer: This information is for educational purposes only and is not a complete description of enrollment rules. Employer plan rules vary — confirm your specific situation with your benefits department and a licensed Medicare agent. NISONA is an independent insurance agency and is not affiliated with Medicare or the Social Security Administration.
No pressure. No obligation. We’ll help you confirm exactly what applies to your situation — and make sure you don’t miss your window.
Nisona serves the insurance needs of the Treasure and Space Coast.