Enrollment
SEP for Losing Employer Coverage
Quick answer
Losing employer or union group health coverage triggers a Special Enrollment Period to enroll in Part B and to join Part D or a Medicare Advantage plan — typically 8 months for Part B and 63 days for Part D.
Plain-English definition
This SEP prevents the Late Enrollment Penalty for people who kept working past 65.
Why it matters
Missing this window causes a permanent premium penalty.
A simple example
You retire at 67. Your SEP window opens the month after your employer coverage ends.
Common mistakes & misconceptions
Related terms
Special Enrollment Period (SEP)
A Special Enrollment Period (SEP) is a window outside the standard windows when you can join, switch, or drop a plan. SEPs are triggered by qualifying life events like moving, losing employer coverage, or becoming eligible for Medicaid.
Employer Coverage
Employer coverage is a group health plan from your (or your spouse's) current job. If the employer has 20+ employees, you can usually delay Part B without penalty while you're still working.
Creditable Coverage
Creditable coverage is drug coverage — usually from an employer, union, VA, or TRICARE — that Medicare considers at least as good as Part D. Having it lets you delay Part D without a penalty.
COBRA
COBRA lets you temporarily continue employer coverage after leaving a job. COBRA is not considered active employer coverage for Medicare, so it does not delay your Part B enrollment window.
Frequently asked questions
Does COBRA extend this SEP?+
No — the clock starts when your active employer coverage ends.
Sources & references
📚 Where this information comes from
- Medicare.gov — official U.S. government site for people with Medicare ↗Primary source for benefits, enrollment periods, and plan comparison.
- CMS.gov — Centers for Medicare & Medicaid Services ↗Federal rulemaking, program updates, and official guidance.
- Social Security Administration — Medicare enrollment & premiums ↗Enrollment, premium withholding, and IRMAA determinations.
When you're ready, compare plans on your own terms
See Medicare Advantage plans from the insurance companies we represent, or walk the course with a licensed agent whenever you'd like a second set of eyes.
We help compare Medicare Advantage plans from the insurance companies we represent, and we don't offer every plan available in your area.
Medicare Caddies is an independent insurance agency. We are not affiliated with, endorsed by, or connected to the U.S. government, the federal Medicare program, or the Centers for Medicare & Medicaid Services (CMS). We help compare Medicare Advantage plans from the insurance companies we represent, and we don't offer every plan available in your area.