It depends on who pays first
| Your coverage at 65 | Who pays first | Do you need Part B now? |
|---|---|---|
| Group plan from your or your spouse's current job, 20 or more employees | The group plan | Usually no; you can delay without a penalty |
| Group plan from current work, fewer than 20 employees | Medicare | Usually yes; check with the plan |
| COBRA, retiree coverage or an individual plan | Medicare | Yes; sign up when first eligible |
If you're under 65 and have Medicare because of a disability, the threshold is 100 employees instead of 20. Ask your employer's benefits office how its plan works with Medicare before you decide.
Signing up when work coverage ends
- Watch the clock. You have eight months after your job or your group coverage ends, whichever comes first, to sign up for Part B without a penalty.
- Get the forms. Fill out form CMS-40B and have your employer complete form CMS-L564 to show your group coverage.
- Submit to Social Security. Apply online at ssa.gov, or call 1-800-772-1213 (TTY 1-800-325-0778).
- Add drug coverage. If you're leaving a group plan's drug coverage, you have two full months after it ends to join a Part D or Medicare Advantage plan.
- Consider Medigap. Your six-month Medigap open enrollment period starts the month your Part B starts.
Miss the window and you may wait for the General Enrollment Period (January 1 to March 31) and owe a Part B penalty of 10% for each full 12 months you went without it. Try the penalty calculator.
Oklahoma situations to check
- State, school and local government workers. If you work for an employer covered by HealthChoice through EGID (part of OHCA), or plan to retire with OTRS, ask how your coverage changes at 65 and at retirement. See state and teacher retirees and Medicare.
- Military retirees at Tinker, Fort Sill, Vance or Altus. TRICARE For Life generally requires Part B. See veterans, TRICARE and military retirees.
- Tribal health coverage. If you use IHS or a tribal health system, ask your benefits coordinator how Medicare fits. See tribal health and Medicare.
Get help
When you're ready to leave work coverage, a licensed insurance agent who works with Benefits Life can compare Medigap, Part D and Medicare Advantage plans from the companies they work with, at no cost to you. You can request a call from a licensed insurance agent. For more, see working past 65 and Medicare enrollment periods.
Related questions
How do I sign up for Medicare?
Online, by phone or in person.
When should I sign up at 65?
Your seven-month window.
What is IRMAA?
Why a high income raises your premium.
Sources
- Medicare.gov — Working past 65
- Medicare.gov — Which insurance pays first
- Social Security — Apply for Part B during a special enrollment period
- Medicare.gov — Avoid late enrollment penalties
- TRICARE — TRICARE For Life
More questions in this guide
- How do I sign up for Medicare in Oklahoma?
- What are the Medicare deadlines in Oklahoma for 2027?
- What happens to my Medicare plan if I move to Oklahoma?
- When should I sign up for Medicare if I'm turning 65 in Oklahoma?
Part of the guide: Medicare enrollment periods in Oklahoma · All questions
Frequently asked questions
Should I still sign up for Part A at 65?
If you qualify for premium-free Part A, many people take it at 65. But if you contribute to a health savings account (HSA), Medicare.gov advises you and your employer to stop HSA contributions six months before you apply for Medicare or Social Security, to avoid a tax penalty.
Does COBRA count as coverage from work?
No. COBRA doesn't extend your Medicare sign-up window. Your eight-month special enrollment period starts when your job or the job-based coverage ends, even if you choose COBRA, so sign up for Part B then.
What forms do I need to sign up for Part B later?
Form CMS-40B, the Part B application, and form CMS-L564, which your employer fills out to show you had group coverage based on current work. You can submit them online, by fax or mail, or at a Social Security office.
Medicare in your Oklahoma county
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