Most Americans can enroll in Medicare Parts A and B at age 65, regardless of whether they're still working or not. However, many workers with employer health benefits may not need to. Here's a quick guide to determine if you'll need to sign up for Medicare at 65, or if your other health insurance is sufficient until you retire.
The short answer
If you qualify based on your, or your spouse's, work history, you can sign up for Medicare when you turn 65, regardless of whether or not you've retired. (Note: If you aren't sure if you qualify, check your latest Social Security statement. It can tell you if you've earned enough "credits.")
In fact, if you've already signed up for Social Security benefits, you'll be automatically enrolled in Medicare Parts A and B starting in the month of your 65th birthday. If you haven't, you'll need to apply for Medicare, which you can do on the Social Security Administration's website in just a few minutes.
Do you need to enroll in Medicare if you're not retired?
Every American worker who qualifies based on their work record can enroll in Medicare when they turn 65, regardless of whether they're working or not. A more specific answer is that many non-retired 65 year olds need to enroll in Medicare, while it's fine for others to wait.
First, every 65 year old should at least enroll in Medicare Part A (hospital insurance), provided they qualify for it with no premium (most people do). It doesn't cost anything, so it doesn't make much sense not to sign up.
On the other hand, Medicare Part B (medical insurance) comes with a monthly premium, so for many people, it doesn't make sense to sign up for it if you don't need it. If you're automatically enrolled, but don't need Part B just yet, there are instructions on the Medicare card you'll receive that you can follow to cancel it. If you don't yet receive Social Security and need to sign up, the application will ask if you want Part B, or just Part A.
Here's the rule. In a nutshell, if Medicare will be your primary insurance, you need to sign up at 65, even if you're still working. If Medicare would be a secondary payer to your current insurance, you can wait. But how do you know?
If you have group coverage through your employer, or your spouse's employer, and the employer has more than 20 employees, you don't need to sign up for Medicare Part B at age 65. This meets the IRS definition of group coverage, and your insurance will remain your primary payer, even if you're older than 65. Once you leave employment, or lose the group coverage, you'll have an eight-month special-enrollment period during which you can sign up for Part B.
On the other hand, if you don't have group coverage, have coverage but your company has fewer than 20 employees, are covered through Marketplace health insurance, COBRA, or TRICARE (unless you're still active duty), you'll need to sign up for Medicare Parts A and B during your initial enrollment period, which is the seven-month period beginning three months before the month of your 65th birthday.
Make sure you know the right move for you
Unless you qualify for a special-enrollment period due to your group health coverage, be sure to sign up for Medicare during your initial-enrollment period. Failure to enroll in Medicare when you're first eligible can result in permanently higher Part B premiums, so be sure that you don't have to sign up, and check with your employer's benefits administrator if you aren't sure.
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