Who can delay Medicare Part B enrollment beyond age 65 without getting hit with late penalties?

| Many people these days have health coverage beyond age 65 from their own or their spouses’ employers. In most cases, they can delay Part B enrollment and avoid its premiums until the employment ends, without incurring late penalties. A much rarer situation for postponing Part B enrollment without penalty occurs when a person who is not entitled to premium-free Part A returns to the United States after living abroad. 

If you have health coverage from active employment

After turning 65, you can delay enrolling in Medicare Part B (and avoid paying its premiums) for as long as you are covered under a group health plan provided by an employer for which you or your spouse actively works. (Note that “active” is the key word here. Retiree benefits or COBRA coverage from a former employer do not count as active employment.)

When the employment or health care coverage ends (whichever occurs first) — no matter how old you are — you are entitled to a special enrollment period (SEP) of up to eight months to enroll in Part B without getting late penalties.  During this SEP you can also sign up for Part A benefits (if you haven’t already done so) and for Part D prescription drug coverage. 

This rule also applies if you live outside the United States and you or your spouse is working, and you have health coverage provided by an employer or by the public health service of the country in which you live. 

However, the rule does not apply in certain situations: 

• If the company or organization that provides your health coverage has fewer than 20 employees, you may be required to sign up for Medicare Part B at age 65. That decision would be the employer’s. In this situation, you need to find out whether you must sign up for Part B. If you’re told you don't need to, get that decision in writing. 
• If you live in an unmarried domestic partnership and receive health insurance from your partner’s employer, you are not entitled to a special enrollment period when the employment ends. To avoid late penalties, you should sign up for Medicare at age 65. 
• If you are entitled to TRICARE but are no longer on active duty with the military — or if you are covered under your spouse’s military coverage — you must sign up for Medicare just before you turn 65 in order to continue to receive benefits under the TRICARE For Life program, which provides wraparound supplemental coverage to Medicare.

For more information, see the AARP article “Medicare When Working Beyond 65.”