If you are over 65 and currently on employer health coverage, losing that coverage — whether through retirement, a layoff, or a change at your spouse's employer — triggers a Medicare Special Enrollment Period (SEP). This window lets you enroll in Medicare without paying the late enrollment penalty.
Why This SEP Exists
Many people delay Part B while working because their employer plan is primary. Medicare allows this delay — but only while the qualifying employer coverage is active.
How Long the SEP Lasts
You generally have 8 months from the month after employer coverage ends (or the month employment ends, whichever is first) to enroll in Part B and switch your coverage.
This is different from COBRA. COBRA does not count as "active" employer coverage for Medicare purposes. If you rely only on COBRA after 65, you may already be past your on-time enrollment window.
What You Can Do During This SEP
- Enroll in Medicare Part B without a late penalty.
- Enroll in a Medicare Advantage plan, or stay with Original Medicare.
- Enroll in a Part D prescription drug plan.
- In many cases, apply for a Medigap policy — sometimes with guaranteed-issue rights.
The Medigap Timing Detail
Medigap has its own rules separate from the Part B SEP. In Kentucky, Medigap purchases outside your Medigap Open Enrollment Period may be subject to medical underwriting. Certain situations (loss of employer coverage being one) may grant guaranteed-issue rights, but timing is strict.
Compare Medigap vs Medicare Advantage carefully — see Advantage vs Medigap.
Common Mistakes
- Assuming COBRA counts for Part B SEP purposes.
- Waiting the full 8 months and creating a coverage gap.
- Switching to Medicare Advantage without comparing Medigap when a guaranteed-issue opportunity is open.
- Skipping Part D and facing a permanent Part D late enrollment penalty.
A Practical Transition Plan
- Get the termination date of employer coverage in writing.
- Apply for Part B through Social Security (CMS-40B + CMS-L564).
- Decide between Original Medicare + Medigap + Part D or Medicare Advantage.
- Line up the new coverage to start the month after employer coverage ends.
- Cancel any unused COBRA offer.
Frequently Asked Questions
I am still working past 65. Should I enroll in Part B?
It depends on employer size and coordination. Employer with 20+ employees → often safe to delay. Under 20 → Medicare is usually primary.
Does this SEP apply if my spouse retires?
Yes. Losing spousal employer coverage also triggers the SEP.
What if I missed the 8-month window?
You may need to wait for the General Enrollment Period (January 1 – March 31), with a delayed start date and possible lifelong penalties.
How Summit Benefits Group Can Help
We coordinate the Part B enrollment timing, compare Medigap vs Medicare Advantage options, and help you avoid the penalty and coverage-gap traps.
Losing employer coverage soon?
Call (606) 249-6880 or request a Medicare transition review.