This article was updated on April 9, 2018, and originally published on July 16, 2017.
The standard eligibility age for Medicare in the United States is 65. However, many people don't know if they need to sign up for Medicare if they already have other health insurance coverage, such as through a job, a spouse's employer, from their former employer, or through COBRA. Here's a quick guide that can help you determine if you need to sign up for Medicare when you turn 65 or if you can wait longer without paying a penalty.
How Medicare works with your other insurance
When you have more than one insurance provider, there are certain rules that determine who pays what it owes first and who pays based on the remaining balance. For seniors who don't have other insurance, Medicare is obviously the primary payer. However, when you have other insurance, it's a little more complicated.
Depending on the type of insurance you have (group coverage, retiree coverage, COBRA, marketplace coverage, etc.), Medicare can either be the primary or the secondary payer. If Medicare would be a secondary payer to your current insurance, you can delay signing up for Medicare Part B. If your current insurance would become a secondary payer to Medicare, you should sign up during your initial enrollment period, which is the seven-month period that begins three months prior to the month you'll turn 65.
It's also worth noting that although I'm specifically mentioning Medicare Part B, which is medical insurance, this applies to Part A (hospital insurance) as well. However, Medicare Part A is free to the vast majority of Americans, so it's probably worth signing up for Part A whether you're required to or not. On the other hand, Medicare Part B has a monthly premium you'll have to pay ($134 per month for most new beneficiaries in 2018), which is why it can make sense to delay signing up if it's not going to be your primary insurance.
Who can delay signing up for Medicare?
So, whose insurance remains the primary payer? In a nutshell, if you have coverage through your or your spouse's current employment, and the employer has 20 or more employees, your insurance plan remains the primary payer.
If you aren't sure if your employer meets the "group health coverage" criteria, ask your employer's benefits manager.
If you do qualify, you can delay signing up for Medicare for as long as you (or your spouse) are still working. Once the employment or your employer-based health coverage ends, you'll have eight months to sign up for Medicare Part B without paying a penalty, which is a permanently higher premium.
It's also important to note that regardless of whether you're still working or not, if you've already signed up for Social Security benefits, you'll be automatically enrolled in Medicare Parts A and B when you turn 65. If you don't want to keep Part B, you'll need to cancel it (instructions are on the Medicare card you'll receive).
Who should sign up at 65, even if they have other insurance?
This leaves a fairly long list of other types of insurance that become secondary payers to Medicare. Therefore, if you're turning 65 and any of these situations apply to you, you should sign up for Medicare during your initial enrollment period.
- You have group coverage through your or your spouse's employer, but the employer has fewer than 20 workers.
- You have retiree coverage, either through your former employer or your spouse's former employer.
- You have group coverage through COBRA.
- You have TRICARE, the healthcare program for military service members, retirees, and their families. Retired service members must get Medicare Part B when eligible in order to keep their TRICARE coverage. (Note: If you're still on active duty, you don't have to enroll in Medicare until after you retire.)
- You have veterans' benefits.
- You have coverage through the healthcare marketplace or have other private insurance. Once your Medicare coverage begins, you'll no longer get any reduced premium or tax credit for marketplace coverage, and you should drop this coverage as you'll no longer need it (unless you're not eligible for premium-free Part A, which is not common).
If one of these situations applies to you and you don't sign up for Medicare Part B during your initial enrollment period, you could face permanently higher premiums when you do.