Questions & answers · Health insurance
I'm turning 65 but still working with job-based health insurance. Do I need to sign up for Medicare Part B now?
Health insuranceBuying a policyChecked Nov 5, 2026
From K.Actuary, founded by Sangmin Kwon, ASA · sources checked 2026-11-05 · Source: Medicare.gov · When can I sign up for Medicare? · answer «Sign up: Within 8 months after you or your spouse stop working» View original ↗
In short
- If you have job insurance from current work, you may be able to wait on Part B.
- When the job or the insurance ends, you have 8 months to sign up.
- COBRA does not extend that 8 months.
What this means
Medicare.gov says many people still working can wait to sign up for Part B. You then sign up within 8 months after you or your spouse stop working [1]. Part A is free for most people, so you may want it at 65 anyway [1]. The 8 months start when you stop working, even if you choose COBRA. If you lose the job insurance before you stop working, you also have 8 months [1]. If you miss the 8 months, you may have a gap and a monthly penalty for as long as you have Part B [1].
Who pays first matters. If you are 65+ and covered by a group plan from current work at an employer with at least 20 employees, Medicare pays second [2]. With a smaller employer, Medicare usually pays first, so waiting on Part B can leave a big gap. Ask your employer which rule applies before you wait. If you have COBRA and Medicare because you are 65+, Medicare pays first [3].
To use the 8 months, you need a form that shows you had job insurance while working [1].
Your next step
Ask your employer's benefits office how many employees the company has and whether the plan pays first or second after 65. Mark the date you will stop working.
Deadline: sign up for Part B within 8 months after you or your spouse stop working (or lose the job insurance).
Check it yourself
Use "When can I sign up for Medicare?" and "Who pays first?" on Medicare.gov. The amount of the Part B penalty for your case — "Don't know yet"; it depends on how long you went without coverage.
Where this comes from (3)
[1] Medicare.gov · When can I sign up for Medicare? · answer «Sign up: Within 8 months after you or your spouse stop working» · checked 2026-11-05
Your answer: Sign up: Within 8 months after you or your spouse stop working Most people don’t have to pay a premium for … So, you may want to sign up for Part A when you turn 65, even if you or your spouse are still working. … , you’ll have to wait to sign up and go months without coverage. You might also pay a monthly penalty for as long as you have Part B. … Your 8-month Special Enrollment Period to sign up for Par…
[2] eCFR · 42 CFR 411.172 · § 411.172(a)(3)(i) · checked 2026-11-05
Medicare Part A and Part B benefits are secondary to benefits payable by a GHP for services furnished during any month in which the individual— … Is aged; … Is covered under a GHP of an employer that has at least 20 employees (including a multi-employer plan in which at least one of the participating employers meets that condition), and coverage under the plan is by virtue of the individual's current employment statu…
[3] Medicare.gov · Who pays first? · answer text · checked 2026-11-05
Your answer: If you have Medicare because you’re 65 or older, Medicare pays first. If you have COBRA and you’re eligible for Medicare: COBRA may only pay a small portion of your medical costs You may have to pay most of the costs yourself.
How we found this
We matched your question to 3 official sources, quoted the exact lines, and re-checked each quote against its source on 2026-11-05.
What we don’t know yet
Your own plan or notice may say something different. If your letter cites another rule, send it and we will look again.
Every answer is checked against the official rule it quotes.
Information only — not legal advice. Your plan, insurer or agency decides.
This answer quotes the official sources listed above, with the date we checked them. Your own policy, notice and state rules control. We are not your lawyer or your insurer. We don’t file, argue or negotiate claims for you — you send any letter or form yourself.
Related answers
- How do I get out of Medicare Advantage and go back to Original Medicare, and can I still buy a Medigap plan?
- I'm turning 65 and have a Marketplace plan. What happens to it when Medicare starts?
- How does a Medicaid spend down work if my income is too high?
- My employer offers health insurance. Can I still get a Marketplace premium tax credit in 2026?
Answer id PQ1102. Spotted an error? Tell us.