If you’re already receiving Social Security retirement benefits, you’ll be enrolled automatically in Part A at the beginning of the month you turn 65 or, if your birthday is on the first day of a month, during the previous month. You can’t delay Part A if you’re already getting Social Security unless you decide to stop your monthly checks and repay what you’ve already received.
Unless you decline, you’ll also be enrolled automatically in Part B, except in Puerto Rico, where everyone has to take steps to sign up for Part B.
Be aware: If you and your younger spouse both receive Social Security retirement benefits, your spouse cannot enroll in Medicare when you do unless your spouse has received Social Security Disability Insurance payments for 24 months or otherwise qualifies for Medicare early, such as having end-stage kidney disease or amyotrophic lateral sclerosis, better known as Lou Gehrig’s disease. Medicare is not a family plan, so your spouse will have to maintain the coverage you have now or look for an alternative while you explore your Medicare options.
If you’re not already receiving Social Security, in many instances you should sign up for Medicare Part A during your initial enrollment period, the seven months that start three months before the month in which you turn 65 and end three months after your birth month. If you get health care from the following places, you might have less coverage or different costs at age 65 and older than before you became eligible for Medicare:
- The Affordable Care Act’s health insurance marketplace
- COBRA from a former employer
- A Medicaid program from a state, territory or the District of Columbia
- A retiree health plan from a previous job or union
- Tricare military health coverage
- U.S. Department of Veterans Affairs health benefits
If you have health insurance through your employer, you still should sign up for Part A during your initial enrollment period. It’s even more important if you work for a company that has fewer than 20 employees, because Medicare will pay a claim before your company’s insurance. If you don't sign up for Part A, you could have a gap in coverage when your plan at work becomes secondary.
If you or your spouse have worked for 10 years and have been paying Medicare taxes during that time, Part A is free, so it’s often a good idea to enroll when you become eligible.
However, some people who work for a large employer choose to delay signing up for Part A and Part B so they can continue to contribute to a health savings account (HSA). HSAs are tax-advantaged savings accounts available to people who have high-deductible health plans.
Employers sometimes contribute to these plans in addition to employees. While the money has to be used for health care expenses, it does not have to be used in the year it is deposited. After you enroll in Medicare, an HSA can still be used for eligible expenses, but you can no longer make new contributions to the HSA.