Do I need Medicare Part B if I am still working at 65?

It depends on your employer's size. With 20 or more employees, you can usually delay Part B with no penalty. With fewer than 20, you must enroll at 65 because Medicare becomes your primary insurance.

Does COBRA let me delay Medicare Part B?

No. COBRA does not count as active employer coverage for delaying Part B. If you are 65 or older on COBRA, enroll in Parts A and B. Otherwise you risk late penalties and coverage gaps.

How long is the special enrollment period after my job ends?

You get 8 months after your employment or group coverage ends, whichever comes first. Enroll during that window to avoid the Part B late penalty.

What if my spouse's employer covers me?

The same rules apply. If your spouse is actively working for an employer with 20 or more employees, you can delay Part B under their group coverage. When it ends, your 8-month special enrollment period begins.

Should I enroll in Part A while I delay Part B?

Premium-free Part A costs nothing, so many people take it. But enrolling in any part of Medicare ends your HSA contribution eligibility. If you have an HSA, weigh that before signing up.

What happens if I miss the 8-month special enrollment period?

You wait for the General Enrollment Period, January 1 to March 31, with coverage starting July 1. The Part B late penalty may apply for the months you delayed without creditable coverage.

Guide · Updated October 8, 2026

Do I need Part B if I have employer insurance at 65?

Still working with good health coverage? You may be able to skip Part B for now. One number decides it: how many people your employer has.

(919) 408-6671 Get free help with the timing

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Christian Brinkley, licensed insurance agent in Greensboro, North Carolina — Christian BrinkleyNC Life & Health · Greensboro, NC

In short

Part B covers doctor visits and outpatient care, and it has a monthly premium ($202.90 in 2026). If your employer has 20 or more employees, you can delay Part B while you keep working, with no late penalty. Below 20 employees, Medicare becomes primary at 65 and you must enroll.

The 20-employee rule

Part B enrollment rules by employer size
Employer size	What to do at 65
20 or more employees	You can delay Part B with no penalty while you have active group coverage. Your employer plan stays primary. Enroll later through a special enrollment period.
Fewer than 20 employees	Enroll in Parts A and B at 65. Medicare becomes your primary insurance. Your employer plan pays second. Skipping Part B can leave bills unpaid.

Federal law also protects you at work. Employers with 20 or more workers must offer you the same health benefits at 65 that younger workers get. They cannot push you onto Medicare to save money.

The 8-month special enrollment period

When your employment ends, or your group coverage ends, an 8-month special enrollment period begins. During it you can sign up for Part B with no late penalty. The clock starts at whichever happens first: the job ending or the coverage ending. Do not let this window pass. After it closes, you wait for the General Enrollment Period and the penalty can apply.

The COBRA trap

COBRA lets you keep your old employer plan after you leave the job, but it does not count as active employer coverage. If you are 65 or older and on COBRA, you still need Parts A and B. People who treat COBRA as a reason to delay Part B end up with penalties and gaps. Retiree health coverage from a former employer has the same problem.

The HSA wrinkle

Enrolling in premium-free Part A sounds free, and the premium is. But any Medicare enrollment ends your HSA contribution eligibility. If you fund an HSA through work, delaying Part A along with Part B keeps the HSA alive. Here are the full HSA and Medicare rules.

Turning 65 soon? Here is the full turning-65 walkthrough. Leaving a job changes more than health coverage: here is how special enrollment periods work.

Medicare help in your community

Common questions

Do I need Medicare Part B if I am still working at 65?: It depends on your employer's size. With 20 or more employees, you can usually delay Part B with no penalty. With fewer than 20, you must enroll at 65 because Medicare becomes your primary insurance.
Does COBRA let me delay Medicare Part B?: No. COBRA does not count as active employer coverage for delaying Part B. If you are 65 or older on COBRA, enroll in Parts A and B. Otherwise you risk late penalties and coverage gaps.
How long is the special enrollment period after my job ends?: You get 8 months after your employment or group coverage ends, whichever comes first. Enroll during that window to avoid the Part B late penalty.
What if my spouse's employer covers me?: The same rules apply. If your spouse is actively working for an employer with 20 or more employees, you can delay Part B under their group coverage. When it ends, your 8-month special enrollment period begins.
Should I enroll in Part A while I delay Part B?: Premium-free Part A costs nothing, so many people take it. But enrolling in any part of Medicare ends your HSA contribution eligibility. If you have an HSA, weigh that before signing up.
What happens if I miss the 8-month special enrollment period?: You wait for the General Enrollment Period, January 1 to March 31, with coverage starting July 1. The Part B late penalty may apply for the months you delayed without creditable coverage.

Working past 65 and unsure what to enroll in? Call or text Christian Brinkley in Greensboro, NC at (919) 408-6671. The review is free, with no obligation.

Christian BrinkleyNC Life & Health · Greensboro, NC

Time your Medicare start around your work

Tell me about your employer coverage and your retirement date. We will map the enrollment steps so you skip the penalties. Call or text (919) 408-6671.

(919) 408-6671 Get free help with the timing

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